CB360's-from build to blog - 2013, MDS (Mo Dumb Shit)

620dark

You can always get it running with time or money.
No wonder the 360s love the synthetic oil so much. I was worried my timing was advanced from the amount of heat the 360 was kicking out.

I didn't have any luck finding a Dynatech or other electronic ignition setup anyway. One guy had a 10+ year old unit "new in the box" that he would "let" me have for $250 ::) At least I picked up a turn signal / license plate bracket for the CBR900.
 

crazypj

Split personality, I fake being smart
Fitting 100w headlight to Katana, thought I'd be 'clever' and wire clutch safety switch through relay so headlight goes out when clutch pulled and button pressed
Well, that didn't work (without fitting a relay to power relay to work high/low ::) )
Back hurting today, need to find my painkillers :(
 

crazypj

Split personality, I fake being smart
Finally got Katana running, pissed petrol everywhere, pinhole in fuel line :(
It's molded 90 degree, I made a union to fit tap and used the old fitting soldered in to make a 90. ;D
Trying an experiment, (worthy of Ichiban ;) )
Had some heat barrier but not enough to do all of tank bottom, so, aluminium foil tape for AC got used.
No idea if it will help keep fuel cooler or if it will fall off tank base when hot? (I did spend some time de-greasing base of tank)


Fitting soldered in


Finished piece


It kept me busy and amused for the day ;D
 

BlueCB360

New Member
The glue on that true "Duct" tape is unbelievable.

It should hold up to the temps just fine.

I hope you never want to get that stuff off the tank.
 

crazypj

Split personality, I fake being smart
That's good to know, didn't seem so great for duct repair, probably didn't get all the dust off.
I cleaned and de-greased tank so hopefully it will 'never' move 8)
Bike seems to be running fine considering it hasn't been ridden for over a year, guess starting it up every couple of weeks helped prevent carbs s gumming up.
Damn elbow is hurting where surgery was performed, worse than hand (that's only tingling. same as 3+ yrs ago)
Only did 10 miles to bike 'club' and 10 miles home, back not too bad last night but not so good today. May be a long time before I can ride any decent distance (100+ mile club run, etc) :(
 

timberwolffxdl

New Member
Re: Yet another CB360 ( or two?)

crazypj said:

3. 2mm oversize pistons. Cylinder has been bored but not honed to size
what piston to wall clearance did you bore to and what clearance to finish to after the hone?
 

crazypj

Split personality, I fake being smart
Bore around 0.002" undersize and hone to 0.0015"~0.0017" bigger than piston (about 0.002"~0.003" honing)
There are pics in here somewhere
 

timberwolffxdl

New Member
I read through the thread a few weeks ago, but honestly, 54 pages long...it's a bit of work to find specific info to just this part of the build. I have been running through google, and EVERY thing I come across about the GS850 pistons has a response where someone says you've done and posted details. But I can never find a good, clear writeup on just that mod. This thread is the best I've been able to find.

Have you done any sort of tech article on just the big bore mod? I'd be interested in seeing something with the details of how you did it. Piston selection, rings, gaskets, what got machined (heads, cylinder base.head mating surface) any head mods, etc.

Heck, I'd even help as yours is probably together and mine is ready to get started to step by step before and after pics can still be taken.
 

Sonreir

Oregon
The GS850 pistons are pretty much a straight swap. They have a slightly higher deck height than the CB360 pistons, so make sure you don't take too much, if any, metal out of the stack. Other than that, you're just boring the cylinders to accept them.
 

timberwolffxdl

New Member
Sonreir said:
The GS850 pistons are pretty much a straight swap. They have a slightly higher deck height than the CB360 pistons, so make sure you don't take too much, if any, metal out of the stack. Other than that, you're just boring the cylinders to accept them.
seems I've read about shaving the head .025"? also, will pretty much any vanilla gasket set work? I may be remembering wrong, but I thought I saw something where PJ said to use other gaskets either for the head or base. I've also seen some folks talk about doubling up a gasket to maintain p-to-v clearance.
 

Sonreir

Oregon
Email Lani at Copper Gaskets Unlimited. You won't be able to use stock head gaskets after boring the cylinders 2mm over. I would skip shaving the head until after you complete your clearance checks. It's a lot harder to add metal back on than it is to take more off (ask me how I know).
 

timberwolffxdl

New Member
Sonreir said:
Email Lani at Copper Gaskets Unlimited. You won't be able to use stock head gaskets after boring the cylinders 2mm over. I would skip shaving the head until after you complete your clearance checks. It's a lot harder to add metal back on than it is to take more off (ask me how I know).
which is why I have 3.5 motors in the garage and haven't sold any of them yet. Easier to pull a part off another motor than add metal ;D
 

crazypj

Split personality, I fake being smart
timberwolffxdl said:
which is why I have 3.5 motors in the garage and haven't sold any of them yet. Easier to pull a part off another motor than add metal ;D
Pity your so far from Florida, I need a spare motor ;)
Get a 1/16" thick head gasket with a 69.5mm 'hole' and a 1/32" copper base gasket, stock sizes
Lani has made quite a few of them by now (I can't remember if I've had 4 or 5 and I know he did at least 5 more in one session)
 

BlueCB360

New Member
Yeah, he made a copper gasket for me too.

I still have the GS850, you want me to drag it down to Florida in Oct?
 

crazypj

Split personality, I fake being smart
Had a fun afternoon making and fixing electronic stuff.
Modified my soldering iron to have low and high power (cut lead, fitted a lamp switch and a bridging diode, when 'OFF" AC goes through diode and cuts power by roughly half. Couldn't get accurate temps as tip is so small but it looks like 500+f to less than 300f.


Then I repaired an LED running light, all 3 LED's were burned out
It was probably 9~10 volt being run on 12~14 volt.
I cut copper track and fitted a resistor so it now works fine up to 13.7 volts.
Original LED's were 3mm but there is room for 5mm, may have to modify lens (when I find it ;D )

The circuit board is probably about an inch long, picture is enlarged a few times ;D

After that I removed clear LED's from some instrument lights I bought and fitted superbright amber LED's in place (with correct resistors) plus fitted new leads to the 'neutral' light (green LED, wires were only held on by the heat shrink tube ::)
My first actual foray into electronics that worked exactly as expected 8) ;D
All simple enougth stuff but I needed to do something I could actually finish for a change
 

crazypj

Split personality, I fake being smart
Forgot to mention, also picked up a right side footrest hanger for a CB400f to fit on 'Blue Bike'.
Moves footrest back about 3"~4" not as radical as full on rearsets
 

crazypj

Split personality, I fake being smart
Fuck, fuck, fuck, fuck, fuck, fuck, fuck
My CJ391 has been stolen
It's in Britain somewhere. Was stolen from shed in South Wales
I'm wondering if it was the same people who stole the last one a few years ago.
I didn't contest that so they got a 'free bike'
This one I'm really pissed about

It's real distinctive as it has modified RD350 carbs, 70mm pistons, 'custom' exhaust, Maico rear mudguard, GS125 headlight Yamaha XT350 handlebars, CB250 tank, orange seat, plus, it's yellow
 

irk miller

You've been mostly-dead all day.
DTT BOTM WINNER
Fucking A, PJ. I'm really sorry about this.


Sent from my iPhone using Tapatalk
 

crazypj

Split personality, I fake being smart
No word about bike :(
Replaced some missing images that Photobucket 'lost' a while ago, about half way through thread
 
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