DO THE TON

Turn your Brain Off and Shoot the Shit => The Collections => Bobbers / Chops / Specials => Topic started by: hallin222 on Jun 09, 2012, 18:52:00

Title: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Jun 09, 2012, 18:52:00
OK, so after much harrassment from others, I finally decided to start a build thread for the project bike I've had for about a year now.  Progress was delayed for much of 2011 due to shoulder surgery, but I'm back now, and the KZ is coming along a little better now.

Back story: a year or so ago, I helped a friend transform his 1976 CB750K from stocker to rocker (see pics below) and had so much fun, I wanted to work on a bike that I actually got to keep when I was done. 

(http://farm9.staticflickr.com/8013/7355582318_396280361d_b.jpg)

(http://farm8.staticflickr.com/7089/7355582536_ca0319b71c_b.jpg)

(http://farm8.staticflickr.com/7232/7170370111_9d685fce1d_b.jpg)

For MY bike, I kind of wanted a vertical twin, but needed to build a bike on a very tight budget, so Triumphs and Nortons were not an option.  Even XS650's seem to go for big money in the Austin area, so those were out as well.  I'm also a bigger guy (6'3"), so smaller twins (CB350, 400, etc) would just look silly with me aboard, so my search began for a big Kawasaki twin.  I fell in love with the Wrenchmonkees stuff and saw what was possible with them, so I scored a junker for a few hundred bucks.  Nasty, huh?

(http://farm9.staticflickr.com/8142/7290570210_773dd4507f_c.jpg)

(http://farm8.staticflickr.com/7077/7290570946_188352f3b0_c.jpg)

Ugh.  This is how I received the rest of it.

(http://farm8.staticflickr.com/7085/7290564324_d20c2eaf7d_c.jpg)

I won't bore you with most of the teardown photos, as you're all familiar with the procedure, and they were for my own reference anyway.  It didn't take long for it to end up like this.  Tail cut, de-tabbed, and passenger peg / exhaust hanger brackets hacked off.

(http://farm8.staticflickr.com/7231/7290563058_452dc6869b_c.jpg)

More to come......

Title: Re: Project: "HonkyKong" 1979 KZ750B Twin (brat-tracker-thingy)
Post by: hallin222 on Jun 09, 2012, 19:36:04
Knowing I had lots of parts to strip and re-paint on this project, I invested in a cheap Harbor Frieght sandblast cabinet and went to town.  I few other friends have build projects going on too, so I knew it'd get used enough to justify the expense.  Lucky, wifey is pretty accepting of tool purchases, seeing them as long-term moeny savers, allowing me to do more myself, rather than paying others to do it for me.

Just some of the parts that got sanded and/or blasted and re-painted:

(http://farm8.staticflickr.com/7074/7290565598_fab12fd732_c.jpg)

This engine is actually from another parts bike I picked up for free, if I remember correctly.  It's from a 1980 KZ750G, and looked to be in better shape than the 'B' model's gas burner.  I had it running on one cylinde prior to cleaning the carbs and acquiring a new coil, so I'm confident it will serve me well.

(http://farm8.staticflickr.com/7090/7290564420_82c6e76707_c.jpg)

(http://farm9.staticflickr.com/8149/7290565218_4249dc1294_c.jpg)
Title: Re: Project: "HonkyKong" 1979 KZ750B Twin (brat-tracker-thingy)
Post by: hallin222 on Jun 10, 2012, 01:11:40
Here are some bad cell phone pics of my first idea of seatpan and rear hoop.  It was taken from the rear of a 1980 KZ750 (4 cylinder) that a friend of mine is hardtailing.  Luckily, the width was the same as my frame, 'cause he had a hell of  time trying to bend two identical 90 deg elbows with a cheap hydraulic pipe bender.  A 180 'U' was going to be impossible with our tools, and this fit pretty well, so I took the cheap, easy way out.   The low res pic is probably a good thing, so you can't see my horrible welds.  No worries, though.  I smacked it with a mallet several times to test its strength, and I'm able to lift the entire rear of the bike (with engine, forks, swingarm, and wheels installed) from it without trouble.

(http://farm8.staticflickr.com/7215/7290566386_5765b880d4_z.jpg)

Yes, this is ugly, but my borrowed MIG had a less than predictable feed, and this was my first real attempt using it.  Since its not really a load bearing section like the neck, engine cradle, or triangulated rear section, I'm not too worried about it.

(http://farm9.staticflickr.com/8002/7290565904_74e0853aa8_z.jpg)
Eventually, that section looked like this, after a small filler section was added from a wedge cut from a junk handlebar, then ground, bondo'd, and sanded smooth.

(http://farm8.staticflickr.com/7101/7290566276_6b9c365c76_z.jpg)

WARNING: Firestone Alert!  Haters gonna hate.  I still dig 'em.

(http://farm9.staticflickr.com/8007/7290565716_dc5f37f377_c.jpg)

My first loose roller mockup.  The new bearings (wheels & steering neck) have yet to be installed in this pic, but it was more to get me motivated to keep working once I saw what looked remotely like a motorcycle again.  The bars are some aluminum Renthal MX bars I bought as a pile of parts from a guy, who also provided that front Firestone.

(http://farm8.staticflickr.com/7215/7290566516_d01718cdae_c.jpg)

Title: Re: Project: "HonkyKong" 1979 KZ750B Twin (brat-tracker-thingy)
Post by: hallin222 on Jun 10, 2012, 09:41:53
The next step was to paint the frame, install new bearings, and get the engine re-installed.  Big thanks to my buddy, John, for helping with that step.  Lifting a big twin into a freshly painted frame is not something I would have wanted to do with only two hands.

It's starting to look like something now.  Those pipes are actually off the same 1980 KZ750G that I lifted the engine from.  I wanted the disc brake rear end of the "B" model vs the drum of the "G" model, so the swap of everything was necessary.  I could have just swapped the rear wheels and swingarms, but the '79 "B" frame also has that rear master cylinder mount, seen in the front of the main triangle, that I didn't want to have to cut and re-weld, so I kept the '79 frame.

I'm not sure that the 18" cast rear wheel was stock on this bike, and it may have been transplanted from a KZ1000 or something, sometime earlier in this bike's life, but I'm not sure.  I'm still having slight rear wheel alignment issues, so it someone can explain (or provide measurements for the) stack up of spacers on that axel, it would be greatly appreciated.

(http://farm9.staticflickr.com/8020/7290566652_3472b9c000_c.jpg)

It's not really visible here, but currently my wheel is sitting a little left of center, which I had to do to get the rotor bolts to stop rubbing the inside of the caliper mount.  I still need to figure that out.  My parts diagrams don't exactly represent the collection of parts and spacers that my bike has, which led me to believe that rear wheel was not stock.

(http://farm9.staticflickr.com/8165/7290567782_6be4fce5e9_c.jpg)

Also notice my paper mockup of my proposed underseat electrical tray.  I took some manual measurements, modeled it in SoldWorks, then printed a 1:1 flat pattern to cut out and fold up before trying it with sheet aluminum.

(http://farm9.staticflickr.com/8165/7290566770_6041452625_c.jpg)
Title: Re: Project: "HonkyKong" 1979 KZ750B Twin (brat-tracker-thingy)
Post by: hallin222 on Jun 10, 2012, 15:53:43
Here are a few shots that are chronologically earlier than those posted above (notice no carbs or pipes installed yet), but are a little clearer and provide more info about the overall stance of the bike.  The 2nd image, in particular, makes the entire bike look taller than I'd like, but without the full weight load (of both the missing parts and rider), and the lack of pipe running under the frame to fill that frame-to-ground space, I think it's just an illusion.  The addition of more parts and pipes in future images make the bike look lower than that, which I prefer.

(http://farm8.staticflickr.com/7235/7173393635_1b30f84a85_c.jpg)

(http://farm9.staticflickr.com/8141/7173393839_f0ee3d4c34_c.jpg)

This is why I can't ride small bikes.  With the frame cut, I'll be using 90% of what's left of the seating area.  I assumed as much going into this, which is why the rear peg mounts were some of the first things to be cut from the frame.

(http://farm8.staticflickr.com/7075/7358622208_9859cb7fbd_c.jpg)

Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: sinbad85 on Jun 11, 2012, 09:34:45
sign me up!
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Jun 11, 2012, 23:32:13
sign me up!
Alright, sinbad, it appears we have a little Kawi 750 twin build-off brewing here.  :-) Unfortunatley, I'm way behind you, and starting with a much rougher doner, but I'll do my best with what I've got.  Stay tuned, and chime in with advice anytime.

Even pushing this bike around the yard, the forks feel WAY undersprung.  If anyone has a suggestion for this in the way of stiffer donor springs from another 36mm Kawi fork, please let me know.  At my weight, I'll want something stiffer, especially with the bike lowered a little, like it will likely be when completed.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Jun 12, 2012, 00:10:01
Exhaust chopping time.  While these 1980 KZ750 G pipes were in pretty decent condition, I just wasn't loving the long, stock look, and knew I didn't want a stock sounding bike when done, so I scored these Harley mufflers off a 1999 FXDX Super Glide Sport in trade for a 6-pack of Shiner.  They were even pre-cored of their restrictive factory baffle via a hole saw, and while still filled with the larger diameter, perimeter baffle, you can look right down through the 1-3/4" center of these.  I actually owned a '99 FXDX back in '99-'00, before buying the 2000 version of the same bike (which I still own today).

