83 Katana 1100 Race Build-Rim Change

[D Nuts]

upgrading to 4.5 inch sv650 rear with stock swing arm.

does anyone know which size spacers and how i can deal with my brake arm and will sprocket alignment be a problemo? thnx

[Buffalo Bill]

That don't seem strong enough…

The SV650 weighs less than 400 LB. and only makes 70 HP.
The GS1100 weighs 550 LB. and makes 110-125 HP.

That's a 150 LB and 40-55 HP load increase.

You think that SV650 swing arm won't twist or collapse?

Bill

[D Nuts]

stock Kat swingarm..gotta run period

The SV650 weighs less than 400 LB. and only makes 70 HP.
The GS1100 weighs 550 LB. and makes 110-125 HP.

That's a 150 LB and 40-55 HP load increase.

You think that SV650 swing arm won't twist or collapse?

Bill

[Billy Ricks]

You'll probably need about 1/4"-3/8" offset on the front sprocket. You can just bend the torque arm to clear the tire. About the only spacer you have any control over is the one on the right side between the hub and the caliper hanger. Use the SV part if it fits the axle you'll be using. You may have to spread your swingarm a little if it's all too tight in the arm.

[D Nuts]

Im not sure what is viable from an axle perspective Stock vs SV.

You'll probably need about 1/4"-3/8" offset on the front sprocket. You can just bend the torque arm to clear the tire. About the only spacer you have any control over is the one on the right side between the hub and the caliper hanger. Use the SV part if it fits the axle you'll be using. You may have to spread your swingarm a little if it's all too tight in the arm.

[Billy Ricks]

Im not sure what is viable from an axle perspective Stock vs SV.

If your stock axle is different than the SV then you can swap the GS bearing sizes into the SV wheel so you axle will work. You can find the bearing sizes the two wheels use through Alpha or one of the other parts houses.

[Billy Ricks]

The axle on the SV looks to be 20mm, same as you should have. That will let you use the SV spacer which may be different from yours. You can start with your stock spacer and see if the wheel is centered with it.

[GregT]

Be careful and check with your club tech guy....your rules on line say solid spoke mags - and I'm pretty sure the SV's are hollow.

[D Nuts]

Holy crap. I've bought my rims already because I thought solid was not multi spoke. He approved the sv front end but maybe you're right & he may not approve the rims as well. Thnx

Be careful and check with your club tech guy....your rules on line say solid spoke mags - and I'm pretty sure the SV's are hollow.

[John Kat]

Holy crap. I've bought my rims already because I thought solid was not multi spoke. He approved the sv front end but maybe you're right & he may not approve the rims as well. Thnx

The one thing you need to watch carefully will be ground clearance.
On my GS 1000 XP I've used GSX R 1100 K suspension and wheels and allthough I used "in-board" exhausts from a 1100 Kat, I have less than 45° static lean angle.
On the road it's OK but for racing it's an invitation for disaster...
My rear wheel is also 4.5 inch wide and I use a 13 mm offset front sprocket made by AFAM ( #25003-16T).
This is for a 530 chain by the way!
Here's a picture with a 4 into 1 exhaust but the issue of ground clearance remains.

[D Nuts]

I guess my build is suppose to be challenging and fun. I anticipated challenges, but its been way more difficult than I thought. Clearance is certainly an issue on the track as although I'm not likely to podium, I do like to have some fun and used to leaning my ex 06 R6 to the max (and more). Getting the Kat to a comfortable race level for me has been brutal. My build map keeps changing even after I believed I had things within rules and parts bought. Im now seriously thinking about abadoning to either pick up a more prepared GS (like a 1k or 1100) with less to do despite my dream being to race a Kat. Not to mention the forecasted cost, has got out of hand. Really bummed out about it, but really appreciate you guys sharing your experiences and sharing your knowledge. It would be FAR worse to have it built to find out it was a nightware to ride for all this $ and time.

The one thing you need to watch carefully will be ground clearance.
On my GS 1000 XP I've used GSX R 1100 K suspension and wheels and allthough I used "in-board" exhausts from a 1100 Kat, I have less than 45° static lean angle.
On the road it's OK but for racing it's an invitation for disaster...
My rear wheel is also 4.5 inch wide and I use a 13 mm offset front sprocket made by AFAM ( #25003-16T).
This is for a 530 chain by the way!
Here's a picture with a 4 into 1 exhaust but the issue of ground clearance remains.

[GregT]

Keep at it - you'll get there.
Clearance....I've just put 17's on our GS1000 and we're better than before because of other changes.
Front end - standard fork length, progressive springs which IMO are just a tad soft for race use so 1 in spring spacers have gone in.
Back end - 360mm Gazi shocks....call them elevator heels.
It already had rearsets and I'd removed the alternator rotor and made a short cover on the left.
The pipe on it had parallel header downpipes and the bottom bend of the LHS decked so that got cut & shut & tucked in tighter.
Currently the peg decks on the left - just before the motor. On the RHS the pipe belly touches again just before the ignition cover.
First time I ran it after changing wheels I used the shocks in 330mm length. That told me what needed moving then the shock extension clevises went on.
Geometry is approx 24.5deg rake and around 85mm trail - still very stable.

[D Nuts]

In addition to clearance..

I originally tried starting from my wheels up as I really wanted 17's (3.5 / 4/5) as per the rules so rubber would be decent and turning the bike wouldnt be brutal.

So, I need SOLID spoke rims of this size and felt it would be best to find the rims of this size that could bolt into (calipers to consider as well) a front end that had 41mm max tubes not adjustable thought. Upside down forks are not permitted and I think early Gixer were 43 mm and maybe adjustable. This is why I went with the SV650 front end, but now I realize I cant run the hollow SV650 rims I bought..?

"Non cartridge type forks to a maximum diameter of 41mm. Anti-dive and external adjusters allowed. No USD forks. Post period forks meeting these restrictions will be accepted."

Keep at it - you'll get there.
Clearance....I've just put 17's on our GS1000 and we're better than before because of other changes.
Front end - standard fork length, progressive springs which IMO are just a tad soft for race use so 1 in spring spacers have gone in.
Back end - 360mm Gazi shocks....call them elevator heels.
It already had rearsets and I'd removed the alternator rotor and made a short cover on the left.
The pipe on it had parallel header downpipes and the bottom bend of the LHS decked so that got cut & shut & tucked in tighter.
Currently the peg decks on the left - just before the motor. On the RHS the pipe belly touches again just before the ignition cover.
First time I ran it after changing wheels I used the shocks in 330mm length. That told me what needed moving then the shock extension clevises went on.
Geometry is approx 24.5deg rake and around 85mm trail - still very stable.

[D Nuts]

91-93 F2 entire front end, brakes and rim?

what about the rear? swing arm, rim and caliper?

is this the best option within the rules?

hmmmm

In addition to clearance..

I originally tried starting from my wheels up as I really wanted 17's (3.5 / 4/5) as per the rules so rubber would be decent and turning the bike wouldnt be brutal.

So, I need SOLID spoke rims of this size and felt it would be best to find the rims of this size that could bolt into (calipers to consider as well) a front end that had 41mm max tubes not adjustable thought. Upside down forks are not permitted and I think early Gixer were 43 mm and maybe adjustable. This is why I went with the SV650 front end, but now I realize I cant run the hollow SV650 rims I bought..?

"Non cartridge type forks to a maximum diameter of 41mm. Anti-dive and external adjusters allowed. No USD forks. Post period forks meeting these restrictions will be accepted."

[Greg B]

'87 GSX-R 1100 forks & wheels would work rather well, I would think. Although the wheels are 18" IIRC.