86 GSXR 750 suspension to my 79 1000, should I?

[justin caise]

Just found a "great" deal on 86 GSXR 750 frnt end swingarm with wheels brakes tires and I'm wonderin if it's the way to go.
The 86 rear tire seems a bit narrow for my tastes 140/70-18 rear and 110/80-18 front the seller says. I can't even recall what the girth on my stock 1000 is right now [at work, shhh.]
Any idea gentlepeople (I almost said gentlemen) how wide I could go if I use the 86 swingarm and upgrade to diff wheel and tire? Like hopefully to a 4.5" wheel or even 5.5 \\/
Yeah, I'm aware that I'd need to fab some rear shock stuff - looking forward to that.
Also the 86 tire sizes being 18's kinda tall huh?
So about the front end - is 86 one of the years that had a "too short to be a healthy add on" front end?
Is the 86 a good donor bike for GS1000 susp mod?
P;ease excuse my ignorance - rather new to the old buggers.

[80GS1000]

Just found a "great" deal on 86 GSXR 750 frnt end swingarm with wheels brakes tires and I'm wonderin if it's the way to go.
The 86 rear tire seems a bit narrow for my tastes 140/70-18 rear and 110/80-18 front the seller says. I can't even recall what the girth on my stock 1000 is right now [at work, shhh.]
Any idea gentlepeople (I almost said gentlemen) how wide I could go if I use the 86 swingarm and upgrade to diff wheel and tire? Like hopefully to a 4.5" wheel or even 5.5 \\/
Yeah, I'm aware that I'd need to fab some rear shock stuff - looking forward to that.
Also the 86 tire sizes being 18's kinda tall huh?
So about the front end - is 86 one of the years that had a "too short to be a healthy add on" front end?
Is the 86 a good donor bike for GS1000 susp mod?
P;ease excuse my ignorance - rather new to the old buggers.

I'd pass on that 86 GSXR 750 gear and get later stuff. Modern sportbike rubber is all in 17" sizes so finding good tires in those 18" sizes would be a PITA.

For the front end, start scouting for a 89-95 GSXR 1100 complete front end. Get the entire thing complete if at ALL possible, as buying parts piecemeal is a pain and pricey. These GSXR 1100 front ends are a straight-bolt on to the GS headstock, so it'd be pretty easy. And the rim sizes are 17", so finding good radial tires in that size is a piece of cake. Plus they're about as long as the GS forks, so no risk of dragging your exhaust in the corners or on sleeping policemen. Shorter forks require that you jack up the back to make up the difference in ride height, or get a custom exhaust made like a 4 into 2 into 1 for more ground clearance.

If you feel like being a bit more adventurous, grab a complete GSXR 1000 (2001-2007) front end. This is a bit more tricky, as you have to find a custom bearing to match up the dimensions of the GSXR 1000 steering stem with the dimensions of the GS headstock. And you need to press the lower bearing race off the GSXR stem and replace the lower bearing with a tapered bearing. From there, it's a bolt-up deal. The brakes are amazing (think retina prints on your visor, cartoon-style) and forks have come a LOOOONG way since these bikes were originally built. They're way stiffer than the stockers. If you go down this route, let me know and I'll give you more detail.

For the back end, you might as well go as modern as possible. This'll let you run a 180/190 radial on a 6 by 17 inch rim. and a powerful modern rear brake. The new back ends are plentiful, easy to find, and cheap, which is a plus, not to mention their superior performance. The new swingarms are super stiff and well braced compared to the older GS and GSXR swingers, and the shocks are really well made.

I'm at the beginning of doing a 2006 GSXR 1000 monoshock conversion on the rear of my 80 GS1000.

Quite a few changes and mods need to be made to do the monoshock conversion. It appears * that the 2006 GSXR swingarm minus the cap bushings inside the swingarm is the same width (225 mm) as the stock GS1000 swingarm, which'll make that part easy. I'll post a comment in my thread when I test this out. The GS axle bolt is smaller in diameter than the GSXR pivot bolt, so you'll need to make a bushing that makes up the difference so the GS pivot bolt can be used inside the GSXR swingarm. Or drill the pivot bolt holes on the frame (yikes) to make them bigger to accept the GSXR pivot bolt. You'll need to make some spacers to mount the lower part of the shock to the centerstand bracket, and design an upper monoshock mount bracket for the top mount of the shock that will be bolted onto a new frame cross-spar and then welded to the frame. Your electricals will need to be moved from behind the side panels to make room for the monoshock. You'll also need to remove the airbox, and therefore run pod filters on the carbs. You'll need to do a 520 sprocket and chain conversion. And play around with your ride height to make sure your ground clearance, and rake/trail numbers are healthy.