Stock Kawi pipes:
(http://farm9.staticflickr.com/8020/7290566652_3472b9c000_c.jpg)

Closer:
(http://farm9.staticflickr.com/8165/7290566770_6041452625_c.jpg)

H-D mufflers installed, after cutting the header pipes just ahead of the stock crossover tube.  I hope the removal of that crossover doesn't give me difficult tuning issues later, but I'll figure it out.
(http://farm8.staticflickr.com/7088/7290566944_c861e3d72b_c.jpg)

Other side:
(http://farm8.staticflickr.com/7095/7290567932_00ac309c8d_c.jpg)

Closer:
(http://farm8.staticflickr.com/7242/7290567052_e2e4d64615_c.jpg)

The fatter muffler section meant that the exhaust could now longer be run along or near the same vertical plane as the lower frame tube.  My first solution to this (starting on the  right side) was to rotate the header pipe outward, allowing the short, fat muffler clear the frame tube to the outside.  All was well, as it still cleared the kicker arm through its full movement, but this solution was not viable on the LEFT sie of the bike due to the kickstand bracket.

The new solution was to use the same header pipe rotation, but now to the INSIDE of the lower frame tube, placing both mufflers tightly under the bike slightly, for what I found to be actually a very cool look, although subtle.

Right:
(http://farm9.staticflickr.com/8161/7290567556_5472eb51ae_c.jpg)

(http://farm9.staticflickr.com/8001/7290567122_08ea427ae6_c.jpg)

Left:
(http://farm8.staticflickr.com/7215/7290567672_4c652185bc_c.jpg)

Rear:  I love this shot, and the narrowness this creates.
(http://farm8.staticflickr.com/7232/7290568414_c13815418f_c.jpg)

These were just clamped on loosely, requiring some High Life can shims to get a tight fit to the headers.  I still need to fabricate a sheetmetal bracket to support the rear of the mufflers via the H-D carriage bolt and slot mount, and some rubber-coated P-clamps that I'll be hanging from the horizontal frame tube just behind the oil pan.  I removed the stock centerstand brackets when hacking other bits of this frame last summer, so they're no longer available for use in that regard.

Area needing the custom bracket.  Note the tight clearance to the frame tube and oil pan.  The P-clamps are not shown, but you can see where they'll be going.  With some black paint on it, that bracket should mostly disappear from view, giving the mufflers a clean look, without excess clutter.
(http://farm9.staticflickr.com/8013/7290568264_af61621861_c.jpg)

I think this muffler solution also give the bike a little lower look by filling the empty space under the frame.  I'm happy with it, and for the cost of a 6-pack of beer, I couldn't be happier. 


 
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: sinbad85 on Jun 12, 2012, 03:46:00
exhaust looks good dude....

apparently removal of the link pipes slightly reduces torque...... i did it however and didnt notice much loss at all....
these kz's have stump pulling torque anyway.....

haha bring the build off on!!!
i dont plan on having mine finished within six months though.....

good luck on the build dude! ill be watching......
and using yours for inspiration too!
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: tron97 on Jun 12, 2012, 03:58:54
Loving it so far. Im tunin in

Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Jun 13, 2012, 01:28:18
Custom fork brace pics below.  Note that I didn't create this from scratch.  The dual arch brace was acquired along with a bunch of other parts, many of which came off 70's era enduros, I think.  This was just too cool of a piece not to use, so I made that center rib from a chunk of 1/4" aluminum plate, that was then rolled (via the help of fresh_c) to the approximate radius of the tire.  I tapped the two mounting holes for metric fasteners for bike consistancy, then drilled it full of holes and sanded it smooth for asthetics.

However, the pre-existing fork mounting hole locations and side plate width didn't exaclty fit the KZ forks, so I cut up some side plat spacers (barely visible in pics) out of 1/4" aluminum plate on each side.  Also, with the 1/4" strip now mounted UNDER the arches (which I love the look of), the center rib grazed the tire slightly.  If that happened when stationary, It would cause a problem at speed, so I slotted those holes with a round file to allow the assembly to sit a little higher off the tire.  I hope there is enough clearance.

(http://farm8.staticflickr.com/7230/7367613300_5826da9e75_c.jpg)

(http://farm8.staticflickr.com/7071/7367613432_354897665d_c.jpg)

(http://farm9.staticflickr.com/8167/7367613404_72dce02255_c.jpg)

(http://farm8.staticflickr.com/7092/7367613366_ae4985c9b2_c.jpg)

It's a pretty close fit here.  Should I have any concerns about tire 'growth' at speed?  Also, ignore that ugly right fork leg.  It will get sanded down before this project is all done.
(http://farm8.staticflickr.com/7088/7182380671_ec8a61dd36_c.jpg)

Feedback is welcomed.  Keep it coming.  I have a few stylistic ideas for this bike, but am open to suggestions.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: sinbad85 on Jun 13, 2012, 07:59:47
wholly shit dude that is one AWESOME looking fork brace!!

just dont plan on going riding in the rain.....(although we never actually "plan" riding in the rain now do we?) haha

well done!
i was going to bend something up out of some 8mm or 10mm steel rod. but i dont think it will look anywhere near as good as that!
has certainly given me some ideas!

the only thing ide be concerned about is the clearance... at say 80mph or above the tyre is going to have a massive amount of centrifugal force on it thus trowing the tyre out.....
just hope it dont rub!!

Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Jun 13, 2012, 11:15:08
It's been brought to my attention via PM that this is not the world's stiffest design, as it's more of a fender mount, really, which I'm aware of.  It'll never behave like a true brace, and I'm ok with that, considering I was going to run no fender or bridge of any sort until I stumbled across this part.  Honestly, I just think it looks cool.  There is also the possibility of me raising it of the tire another 1/8" or so if absolutely needed, but there is no need of running it 1-3/4" off the tire as was suggested via PM.  No STOCK fender even sits anywhere near that high.

Perhaps I should have called it a "custom decorative fork treatment" or something more appropriate.  This was done 90% for asthetics, rather than performance.  I'm not looking for the fastest, best handling, best braking bike here, just a fun, cool looking cruiser that I'll be proud to have built myself.  If I were after all-out performace, I wouldn't have mounted up those Firestones, or chosen a heavy 30+ year old motorcycle as my foundation.

There is also concern (from others) regarding the lowered forks.  While I may lower it 'properly' via shorter, stiffer springs, the ride height viewed here isn't that low and has no frame or header clearance issues with the front tire.  I would like to stiffen the front end though, so if anyone knows of another model's springs that might fit my needs, please chime in. 

Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: JRK5892 on Jun 13, 2012, 14:31:31
really a good looking build so far
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: rays650cafe on Jun 14, 2012, 00:42:12
Seriously good stuff goin on here. I have concerns about your fork decoration being so close to the front tire. I don't know ya, and it wouldn't concern me as much if it were over the rear tire. But I have been over the handlebars at high speed. It sucks. I got lucky,me and my bike landed in the soft stuff. i just hope you reconsider the extra 1/8 inch before you "see" if you need it. Guessing those old school tires grow at speed. If it were the rear tire in question, I figure it would just flat spot at worse,add a little excitement to your ride. Thats the front, That could ruin a tire and a pair of underware. Just my .02 nice build,good riding.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Jun 14, 2012, 01:13:21
I'll consider it, but it doesn't appear to be any closer than what is seen here:

http://xlforum.net/vbportal/forums/showthread.php?t=1141559    ...but maybe that closeness is allowable with a radial tire.  (?)

My bike is far from being operational, so I have plenty of time to adjust it.  Notice no brakes, no wiring, and that tank is just a rusty, dented junker being used for visuals and general mock-up.

Next up will be some info on the battery tray and seat pan I'm working on.  I just haven't uploaded my photos to my hosting site yet. 
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: casper3043 on Jun 14, 2012, 03:45:58
love this thing mang! style is really close to mine. keep up the good work and keep us updated.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: warpedworm on Jun 14, 2012, 16:23:33
Nice build :)  I'm a big fan of the Kawi twins, although mine are much smaller.
I hope to build up a 750 someday.

Really like the looks of your bike.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Jun 16, 2012, 10:01:28
Here are a few shots of the electrical tray I made.  I first took a few measurements of that area of the frame, then modeled this sheet metal part in SolidWorks.  This allowed me to print the flat pattern of the part and test-fit it as a cut and folded paper sample (see previous images).  When the paper box seemed to fit about like I wanted it to, I went about cutting out the flat pattern out of 1/8" aluminum sheet.  This was overkill, and I could have used a much thinner material, like .070" or something, but this box will be extremely dent resistant over its lifetime.

