1980 GS550E + 2000 Katana 750

scott s

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The 750 engine I'm using is air/oil cooled. It has the same dimensions as the 600 Katana engine. I am using a set of carbs from an earlier model for ease of tuning.
 

scott s

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And now I have shock mounts. Ended up buying a second set of clevis mounts, turning one set from a I_I shape to an L shape, then boxing it in. Both sets of clevis' were welded together and then welded/boxed onto the swingarm.

Now...on to the engine fitment!





 

scott s

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So, this happened....





Found a local guy that's an engineer and has some gab skills. He's doing all of this from his home garage. I couldn't be happier. He truly "gets" what I'm trying to accomplish and is doing quick, neat work. Today was just a "touch base and check on progress" kind of day and I'm thrilled.

The rear upper mount is very nice and it, along with the lower RH mount, will be removable and make getting the engine in and out very easy.



 

scott s

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The front mounts are the stock Katana mounts that he cut/modified and welded. The rubber dampener inserts were rather worn, so he made these aluminum spacers.




He wasn't quite happy with that though, so he made theses Delrin spacers.

 

scott s

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I think it's gonna look really cool...and function great, too. He's still working on two of the lower middle engine mounts. We also checked header fitment and discussed the oil cooler mounting today.
He's already checked chain alignment with a straight edge. Today, we ran the chain across the sprockets (I'm gonna need a longer chain) and it clears the frame, but is tight. The upper run can probably be cured with an acetylene torch and a ball peen hammer. The lower run may require some minor clearancing around the foot peg mount bosses. Switching to a 520 chain really helped.
I'm also going to take the muffler with me next time I go and discuss a rear hanger for it.
Oh, and he's going to work on the steering stop to prevent the larger forks from hitting the tank.



 

scott s

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Picked up the GS/Kat project from the welder about a week ago. I'm really happy with the quality of his work and his solution to some of the things we faced. It helps when your welder is an engineer, too!



 

scott s

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When I got it home I couldn't help but slap on some bodywork and see what it might look like!


 

scott s

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Been kicking around ideas for the gauges/dash. I have these early GSX-R 750 clocks, and I found a speedo drive that fits my wheel, but they're incomplete. I'd have to come up with some idiot lights and some sort of pod/dash/flyscreen to finish them off.
I like the idea of old school analog gauges. But it might be easier to go with something modern. There's also the possibility of fitting a dash from a Bandit 1200 or similar.
This is something I still need to figure out.

 

scott s

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Then I stripped it all back down again.



I spent a couple of hours this morning making my fingers sore. When I stripped the wheels a while back, I noticed some oxidation. I went through a couple of grades of sand paper, then switched to several stages of SkotchBrite pads.
At this stage, they have a nice brushed/satin finish. I'm 95% sure I'm going to stop there. I need to decide whether I want the centers black or graphite.


 

scott s

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Also, since I originally intended to fix up the GS550 with more of a stock vibe, I had started collecting some parts before I went the GSX750 route.
I was tired of tripping over parts in the garage, so I took the spare frame I got from eBay and cleaned it up and painted it. I rebuilt the forks with new seals/oil, Sonic spring and valve emulators. Found a nice set of used Koni shocks for the rear. Cleaned and greased all bearings, etc. Cleaned, painted and polished up the stock wheels and installed slotted rotors from a later model.
Turned out pretty nice considering I used parts I had on hand and lots of elbow grease. This one will get the stock GS550 engine (after I re-seal it), carbs and exhaust, plus some custom bodywork. In the mean time, it's easier to store a rolling frame than piles and piles of parts.






 

scott s

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It doesn't look like much, but this pic represents working rear brakes with a much larger swing arm.
I used a GS850 rear master (same as the 550 but with a longer push rod) and we bent the actuator arm from the 550. It's tight, but it clears. I'll use a banjo bolt style brake switch, since there's nowhere for the stock spring to fit now.

 

scott s

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I ran into a snag fitting the '95 BST-36 carbs. The manifolds that come with the carbs don't match the head. There's a HUGE mis-match to the ports. The old manifolds are taller and would cause the pods to hit the frame.
Suzuki did a lot of superseding over the years, and parts were often used, discontinued, then brought back on another model, only to be superseded again. It makes researching parts VERY difficult.
I'm going on the suggestions of a friend and I ordered a set of Bandit 1200 manifolds. Let's hope they work, since the 36's have been rebuilt and I bought a jet kit for them.