You can follow my thread as I go step-by-step through the monoshock conversion, and the rest of the project.

Some pics of YoshiJohnny's bike with the GSXR 1000 front and rear ends installed, and a pic of my bike mid-surgery with the same mods going in.
YJ's bike is an '83 GS1000, mine's (go figure) is an '80.

YJ, hope you don't mind me plugging your bike m8:



Scalpel please:

[justin caise]

Hey 80!
thanks for the suggestions. Yeah, I've been watching your thread there. Just still trying to discern between the years and worthwhile upgrades. My general take on most of the whole thing now is form follows function for these big ol crotch rockets. I'd like my GS 1000 to be strong in the low and middle of the power band Exhaust and jetting, etc. and handle reasonably well in the country rd corners. Not a track bike screamer and not wheel standing streetfigher either. Sport cruiser still I guess just better at it.
(Form first and function out the window when I get around to building my Exile American V-twin clone. You see, I like all styles of bikes.)
So if going to the trouble of a suspension change over one should put up the necc push for the best performing equip available (within reason and budget of course.)
Now back to our regularly scheduled GS1000 streetfighter idea w/ picture thread.

http://www.thegsresources.com/_forum/showthread.php?t=97905

[80GS1000]

Hey 80!
thanks for the suggestions. Yeah, I've been watching your thread there. Just still trying to discern between the years and worthwhile upgrades. My general take on most of the whole thing now is form follows function for these big ol crotch rockets. I'd like my GS 1000 to be strong in the low and middle of the power band Exhaust and jetting, etc. and handle reasonably well in the country rd corners. Not a track bike screamer and not wheel standing streetfigher either. Sport cruiser still I guess just better at it.

What's your setup right now in terms of modifications? Is it mostly stock? Got a pic of your bike? Pods, a jet kit, your stock carbs, and a good 4 into 1 pipe will give you plenty of low and middle end grunt.

(Form first and function out the window when I get around to building my Exile American V-twin clone. You see, I like all styles of bikes.)

Cool! Post some pics of your project when you get started on it - choppas look sweet.

So if going to the trouble of a suspension change over one should put up the necc push for the best performing equip available (within reason and budget of course.)

Late model stuff then, sounds like. Easy to find, relatively inexpensive, and great performance.

Now back to our regularly scheduled GS1000 streetfighter idea w/ picture thread.
http://www.thegsresources.com/_forum...ad.php?t=97905

Don't want to steal your thunder, this is *your* thread. :-D Hope I can help you out.

[YoshiJohnny]

I would have to agree about the early GSXR750 stuff....might be cheap, but you aint gonna gain anything with the wheels except a little bit of weight saving. Wheel rims are much the same width as standard GS ones and are 18 inch so decent modern rubber is not readily available. I think the front would be a little short without jacking the back end up to compensate and you will scrape the exhaust everywhere. Seem to remember the stem is a different length on the bottom yoke (tree) as well but don't hold me to it. Later GSXR stuff is much easier to fit and works well (so far!!), I can keep up with tricked up supermotards round the twistys and runs straight with no wobbles up to silly speeds on GSXR1300 Busa gearing!!

Go for it fellas

YJ

:-D

[Guest]

Bridgstone makes 18" Pilot Roads for the front and back...you can safely put a 160/60-R18 on the back rim (IF it is the same width as the '87 rear rim) I got a smoking deal on the full set up from an '88 1100, with '87 rims, though. Racetech emulators and such, and I am using my swing arm. All the suspension and brakes came from the same bike, rims from another.....good luck on your search!!

[80GS1000]

Justin-

Have you decided yet what you want to do in terms of suspension mods? Did you get that 86 Gixxer 750 gear?

[Commodus]

Heh, looks like I'm the dissenting voice here.

I would argue that the benefits of the later suspension over well set up late 80s stuff is all but invisible on our old nails. The big deal here is going to radial rubber, that's where the gains really come from. AND the early GSXR stuff is easier to find and cheaper.

In addition, remember that most of the racers from the period we're interested in used 18" wheels. So that lends some period-authentic street cred, I would say. My Kat is getting late 80s GSXR stuff when I go that route, probably next winter.