The forming of the box was actually pretty difficult, given the manual brake (sheet metal bender) I had access to, and the complexity of multiple internal bends.  Again, since I have no ability to weld aluminum, I riveted the corners together.  I actually prefer this look to welds anyway.  DTT member, fresh_c helped me form and rivet this, as my bends weren't perfect and it took some C-clamps and muscle to get everything to line up before drilling and riveting. 

If I can find some images of my flat pattern, I'll post those up soon too.

(http://farm8.staticflickr.com/7224/7379204812_2d05be1571_c.jpg)

(http://farm8.staticflickr.com/7232/7379205004_b69bf67a09_c.jpg)

These mounting tabes were originally made quite oversized, but I waited until I held the box up under the bike frame to trace the tab arcs, and mark the holes, to ensure proper alignment, before finishing their trimming with a Dremel and hand files.  The bolts currently installed (up from the inside) are too long, but will be replaced with some with shorter thread shafts, to sit flush with, or below the top plate, as to not make contact with my custom seatpan.

(http://farm6.staticflickr.com/5456/7379204956_24995e0487_c.jpg)

First shot of seatpan.  This is .070" aluminum, if I remember correctly.  I gave it a slight kink down the centerline to give it a little rigidity before making the other two bends to fit the frame properly.  I'll get some better pics up soon.

(http://farm9.staticflickr.com/8025/7379205106_a308d2d2fd_c.jpg)

Now, because I'm a larger guy, and I may end up running 1" shorter shocks in the future (maybe not, we'll see) I wanted to check tire clearance through the full range of motion, so I removed the shocks, slid the rear axle as far as it could go forward in the axle plates, and lowered the bike on the jack until the tire made contact with something.

(http://farm9.staticflickr.com/8024/7379205170_31c580537f_c.jpg)

(http://farm9.staticflickr.com/8143/7379205140_72167a97a1_c.jpg)

Although it hits the rear of my electrical tray before touching my rear frame hoop and tail light / license plate mounting tab, it's unlikely that this will ever occur in practice.  If I move the axle back 1/2" in the axle plate (usually required to attain proper chain tension) the electrical tray clearance problem disappears, and the concern becomes the rear frame bar, at the 12:00 position over the tire.

(http://farm8.staticflickr.com/7214/7379205202_f53cafd96e_c.jpg)

My next step is to cut out the necessary area of the seatpan's rear section, and create two crecesnt / wedge shaped side peices and an arced inner fender to create a bump for tire clearance, much like old drag racers would 'tub' their rear wheel wells to make room for big, wide, tall slicks.  This will also be riveted together, with the heads of the rivets only being visible from under the bike, and maybe slightly from the rear, but unlikely once the tail light and licensce plate bracket are installed. 


Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: sinbad85 on Jun 16, 2012, 22:53:32
awesome seatpan dude!!!!
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Jun 17, 2012, 15:36:22
awesome seatpan dude!!!!

Thanks.  I was going to post some photos of my first attempt at the inner fender, but I can't find my camera today.

Does anyone know where I might find a set of exhaust collars for the 'G' headers I have?   I'm missing ONE of the four 180 degree arcs.  I need just the plain flat kind, not the stepped ones that the 'B' header flanges used.  I see sets on Ebay, but they're stupid expensive and I just need ONE, not a full set of four.

Like this: 
(http://i.ebayimg.com/06/!B3RsYPgB2k~$(KGrHqZ,!hYE)75Z81,zBMlmyDPwEQ~~_35.JPG)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Jun 20, 2012, 00:24:10
Excuse the horrible cell phone pic, but here's my plan for creating a rear tire 'tub'.  This is just a rough draft, it'll probably end up being about 1" wider than the max tire width, which should be overkill, since the widest part of the sidewall won't ever sit up that high, even under full compression.  Now I'll have plenty of vertical clearance as well, without worry of tire rub on that rear edge of the seatpan. 

(http://farm8.staticflickr.com/7087/7405164600_ee47b79291_z.jpg)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: zero on Jun 21, 2012, 17:29:54
great build so far!
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: fresh_c on Jul 04, 2012, 16:48:35
Need updates!
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Jul 07, 2012, 10:20:28
As requested, here are a few pics of the modified seat pan.  Big thanks to frash_c once again, for help with both the concept and implementation.  I think it came out well for a couple of amatures.  It looked prettier before we slathered it in silicone, but that side will all be covered with foam and vinyl at some point anyway.

I still needs to create a tab & slot mount for the front end, and no shown in these photos is the pressed in pemnut that will secure the rear, after I drill the frame tab to allow a mounting bolt to pass through it.  That fastener will likely be a wingbolt, knurlded head, or some other 'tool-less' one to allow removal of the seat, for access to the electrical tray should I ever need quick access on the side of the road somewhere.

(http://farm9.staticflickr.com/8281/7520147266_cebeab136a_b.jpg)

(http://farm8.staticflickr.com/7106/7520147144_6469ea2fdb_b.jpg)

(http://farm8.staticflickr.com/7130/7520147310_a7cf5452c0_b.jpg)

(http://farm8.staticflickr.com/7112/7520147088_af86101dac_b.jpg)

I'll be doing a little hand sanding / dremel-ing of the edges, to soften them, in case or tire contact, but the tub is about 3/4" wider than the widest point of the tire's sidewall, so I'm confident I won't have any serious issues.  This design won't allow me to have the seat foam as thin as I was hoping, as I'll still need some cushioning material placed on top of the tub, but I'll see how it all looks when I start layering it on.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: fresh_c on Jul 07, 2012, 15:22:17
That seat pan turned out pretty great.  Between the Firestones and the rivet heads, your bike is starting to a have nice post WWII hot rod style to it.  How about some fancy text on the tins to tie everything together?
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Jul 07, 2012, 15:45:35
How about some fancy text on the tins to tie everything together?
This graphic artist has volunteered to add some images to my tank, when it's ready for him.  I plan to strip it raw, then sand and clearcoat it, giving him a clean slate to work with.

Examples of his work can be seen here.  He's done work for local and international companies, including some of the T-shirts for Deus Ex Machina.

http://www.neighborhood-studio.com/

Some of his prints can be purchased here.  I recently bought the "Animals A-Z" print for some friends to hang in their new baby's room. 

http://store.neighborhood-studio.com/
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Jul 16, 2012, 00:44:12
I made up this little exhaust bracket over the weekend to support the rear of the system.  Nothing fancy, but it does the trick.  Sorry for the bad cell phone pics.  I couldn't find my camera.

This was just cut up with an angle grinder and a drill.  A bandsaw and belt sander would have provided a cleaner finished product, but I'm ok with it as-is, since it's mounted up under the frame. 

Those are just simple rubberized P-clamps hanging off the lower rear frame tube.

(http://farm9.staticflickr.com/8024/7580007486_3f9bea8a2c_z.jpg)

(http://farm9.staticflickr.com/8283/7580057574_64e709b1ec_z.jpg)

Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hitman46mod on Jul 16, 2012, 18:30:43
Nice looking bike so far! 8)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: diggerdanh on Jul 16, 2012, 23:02:37
Good idea on the exhaust bracket. I wondered how I would support the mufflers if I decided to cut off the rear portion of the frame with the passenger pegs. I think my mufflers sit a little higher but still something to file away for the future.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Jul 16, 2012, 23:35:30
Good idea on the exhaust bracket. I wondered how I would support the mufflers if I decided to cut off the rear portion of the frame with the passenger pegs. I think my mufflers sit a little higher but still something to file away for the future.
Yeah, this could easily be tweaked to accomodate higher-hanging pipes.  If you're doing any kind of wider-spaced, angled-up mufflers, a similar (but better-finished) P-clamp could be hung from the rear tiangle of the frame too.  Maybe some of the clamps used on Harleys for highway pegs, etc.

Something like these hinged ones, made by Kuryakyn: 
(http://cdn.cheapcycleparts.com/images/manual/production/product_images/199275/supersize/Kuryakyn_P-Clamps_4014_P-Clamp_-_39mm___41mm_-_Chrome.jpg) 

Or a 3-piece bolt-on style: 
(http://www.phatperformanceparts.com/photos/4405-0009.jpg)

I like your 2nd transformation of Project Grimey too.  Well done.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Sep 01, 2012, 15:33:36
Small update.  Got some lights mounted up.

This bracket still needs paint, but I wanted to test fit it first, in case I needed to re-bend it.

(http://farm9.staticflickr.com/8037/7907901746_0a0e30aa4b_c.jpg)

I'm not sure if I'll paint the rear one, of just leave it raw sheet aluminum.  I may box the sides of it to better hide the socket base and wire leads out the back.

(http://farm9.staticflickr.com/8178/7907901246_6bb82b9cc4_c.jpg)

(http://farm9.staticflickr.com/8454/7907900676_03afb55b9c_c.jpg)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: zlittell on Sep 02, 2012, 14:15:29
This build is looking fantastic!  I might be stealing a couple of your ideas for my build haha.  what did you paint that engine with and what did you paint the frame, wheels, small parts with.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Sep 03, 2012, 11:02:33
This build is looking fantastic!  I might be stealing a couple of your ideas for my build haha.  what did you paint that engine with and what did you paint the frame, wheels, small parts with.
Thanks.  The frame, wheels, and small parts were just shot with some generic primer, then some gloss black Rustoleum from Lowes, I think.  The engine was maybe the PJ1 VHT matte or satin black, whatever that high temp engine paint was at AutoZone.  I think I got the 2000F stuff, and hope it holds up.  I going off memory here, as I did it so long ago (it sat for the better part of a year, in peices, while I rehab'd from shoulder surgery in late 2011).  I may have described it on earlier pages if you want to scroll back.