 

scott s

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I did pick up a Giuliari seat, though!



And I polished up the lips of the wheels to a satin finish, paint detailed the centers, and installed the rotors, which had also been detailed.
New Shinko 712's were also installed.


 

scott s

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Fitted a GSXR 1100 fender to the Katana forks for more of an old school look.





Finally got the correct manifolds to fit the BST-36 carbs to the 750 head. These are used on GSXR1100's and Bandit 1200's.



The filters are a tight fit to the frame, but the motor goes where the motor goes. There's no way to tilt it forward or move it down anymore. The mashed part won't be visible once the tank is on.




And speaking of the tank, I'm going to have to raise the back slightly. The petcock would foul the filter otherwise. I'll probably trim off that small ear on the end of the lever for more clearance, too.



And come up with some sort of bracket here to lift the tank slightly.



Once I get that sorted, it'll be time to pull the engine and get it on the stand for detailing and a tune up, and to get the frame and swing arm painted up.
 

scott s

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First, I want to apologize for the pics. My phone sucks and the light in my garage tends to wash it out. It's nearly impossible to get good pics in there. It looks like I used a potato instead of a camera!

I have received a few comments/PM's about the shock and swing arm angle and length. I agree that it's steeper/longer than I would like, but there's a ton of work getting it centered and clearancing for the chain. Many of the pics showed the bike on the lift/center stand and the swinger drooped. I considered a different swinger; GS1100E, Bandit 1200, etc., but at this point I think it would be easier to work with what I have.

I put the wheels back on the bike and set it down on it's on weight. The jack is just keeping the bike from tipping over, not lifting it at all. The shocks are 14" and set on the medium setting. I *still* feel like we could have laid down the shocks a bit more but, as you can see, the shock and swingarm angle aren't as bad as when it was on the center stand/lift and not rear wheel in.

This is workable. And if it just handles too poorly or annoys me too much, I think it would be easier to go with some 13" shocks and maybe even have the chain adjuster slots machined longer and the end of the swingarm cut off a like amount. That would shorten the wheel base, lower the stance and lessen the swing arm angle. All without having to start from scratch.





 

scott s

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As often happens with projects, the work it takes to get it done doesn't look like much. But now the tank clears the carbs, the lines of the tank and seat are nice, the seat latch works, and the petcock (mostly) clears the air filter.

I ended up using BST-36 carbs, Bandit 1200 manifolds, RamAir filters and Bandit 1200 rubber velocity stacks. The OldSkoolSuzuki guys swear that the RamAir filters/velocity stack combo makes for MUCH easier tuning. The RA filter squishes just enough to clear the petcock and leaves more than an inch behind the stack on the #1 throat.




I also re-did the top triple. I put the bar risers in a different spot and used a Bandit 400 dash. It's nearly invisible in the pic, but that black area between the gauges and the triple are idiot lights. The 4oo gauges use a cable drive speedo and the plug is (supposedly) nearly identical to the Katana plug and is supposed to be easy to swap around a wire or two to make it plug and play.
They also have nice cups to hide the rear of the gauges, and it keeps it all in the Suzuki family.


 

scott s

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I've been pretty side tracked on projects lately. Been thinking about moving in a year or so and spent several weeks doing a "purge" around the house and garage. MASSIVE amounts of stuff to the dump and to Goodwill.
Anyway, I've decided to work on the 1980 GS550 donor/spare parts bike this Winter. That way, I can maybe move it out next Spring and have one less thing in the garage. And one less project to worry about.

Got the stock GS550 engine on the stand. It doesn't need a rebuild, but it was a leaker, so I'll re-seal it this Winter with fresh gaskets and such. The carbs are currently getting rebuilt with new diaphragms.
The frame is a 1980 GS550E frame but, unbeknownst to me, that was the year that Suzuki stopped differentiating between the E and L bikes on the VIN number. I ended up with an L frame and an E donor.
We cut the upper tank mounts off and I have a plan to get the tank rubber mounted through those lower holes, where it needs to be for an E tank.



I have a frame loop with a slight kick up that I will have welded on once the tank mounts are sorted. I will run a bobbed rear fender and a small tail light.




Zip Dawg approves.

 

scott s

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This bike is my inspiration for the spare parts bike. I will be able to run the stock carbs, exhaust and even the plenum, so that should really simplify tuning.
I'd say I have about 90% of the parts needed to finish this one.


 

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