Feel free to steal ideas.  Isn't that what sites like this are for?  I have an "inspiration" folder of photos on my PC full of images borrowed from here, and various bikes from around the world wide interwebbings.

I have been considering adding some color to this bike, since much of it is SO black so far.  I like some of the brown seats I've seen, but was considering adding some green to this old Kawi, while not actually using "Kawasaki green".  What does everyone this of a meaterial similar to this distressed green leather:

http://cdn.jaysonhome.com/media/catalog/product/cache/1/image/9df78eab33525d08d6e5fb8d27136e95/h/g/hg142060.jpg

...perhaps with a shape and diamond stitch pattern similar to this: 

http://www.facebook.com/photo.php?fbid=359999520743623&set=a.118016774941900.21775.117853428291568&type=1&theater
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: AJWatUC on Sep 03, 2012, 11:06:31
bike looks awesome nice job
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Sep 03, 2012, 11:30:41
More updates.  I got the $3 ebay horn (the stock one was huge, ugly, and would have been more difficult to reloate) mounted up and under the tank.  It won't be visible when the tank is on, as seen in the profile shot. The aluminum plate was made extra long, so I can cut a horizontal slot into it to accept the tongue I'll be attaching to the nose of my seatpan.

I also mounted the voltage regulator outside of my custom electrical box, as recommended by many DTT members, for better cooling.  It also frees up some very limited space within that box, which will house my mini battery, starter relay, fuse block, etc, as well as other necessary bits like my ignition switch, starter botton and horn button.

(http://farm9.staticflickr.com/8314/7921415712_a24fbe7125_c.jpg)

(http://farm9.staticflickr.com/8170/7921416714_a45c945fd7_c.jpg)

(http://farm9.staticflickr.com/8451/7921418174_e3e7f7857a_c.jpg)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Sep 03, 2012, 18:56:06
Playing around with some tank options.  Stock vs. 3.3 gallon Sportster peanut tank ('96-'03 era?), which would obviously require a little fabrication work to make it fit / sit properly.  I like stock.

(http://farm9.staticflickr.com/8448/7925002836_a6a6cdaf23_c.jpg)

(http://farm9.staticflickr.com/8041/7925001818_8c32752861_c.jpg)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: YogiBear on Sep 03, 2012, 18:59:40
definitely stock  ;)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: M.B Co on Sep 04, 2012, 13:56:38
Stock
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: JustinLonghorn on Sep 04, 2012, 14:05:04
Yep. Stock.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Sep 06, 2012, 16:00:38
So, no feedback on the idea of a seat with this kind of coloring?

(http://farm9.staticflickr.com/8302/7944997474_8dfbf19cae_z.jpg)

with this kind of stitching: 

(http://img.jpcycles.com/zoom/605-482_A.jpg)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: JustinLonghorn on Sep 06, 2012, 16:20:21
Do it!
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: canyoncarver on Sep 06, 2012, 19:01:04
sweet kawi.  subscribed
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: Finnigan on Sep 06, 2012, 20:10:17
If possible I'd go with the chair's coloring AND stitching...old fashioned style
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: zlittell on Sep 07, 2012, 20:59:07
that color with the diamond stitching would be sick.  i love that like grime green going on there
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: Bert Jan on Sep 07, 2012, 21:42:56
Really depends on your tank. Its the combo that makes or breaks it.. Green with those stiches is a -cant go wrong- i guess, but just my .02
Stock tank fo sho btw, those harley tanks are a waste of metal. (as are harleys :))
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Sep 08, 2012, 21:53:04
If anyone stumbles on a source for such a material, please send it my way.  I'm having difficulty finding 'outdoor rated' leather in the finish seen above.

Also, I actually own two H-Ds.  But I think both would likely get some level of approval in this crowd.  Not much chrome to be found on either.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: damarble on Sep 10, 2012, 13:08:31
Bike is turning out great. Yay for KZ twins! I can't say I approve of the tires tho.  ;D
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: tron97 on Sep 11, 2012, 15:54:22
Pics of the HD's!

Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Sep 12, 2012, 00:16:16
Pics of the HD's!

Here's my Sportster cafe build thread:  http://xlforum.net/vbportal/forums/showthread.php?t=594781

It pretty much looks like this now.  It's run a 12.9 at 102mph in the 1/4 before the cafe conversion, with a bad, heavy pilot aboard. 

(http://farm5.static.flickr.com/4017/4693957331_f89c515426_b.jpg)

I'd really like to put a proper tail on it, but since I'm not willing to cut the frame on this bike, my options are limited.  The best option is the Airtech Streamlining XLCS tail seen here:

(http://www.airtech-streamlining.com/vintage/images/seats/XLCS~1.JPG)

(http://www.airtech-streamlining.com/images/XLCSSPRINT.JPG)

A low-res, and out-of-date photo of my Dyna is here.  I've changed a few things since the pic was taken years ago, most notably a black 2-1 Thunderheader exhaust, and smoked turn signal lenses, but you get the idea.  I consider the Dyna basically 'done' except that I may remove the mirrors, put on slightly lower, narrower flat track riser bars, and a low profile, smoked tailight, but those are minor details.  I took this motor from 62rwhp to 110rwhp.  Those numbers on the tank are from when I used to ride it to the track for test & tune nights.  My best run was about a 12.3 @ 111mph (also with fat old me in the saddle) before the pipe swap and ignition upgrade. 

(http://www.clubchopper.com/photopost/data/500/1163FXDX_1.JPG)

Here's an MS Excel plotted graph of my various dyno runs, over a few years of engine modifications.  If you're an H-D guy who wants details of components of each stage, just let me know.  The only one that's NOT my actual bike is the green dotted line, but I put it in there as a comparision to what many H-D owner do as their first step.

(http://farm9.staticflickr.com/8439/7978473238_e9fba3992c_b.jpg)

I hope this satisfies the request.   ;)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: sinbad85 on Sep 12, 2012, 08:55:44
nothing but straight up respect from me.....(60 to 110 hp)
thats sick!
i will get a hd one day...... i want to get a buell xb12 and chuck it all in a hardtail frame with buell front end and wheels etc...
 you have 2!!!

i still reckon your kz looks better though........
love the tracker look
looks like it will have great ergonomics too!!!
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Sep 12, 2012, 11:16:15
.....(60 to 110 hp)
thats sick!
The Sportster has seen similar percentage gains, since it's now equipped with a Buell top end (Thunderstom system, pre-XB era) and larger-than-Thunderstorm cams.  I estimate it has gone from 40-45rwhp to the 80-85rwhp range, based on what others with similar engine builds see, although I've never had that bike on the dyno.  I like that it still says '883' on the tank, but those mis-matched black heads are a dead giveaway that they're not stock.

Eventually, I may get around to some mild porting and maybe head planing to bump the compression up on the KZ to get a few more HP out of it, but I'm in no hurry with this bike.  I just want to get it running again and have it look cool.  Did anyone ever even make bigger cams for these engines?
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: damarble on Sep 12, 2012, 12:12:04
From what I'm seeing nobody made anything for these lumps, completely neglected. A big bore kit and cam would make my day.

Be sure to document anything you do to squeeze out some more ponies, plenty of 750 guys are wanting more power.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: damarble on Sep 12, 2012, 13:32:46
My mistake, Swivel just informed me that Megacycle does a street cam regrind, #475-20.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: tron97 on Sep 12, 2012, 15:19:26
nothing but straight up respect from me.....(60 to 110 hp)
thats sick!
i will get a hd one day...... i want to get a buell xb12 and chuck it all in a hardtail frame with buell front end and wheels etc...
 you have 2!!!

i still reckon your kz looks better though........
love the tracker look
looks like it will have great ergonomics too!!!

Ive been dreaming of a build with exactly that as well. Buell motor and front end, in a hardtail.

Those are some huge gains. awesome to see
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: Cookie on Sep 16, 2012, 19:15:41
Kawi looks rad, Hallin! Good on ya.
Hope I'm not too late to toss in my opinion, but it's pretty much the same as the others: Stock tank (the peanut makes it look WAY too tall) and that filth green with diamond stitching is strangely hot.
 As far as where to procure that kind/colour of leather, my wife makes a lot of her own clothes and upholstery, so I end up spending way too much time looking around in fabric stores. They'd be your best bet. Im my corner of the world (Ontario), FabricLand and Len's Mills are the places to go for outdoor fabrics. And if they don't have wht you want, they can probably direct you to someone who does.
 Another optin would be to locate a custom auto upholstery shop and ask there...
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Sep 16, 2012, 21:23:50
Thanks, Cookie.  That was my plan.  So far, interior upholstery shops are no help, as they have no 'outdoor rated' materials, but I'm giong to hit up the local boat uphostery folks who did fresh_c 's seat and see what they can locate.  I should be able to find something in or around a city as big as Austin.

I was just up in Torono last week for a quick work-related visit.  To bad I didn't get to look around at all.  It was a whirlwind trip.

Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Sep 23, 2012, 01:20:16
Small progress today.  I just had time this morning to make the front seat hold-down tab and slot.  I've tried it out with the tongue temporarily bolted to the seat pan (final assemby will be riveted, post-upholstery), and it seems to work great.  This keep the nose held down tight, with no side-to-side movement, and allows just the one bolt securement in the back, which I'll probably use a wing bolt, or knurled thumb screw on for easy, tool-less access.

sorry for the small cell phone pic

(http://farm9.staticflickr.com/8315/8014220309_dbaed08ffd_z.jpg)

Not seen here is the slight centerline bend I put in it, both for strength, and to match the same feature in the seatpan.  It's also jogged downward slightly, to avoid the thicker lip of upholstered edge that is to come.  It's simple, but works well.  It's now been painted black, along with a few other minor pieces like the headlight mounting bracket, and old, pitted footpeg mounts that were wire-wheeled clean prior to paint.

Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: tobiism on Sep 23, 2012, 23:27:38
Looking great so far!  I'm just about to get back to working on my 750 twin, Jack Pine style. 
You emailed about the single carb setup.  The single manifold I made was out of 1 3/4" harley exhaust pipes.  They slip right into the rubber carb spigots.  I had it running really nicely with the single Harley 40CV.  It was a tad rich down low but I never had it running long enough to jet it properly.  I do know that I had plenty of grunt down low and nice pull up top. 
You can also run another 750 twin exhaust cam in the intake cam position for more lift and I "think" a tad more duration.  I've got one waiting to go in my engine.
I've taken the whole starter clutch mechanism out, welded the oiling hole in the crank closed and removed the starter.  That with a capacitor for kickstarting the engine to life has really helped reduce weight. 
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Sep 27, 2012, 00:05:40
tobiism, do you happen to still have that 2-1 manifold kicking around?  The more I think about this, the more I like the idea of the single carb.  I'd like to ditch the stock rubber boots and weld on intake flanges, though, to reduce the overall size of the assembly.  Also, because of my electrical box, I may need to angle my carb off to the side, but I'll have to just hold everything up to get a feel for it.

I've been scouring the web for other twins with single carbs and came up with these styles:

(http://i448.photobucket.com/albums/qq208/billeuze/bike%20Stuff/kz440%20single%20carb/ManifoldInstalled.jpg)

(http://i1227.photobucket.com/albums/ee440/junkhead021/IMG00590-20110416-2351.jpg)

(http://www.the-isz.com/maxx/pics/bikes/single02.jpg)

(http://i290.photobucket.com/albums/ll242/gearheadchoppers/bikes/xs650singlecv40.jpg?t=1269963087)

(http://i290.photobucket.com/albums/ll242/gearheadchoppers/bikes/xs650singlecv403.jpg)

So far, I'm liking the last two (which appear to be of the same XS650), as its compact, and looks like it will work with the space I have available.  It even has the same carb mounted that I plan to use.

Should I be concerned about the possibility of the left cylinder running lean with a setup like this?
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: MickyC on Sep 27, 2012, 05:06:39
like a old tiriumph intake ...... nice
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: tron97 on Sep 27, 2012, 16:53:32
As far as Im aware, as long as the intakes are the same length on either side, before the t..it shouldn't run lean..

Where did you find the pictures of the xs intake?
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Sep 27, 2012, 18:25:19
As far as Im aware, as long as the intakes are the same length on either side, before the t..it shouldn't run lean..

Where did you find the pictures of the xs intake?
Google image search for "XS650 single carb" or KZ750 single carb", etc.  There are crazier ones out there of guys doing 4-1 intake manifolds, etc.  They make the work ahead of me look simple.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: tobiism on Sep 27, 2012, 19:29:11
Yeah I still have it, I'll have to dig it out.  Its going to get used on my build, but with the flanges welded on like I emailed you about.  I never noticed a difference in temperature(possible lean condition) between either pipe but my manifold was fairly equal left to right.  Thats the good thing about the KZ twin- the engine cradle is on either side of the engine with no backbone to interfere with a single carb set up.   So for the most part you can run the carb straight back without having to bend it left or right.  I understand about your electrical tray though.   
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Sep 28, 2012, 12:14:40
Thanks, tobiism.  I was going to ask if you might want to sell it for cheap, but since you'll be using it, nevermind.  I think I'm gonna shoot for a left side exit anyway, to avoid the electrical box, keep the rear triangle opening clear, dodge the kicker arm and rear master cylinder, and to really show off the custom carb set up with THIS:

Yup, I'm committed to the idea now.  I just picked this up off Craigslist for $20.  This is actually off an S&S Super B carb, but I'm 99% sure those earlier S&S use the same bolt pattern as the 40mm Keihin CV.  At least that's what my research on some Harley parts sites tell me.

I'll likely use a wire mesh screen & pantyhose 'filter' at the very minimum, and with it turned sideways, I won't get the rear wheel crud slung into it as badly as a rear facing carb might.

(http://farm9.staticflickr.com/8321/8032912185_0c9827631b.jpg)   (http://farm9.staticflickr.com/8178/8032910658_50cdf44ac2.jpg)

(http://farm9.staticflickr.com/8313/8032912121_204723cd76.jpg)  (http://farm9.staticflickr.com/8319/8032912219_a94c9545ef.jpg)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: tobiism on Sep 28, 2012, 13:14:06
If bolt pattern does fit, you will somehow have to make an opening for the bowl vent in the face of the carburetor.  If you cover up that fourth hole with the velocity stack your bowl will airlock.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Sep 28, 2012, 15:29:55
If bolt pattern does fit, you will somehow have to make an opening for the bowl vent in the face of the carburetor.  If you cover up that fourth hole with the velocity stack your bowl will airlock.
Thanks for that reminder.  I think it sits on the same bolt circle as the others, so it should just vent to the outside air without issue (right?).

I may just have to hit it with a tiny round file near that 4th hole, if the flange totally blocks it.
(http://i.ebayimg.com/t/AIR-FILTER-TO-CARBURETOR-GASKET-S-S-Carb-Harley-Davidson-Shovelhead-1977-1984-/00/s/MjUzWDMwMA==/$(KGrHqV,!hUE6cefp35+BOvLd5U7Jg~~60_35.JPG)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: Autotek on Sep 28, 2012, 16:21:05
Been watching your build for a while now and I like everything you have done, except,,, here it comes, the single carb idea. With the amount of time and effort you will have into creating something that is inferior to dual carbs why not just throw on a set of new Mikuni VM34s and kn filters. For around $300 your done and they are so easy to jet and tune. The solid mount between the head and the carb is going to vibrate that single to death and the length of the intake will be a considerable power loss. I know there is something to be said about doing something unique, and it may work well, I just feel like you would see it more if it worked. I inquired about doing the same with my 79 bonneville and my engine guy would not consider it. (atombombcustom.com)  Again I really like what you have done and enjoy reading the thread, good luck and I will keep watching.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: tobiism on Sep 28, 2012, 17:39:05
Sorry but that is just incorrect.  I have done what he is proposing and it works very well.  I used the same carb on the same engine and had even better usable power than the stock carbs.  Nothing shook apart and there was an increase in power by the seat of the pants dyno, not a decrease.  Sure the dual mikuni vm's would be a nice addition, but 300 bucks is a lot of money for a bike that usually costs less than that.

Been watching your build for a while now and I like everything you have done, except,,, here it comes, the single carb idea. With the amount of time and effort you will have into creating something that is inferior to dual carbs why not just throw on a set of new Mikuni VM34s and kn filters. For around $300 your done and they are so easy to jet and tune. The solid mount between the head and the carb is going to vibrate that single to death and the length of the intake will be a considerable power loss. I know there is something to be said about doing something unique, and it may work well, I just feel like you would see it more if it worked. I inquired about doing the same with my 79 bonneville and my engine guy would not consider it. (atombombcustom.com)  Again I really like what you have done and enjoy reading the thread, good luck and I will keep watching.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: tron97 on Sep 28, 2012, 18:53:02
Sorry but that is just incorrect.  I have done what he is proposing and it works very well.  I used the same carb on the same engine and had even better usable power than the stock carbs.  Nothing shook apart and there was an increase in power by the seat of the pants dyno, not a decrease.  Sure the dual mikuni vm's would be a nice addition, but 300 bucks is a lot of money for a bike that usually costs less than that.

Agreed. less is more friends, less is more.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Sep 29, 2012, 00:21:33
I'll be keeping my stock duals in case this doesn't work out, but I'd need to replace some broken / missing parts to get them fully operational, and from what I hear, jets for these are hard to come by.  I have spare jets for the CV, and they are readily available at any H-D shop, as they used them for like 15 years on every H-D sold.  I'll likely have less $ spent in materials to build this manifold than I would to repair the stock carbs.

This bike is never going to be a racer (insert Firestone slam here) so I'm ok with a few HP loss on the top end, as long as it runs smooth.  Vibration?  See previous pages.  My 110rwhp H-D uses a single carb and vibrates WAY more than any parallel twin, and it works fine.  In fact, it made 100rwhp (pre 45mm Mikuni swap) with the exact same carb as I'll be using here, and it has over TWICE the displacement as this 'little' 750, so although the less-direct intake manifold may hinder high rpm flow, I'm sure the single carb will not.

I look forward to making something unique.  Even if its been done by countless others, its still a noticable variation from a stock bike.

I've got a friend building a hardtail out of a 1980-ish 4cyl KZ750, and I've yet to discourage him on the grounds that "performance will suffer".  Of course it will, but that's not the point.  I agree that different does not automatically equal cool, but I'll argue that in this case, it does.

tobiism, I may be hitting you up for baseline jetting and needle setting suggestions as I get closer to completion, if you don't mind.  Note that I still have no functional wiring harness, so it may be a while.

Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: tobiism on Sep 29, 2012, 00:33:42
Its been a while and I don't have any of it written down.  I don't even have that carb anymore.  But I know I had the needle had no shims under it and I had to go smaller on the idle jet(40 maybe?).  I think the main was a 160. 
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Sep 29, 2012, 15:15:28
So this was happenign this morning:

This is the trash pile, and it may get a little larger as I actually run the remaining wires.  There are a handful of 4-way connections that will be reduced to a single connection in the final configuration, but for now I was just snipping away all things related to.....

- guage lights
- indicator lights
- turn signals
- oil pressure switch
- neutral switch
- that weird clutch lever anti-start switch (annoying.  If I can't remember to find neutral or hold the clutch while thumbing the starter, I deserve to be bucked off my own bike when it lurches forward)


The remaining harness still kind of has a lot to it because (for now) I'm retaining....

- electric start
- a traditional key switch
- horn
- brake light (w/ activation switched at front and rear)
- high/low beam (will be simple toggle on headlight bucket)

(http://farm9.staticflickr.com/8179/8036370122_c0a9e09c8c_c.jpg)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Sep 29, 2012, 15:22:49
I also pulled the stock carbs and boots off to take a few measurements and play around with possible carb positions.

Rear-facing, mounted on same plane at the intake ports:
(http://farm9.staticflickr.com/8033/8036366879_8723d7e930_c.jpg)

Rear-facing, mounted below intake port plane:
(http://farm9.staticflickr.com/8319/8036369820_627b972f37_c.jpg)

another view of the same:
(http://farm9.staticflickr.com/8035/8036366707_8d82aae0c7_c.jpg)


Left-facing, mounted at same plane as intake ports.  Right exit hits the kicker pedal.
(http://farm9.staticflickr.com/8176/8036366935_cb23f3d16b_c.jpg)

Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Sep 29, 2012, 16:34:03
I also did a rough knee-clearance check, for the side-exit option, and it looks like I'll be fine, even with a velocity stack protruding 2-1/2"" beyond the carb face.

(http://farm9.staticflickr.com/8181/8036367223_f602e1e5fc_c.jpg)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: tobiism on Sep 30, 2012, 17:23:42
Cool man, I have heard that CV's don't respond very well to velocity stacks when the stack is in the turbulent air.  Might be something to watch for, maybe a half round cover attached to the front so negative pressure doesn't develop across the face of the stack.  I just pulled the manifold out of storage last night and looks like I can bring the carb about 1.5" closer to the head by getting rid of the rubber boots.
Now to see about installing that exhaust cam in the intake spot and retiming the engine!
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Oct 01, 2012, 01:06:10
Cool man, I have heard that CV's don't respond very well to velocity stacks when the stack is in the turbulent air.  Might be something to watch for, maybe a half round cover attached to the front so negative pressure doesn't develop across the face of the stack.  I just pulled the manifold out of storage last night and looks like I can bring the carb about 1.5" closer to the head by getting rid of the rubber boots.
Now to see about installing that exhaust cam in the intake spot and retiming the engine!
I've heard that about stacks too, so I'll keep alternate 'filter' options in mind.  Good luck re-working your own intake.  The exhaust cam swap is on my future, to-do list, but I plan to get it running as-is first, in the hopes that you'll completely document your swap for the benefit of the rest of us KZ 750 twin owners.  :-)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Oct 03, 2012, 10:48:47
My stack arrived, and it's preeeeettttyy.....

oh, and 100 posts!  Woot!
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Oct 06, 2012, 20:51:23
I picked up some bits today.  It's too wide with stock fitting lengths, so I need to trim the male/female interface areas to get to the approximately 5" center-to-center port spacing.  I'll probably also this in the fore-aft axis, to keep the assembly compact. 


(http://farm9.staticflickr.com/8029/8060996439_0ba86a7af6.jpg)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: blipside on Oct 07, 2012, 14:00:47
Interesting to use copper pipes.  Have you heard of any problems with it?  Are the inner & outer diameters the same?  I haven't taken my carbs off yet to see. 
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Oct 07, 2012, 23:47:07
Interesting to use copper pipes.  Have you heard of any problems with it?  Are the inner & outer diameters the same?  I haven't taken my carbs off yet to see. 
I haven't been made aware of anything to be concerned about due to the use of copper.  This is pretty heavy guage stuff, and I plan to support the weight of the carb somehow also.  The intake ports measure just about exaclty 1-1/2" in diameter, so the standard size pipe should work well.  I could just stuff these into the stock rubber boots, but I'm going to try to make some flanges to replace them.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: blipside on Oct 08, 2012, 13:59:18
Cool.  I'm interested to see how things turn out.  I want to move to a single carb also.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: sinbad85 on Oct 09, 2012, 06:17:01
nice progress man!
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: Bobbed_out on Oct 12, 2012, 23:21:26
Looking good...
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Oct 21, 2012, 12:52:00
Minor updates.  I installed some 11" shocks (aftermarket Harley Sportster, Dyna, FXR, type).  These things are crazy stiff, so I'll need to back off on the preload.  I like the stance, and that the swignarm and lower frame rails both sita bout parallel with the earth, but don't like what the lower rear has done to the look of the muffler angle, which used to be closer to parallel with the ground.  I don't have a ton of room to angle them back up, as the fit near the frame and oil pan is very tight.

The pipe 'sag' doesn't actually look this bad in person, but I was trying to get the viewing angle that would make it as obvious as possible.

To get these to fit, I swapped the rubber and steel bushings from the stock shock over to these.  Also, the lower eyelet cylinder needed to be ground down to fit the female swingarm mount.  No big deal, but it took a few minutes to get it all to fit right.

(http://farm9.staticflickr.com/8330/8109013532_911280dc8a_b.jpg)

Comparative photo with stock shock length:

(http://farm9.staticflickr.com/8448/7925002836_a6a6cdaf23_c.jpg)

(http://farm9.staticflickr.com/8332/8109013600_5b3110b2be_b.jpg)

(http://farm9.staticflickr.com/8050/8109013420_a57e0390f5_b.jpg)

Very short travel shocks.  Probably only about 1.5" of functional travel, but who cares.  I'm not building a touring bike here.

(http://farm9.staticflickr.com/8473/8109013358_5ed071d1b9_b.jpg)


All of the tight sports should still clear, even if these things bottom out.

(http://farm9.staticflickr.com/8193/8109013192_5b8d0bf739_b.jpg)

NEXT UP:  I plan to 'properly' lower these forks via internal spacers, and increase the spring preload while I'm at it, because the front end is WAY too soft.  I was going to use this method: 

http://www.xs650chopper.com/2009/06/mulligan-machine-lower-your-xs650-forks-low-buck-garage-tech/

Any concerns with this?  I'll cut maybe 1/2 less from the springs than the amount of spacer added to help stiffen it up.  Has anyone out there done this to a KZ750 twin?  They look to have all the same guts as the XS650 model shown in that link.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: JordanCFH on Oct 21, 2012, 18:13:51
Loving the stance bro! I barely noticed the problem you mentioned with the exhaust, you can probably get away with it....but like you mentioned you were gonna lower the front forks? that may help correct it visually?
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: Pablo83 on Oct 22, 2012, 02:25:20
I think the horizontal pipes looks better.  Why are you swapping the shocks if the new ones are too short and too stiff?
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Oct 22, 2012, 10:47:17
I think the horizontal pipes looks better.  Why are you swapping the shocks if the new ones are too short and too stiff?
As stated, the exhaust angle in that photo is exaggerated.  I can probably raise them back up a few degrees by adjusting my rear hanger under the frame and get them back to near-horizontal again.  Why do the shock swap?  I wanted a low, fat-ish bike and that's not likely to happen with the stock length shocks.  I'm also a heavier rider rider, so stiff springs are ok, and I'll be attempting a near equal increase in fork stiffness soon.

Here is the exact same image, rotated 1.5 degrees, to place the bottoms of the tires in the same plane.  This is a better representation of what it actually looks like.

(http://farm9.staticflickr.com/8470/8112617149_d7d1cba840_b.jpg)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: tobiism on Oct 22, 2012, 10:59:51
Bikes looking great!  I do however recommend a mod to your taillight/license plate bracket.  I give it about 20 minutes of normal road use before it snaps off at the bolts under the tail.  I would add another plate below that connects all 4 bolts together.  This will strengthen it quite a bit more than it already is.  Now its just a diving board.
(http://i12.photobucket.com/albums/a246/tobiism/8109013192_5b8d0bf739_b.jpg)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Oct 22, 2012, 13:00:10
Bikes looking great!  I do however recommend a mod to your taillight/license plate bracket.  I give it about 20 minutes of normal road use before it snaps off at the bolts under the tail.  I would add another plate below that connects all 4 bolts together.  This will strengthen it quite a bit more than it already is.  Now its just a diving board.
I was considering doing something similar to 'box' that section, both for rigidity and also to help hide the rear of the tail lamp's socket. These parts weigh almost nothing.  That tail light is tiny.  Rebuilding this assembly out of steel rather than aluminum may be a good idea too.
 
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: tobiism on Oct 22, 2012, 13:08:07
I say stick with aluminum and box it in.  A steel bracket would be just as likely to break if built in the same manner unless it was gusseted/boxed in.  Even though those parts don't weigh very much, if you put them at the end of a lever and get them vibrating at a good rate its fatigue city. 
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Oct 22, 2012, 18:15:59
I'll knock this out some night when I have some free time.

(http://farm9.staticflickr.com/8467/8114041242_9faf46aa5c_b.jpg)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: sinbad85 on Oct 22, 2012, 19:19:00
love the slammed rear....
just lower the front some more to bring the pipes horizontal  ;)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: tobiism on Oct 22, 2012, 19:38:43
Trackers are supposed to be thrown around with little care towards dragging the ground.  I say lift the rear if anything and get some more ground clearance.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Oct 31, 2012, 21:30:03
I'm going to be working on my wiring this weekend.  Does anyone know what kind of current the starter switch needs to handle?  It's not much, since it just closes the solenoid, and the starter motor current flows through it, not the button, correct?

I have some like this, for the starter and/or horn, but am considering a more flush-mount chrome unit, for a more subtle look.

(http://ecx.images-amazon.com/images/I/21hCKWlIHCL._SL500_AA300_.jpg)

vs.   ...............

(http://ecx.images-amazon.com/images/I/31-uNHvj8KL._SL500_AA300_.jpg)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: MickyC on Oct 31, 2012, 21:34:01
chrome one looks the best. flush look for sure. 
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: PjkF on Oct 31, 2012, 21:37:13
I have one of the chrome ones for my starter button on my little cb350. They have a nice feel when you press them. A positive but smooth click.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: Pablo83 on Oct 31, 2012, 23:41:12
I'm going to be working on my wiring this weekend.  Does anyone know what kind of current the starter switch needs to handle?  It's not much, since it just closes the solenoid, and the starter motor current flows through it, not the button, correct?

I have some like this, for the starter and/or horn, but am considering a more flush-mount chrome unit, for a more subtle look.

(http://ecx.images-amazon.com/images/I/21hCKWlIHCL._SL500_AA300_.jpg)

vs.   ...............

(http://ecx.images-amazon.com/images/I/31-uNHvj8KL._SL500_AA300_.jpg)

The starter button only operates the solenoid so it's only a couple amps. The one in the top picture looks like the kind available at RadioShack.  I tried using a couple of those and they broke pretty quickly.  The bottom on looks solid. 

I like these:

http://www.highwaydirtbikes.com/HDB_Shop/index.php?app=ccp0&ns=prodshow&ref=pb_mom_b

They are very durable and come with a screw on black rubber boot.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Nov 01, 2012, 00:15:36
sold.  I'm ordeing new buttons this week.  Those others were just some I had kicking around already.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: KaaoSkitzofreniK on Nov 05, 2012, 16:45:05
Great looking bike, will be watching closely =)
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: gk45011 on Nov 05, 2012, 20:05:01
What is the silver one off of? That is exactly what I'm looking for when I move some of my bar controls.

GK
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Nov 06, 2012, 17:36:00
What is the silver one off of? That is exactly what I'm looking for when I move some of my bar controls.

GK
Just search Amazon for "normally open button" or something similar.  It should get you tons of hits:

http://www.amazon.com/Amico-Momentary-Button-Switch-Normally/dp/B008DFYEZQ/ref=sr_1_6?ie=UTF8&qid=1352237725&sr=8-6&keywords=normally+open+button
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: gk45011 on Nov 06, 2012, 18:06:21
Damn, Hallin.. Right on point for that exact momentary switch. I looked under momentary before and only got a short list of results.

http://www.amazon.com/SPST-NORMALLY-OPEN-BUTTON-SWITCH/dp/B006WS6FHG/ref=sr_1_3?ie=UTF8&qid=1352239077&sr=8-3&keywords=NORMALLY+OPEN+BUTTON (http://www.amazon.com/SPST-NORMALLY-OPEN-BUTTON-SWITCH/dp/B006WS6FHG/ref=sr_1_3?ie=UTF8&qid=1352239077&sr=8-3&keywords=NORMALLY+OPEN+BUTTON)

GK
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Nov 06, 2012, 19:06:10
I started drilling holes in my electrical box last weekend, and put my red buttons in there as place holders for now.  I may switch to those flush mount ones later, but have plenty of work to do before then.  I'll try to get some photos up again soon.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Nov 07, 2012, 20:16:41
Minor updated to the electrical box.  The two on the left will be starter and horn buttons, and I'll be re-using the factory ignition switch on the right.  The ugly switch spacer will be replaced with something more permanent later.  I've cut up the wiring harness a bunch, but it's not really back together cleanly yet, so no photos of that.

I'm happy that I've been able to keep the visible sides free of clutter. The only things being placed inside are a new Ballistic 8-cell battery, the starter relay, the fuse box, and the bundle of wires.

(http://farm9.staticflickr.com/8478/8165383789_1e2e5fa946_c.jpg)

(http://farm8.staticflickr.com/7257/8165418168_74055eb730_c.jpg)

(http://farm9.staticflickr.com/8205/8165383631_358f30fb0d_c.jpg)

(http://farm9.staticflickr.com/8206/8165419868_5380a0461d_c.jpg)

Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Nov 07, 2012, 21:19:34
*** FORK LOWERING ***

I've yet to see another KZ750 twin dropped internally like this, and I really wanted to lower my stance to equal to or shorter than those seen in previous pages of this thread, but without the fork tubes protruding past the top triple clamp like done by so many builders (including my inspiration, Wrenchmonkees).

Starting point.  I didn't document the removal of the forks from the frame, becasue if you can't do that, you shouldn't bother attempt the simple procedure below.  I stole this method from the folks over at the XS650 forum.

my source of info:  http://www.xs650chopper.com/2009/06/mulligan-machine-lower-your-xs650-forks-low-buck-garage-tech/

(http://farm8.staticflickr.com/7254/8165385205_ae1e5d8254_c.jpg)

First, drain as much of the oil as possible via the tiny drain screw at the bottom.  Pump the tube to squirt it out.  Warning:  this can make a mess if you're not careful, and it smells awful.

Next, unscrew the top cap via a 1/2 drive ratchet, and remove the main spring.  Mine is the non-progressive one on top.  The other is from a 4 cylinder KZ750 that I thought I might be able to use, but unfortunately, the OD of those coils is about .5mm too large to fit inside my fork tubes, despite the OD of both  bikes' fork tubes being 36mm.

(http://farm8.staticflickr.com/7114/8165419432_440a06ed9f_c.jpg)

Now came the tough part.  I had  trouble removing the damper rod bolt from the axle side, as the damper just spun, and I didn't have the 'special tool' Kawasaki recommends to hold it still from inside the fork tube.  So, per the instructions from the guys over on the KZ twin board, I cut down what is essentially a broomstick and jammed it in there, while I hit the lower bolt with an air impact to shock it loose.

This is obviously after the damper rod had been removed from the fork leg. 
(http://farm8.staticflickr.com/7137/8165419306_740e060976_c.jpg)

The contents all laid out in their approximate orientation of assembly.  Not shown is the fork seal, which is still in the casting.
(http://farm9.staticflickr.com/8483/8165384581_7d4cf845c6_c.jpg)

These are the spacers I cut down from some scrap steel tubing.  I've heard of folks using PVC for this, but I feel better about having metal in there.  I don't know why I didn't buy a pipe cutter years ago.  This thing is awesome.  Clean, straight cuts every time.  These spacers will be de-rusted before final assembly.  This was all just a dry mock-up until I can find some 15W fork oil.

(http://farm8.staticflickr.com/7113/8165384471_3e06d03937_c.jpg)

Placement of those spacers:

(http://farm9.staticflickr.com/8206/8165418804_c45bee65bf_c.jpg)

Re-assemble everythig in reverse order, again using the broom stick to allow proper tightening of the lower damper bolt.

Now you're left with a main spring that is a little too long.  Some of this needs to be cut.  As suggested my the XS650 chopper link above, I cut slightly less away from the main spring, as the spacer was long.  Spacer = 1.75".  Spring reduction = 1.5".  This creates a slight increase in spring preload. As a heavier rider, on what I considered to be a very soft set of forks, I thought this would help.  I may add a tiny collar up top to add even more preload but that can wait.

(http://farm8.staticflickr.com/7264/8165418658_c58206e588_c.jpg)

I cut that top section of the main spring with an angle grinder, then ground it as smooth / flat as possible.  The increased preload was not a major change, and I was still able to re-install the top cap with one hand.  Note that I haven't added oil (don't forget that step), but I wanted to show the before & after lengths as seen below.

(http://farm9.staticflickr.com/8344/8165418564_ab43b1eac0_c.jpg)

(http://farm8.staticflickr.com/7132/8165418470_f0bd2a103f_c.jpg)

I still need to perform this on the second fork leg, so full bike photos will have to wait for another day.  These cut springs with added preload feel a tad stiffer than stock, but it's hard to compare without any fork oil.  I'll give my report on that issue when I have some in there.

I hope this helps some foks in the future.

Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: crackerman on Nov 07, 2012, 21:28:48
Nice work on that fork chop. I might have to do that on mine. I've rebuilt a couple sets of KZ forks and with out that "special tool" it's a real pain in the ass to pull them apart. I think I ended up doing something similar to what you did but it took me a while.

If your looking for jets for the BS38 carb I just finished jetting my 79kz. Took me a couple of orders to get the right ones but I found them. I'm running pods and Shorty open mufflers similar to what you got. I used a 50 pilot jet(bs30/96) and 135 main jet(n100.606 under pilot jet)Got them from Niche cycle. Def a big improvement over the stock 125, 45 pilot. I know a lot of people don't like the bs38 carbs, but there's not much to them and there easy to pull apart and clean.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Nov 08, 2012, 00:06:10
Thanks, crackerman.  If I don't do the single carb swap, I'll use these as a good starting point.

OK, so I couldn't wait.  I hacked up the other leg and put it all back together dry tonight:

(http://farm8.staticflickr.com/7111/8165842400_38538ef5bb_c.jpg)

Resting on side stand:
(http://farm9.staticflickr.com/8342/8165842748_250bb989ef_c.jpg)

Fully compressed:
(http://farm8.staticflickr.com/7115/8165842898_ca110e5123_c.jpg)

Lucky me.  Coil bind (or whatever is causing internal fork 'bottoming') occurs here, and no tire-to-header contact occurs.
(http://farm9.staticflickr.com/8060/8165811941_19763cb8f5_c.jpg)

This is better:
(http://farm9.staticflickr.com/8477/8165843414_7f818dc414_c.jpg)

Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: Cookie on Nov 08, 2012, 08:25:32
Looking ballin', Hallin! I like that fork lowering
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: sinbad85 on Nov 08, 2012, 18:27:32
great write up on the internal lowering mate!!!

when i had the stock front end on my bike i called three shops nearby to see if they could do this....

they said it wasnt possible..... :o

if i ever go back to stock front end on this ill be sure to follow your instructions......
looks really good!
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: gk45011 on Nov 08, 2012, 19:43:15
Lucky me.  Coil bind (or whatever is causing internal fork 'bottoming') occurs here, and no tire-to-header contact occurs.
(http://farm9.staticflickr.com/8060/8165811941_19763cb8f5_c.jpg)

How much tire expansion do you get with those tires when they are run and heat up? Looks awfully close in the picture.

GK
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: Pablo83 on Nov 08, 2012, 23:11:45
How much tire expansion do you get with those tires when they are run and heat up? Looks awfully close in the picture.

There was some discussion about this on another site.  I think you're supposed to add something like 3/8" for tire expansion, but more of the expansion is due to centripetal force than heat expansion.  If hallon's ever in a situation where he has the wheel turned this far to the side at highway speeds with the forks fully compressed, he's got a lot more to worry about than melting some rubber to his pipe.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Nov 09, 2012, 00:03:53
if i ever go back to stock front end on this ill be sure to follow your instructions......
If you ever go back to the stock front end, I want your forks.  You know, if you ever visit Texas.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: jr0cket on Nov 09, 2012, 00:17:12
As always, nice work HonkyKong!  Can't wait 'til mine is a roller and we can knock these both out as "done"!
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Nov 10, 2012, 09:02:27
I'm reconsidering my lack of front fender. Not for any functional reasons but just because I threw a Burgundy Sportster (or any Harley with a NarrowGlide) front fender on it and I like the shape and even the color.

Fresh_c has suggested I consider an oxblood color somewhere in my paint and although I was thinking more earthtones it could look pretty good.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: gk45011 on Nov 10, 2012, 16:56:32
There was some discussion about this on another site.  I think you're supposed to add something like 3/8" for tire expansion, but more of the expansion is due to centripetal force than heat expansion.  If hallon's ever in a situation where he has the wheel turned this far to the side at highway speeds with the forks fully compressed, he's got a lot more to worry about than melting some rubber to his pipe.

LOL True, you ain't lying there. I was thinking more of tighter parking lot manuvers after a decent length ride.

Diggin the build, looking tits'

GK
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Dec 19, 2012, 12:33:26
I was thinking more of tighter parking lot manuvers after a decent length ride.
This tight clearance was only with the forks ratched-strapped down to their fully bottomed out position.  Parking lot manuvers allow several inches of clearance.

Please excuse the lack of updates lately.  I've got a baby boy due any day and preparations have taken priority. I'll get back to this after the new year.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: Cookie on Dec 19, 2012, 13:22:29
That's an acceptable excuse, I suppose.  ;D

Congratulations, Hallin and happy hollidays
...
Happy Hallin-Daze?
 ;D
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: gk45011 on Dec 19, 2012, 16:39:15
Congrats and Happy Holidays. Best Christmas gift you could ask for!

GK
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Dec 19, 2012, 17:34:31
Thanks, all.  The little free time I've had has been put to making 'art' from my leftover parts pile.  See link in my sig. 
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: diggerdanh on Dec 19, 2012, 17:41:02
Very cool stuff indeed. I really like the lamps and the clocks. And double congratulations on the incoming child!
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Dec 21, 2012, 21:37:51
Very cool stuff indeed. I really like the lamps and the clocks. And double congratulations on the incoming child!
Thanks, ...to both comments. 

I'm looking into getting hooked up wth some local indie shops who may be interested in stocking or consigning some of my stuff displayed on http://honkykongcustoms.com/

Also, finding a constant source of affordable parts (without turning my backyard into a salvage yard) can be difficult, but I'm making a few scattered connections.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: Scruffy on Dec 28, 2012, 13:49:12
Your fork oil is as close as your nearest auto parts store. I'm 6'2" 240ish, my stock fork springs support me fine with Dexron 2 ATF. Doesn't leak, doesn't foam up. I filled my forks one at a time. Drop them out of the clamps, pull the spring, let the top tube fall into the bottom tube. Stand upright, fill to the top of the upper tube. Extend, add springs, re-install. 5 years without issue. Savage with 15" apes on it...

Bike is looking great so far. Congrats on the baby.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: Fab 5 Freddy on Jul 03, 2013, 10:11:42
Knowing I had lots of parts to strip and re-paint on this project, I invested in a cheap Harbor Frieght sandblast cabinet and went to town.  I few other friends have build projects going on too, so I knew it'd get used enough to justify the expense.  Lucky, wifey is pretty accepting of tool purchases, seeing them as long-term moeny savers, allowing me to do more myself, rather than paying others to do it for me.

Just some of the parts that got sanded and/or blasted and re-painted:

(http://farm8.staticflickr.com/7074/7290565598_fab12fd732_c.jpg)

This engine is actually from another parts bike I picked up for free, if I remember correctly.  It's from a 1980 KZ750G, and looked to be in better shape than the 'B' model's gas burner.  I had it running on one cylinde prior to cleaning the carbs and acquiring a new coil, so I'm confident it will serve me well.

(http://farm8.staticflickr.com/7090/7290564420_82c6e76707_c.jpg)

(http://farm9.staticflickr.com/8149/7290565218_4249dc1294_c.jpg)
What kind of paint did you use on your engine?
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: hallin222 on Jul 20, 2013, 00:42:54
What kind of paint did you use on your engine?
Just some high temp engine paint from my local auto parts store. Maybe it was the PJ1 VHT stuff in satin black. I forget exactly. Sorry.

Excuse my lack of updates. Life took up all my free time for the first half of 2013. The new baby plus an ever increasing workload at my day job leaves little tome for much else. I'm anxious to get back to the KZ though. Maybe more updates in the next few weeks.
Title: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: Beaner242 on Aug 21, 2013, 14:49:26
Love the build. I just read through the whole thing instead of doing my job. LOL. I've def subscribed and am waiting patiently for any updates. Oh and congrats on the new addition. They will definitely suck up all your free time. But in a couple years you will have a little helper.
Title: Re: Project: "HonkyKong" 1979 KZ750 B Twin (brat-tracker-thingy)
Post by: fresh_c on Apr 02, 2017, 08:36:43
Updates!  We need updates!