gsxr forks for my 1150 efe

[Gerry]

Hey,
I just bought a set of 86-88 gsxr 1100 forks for my 84 1150 efe. I did a search on this upgrade and have read that this should bolt right up. Install a stop then drill and tap the top triple clamp for the for the bars. I guess I'll have to look for a 89 17" wheel and spedo drive (not to sure about changing the instruments though, might have to live with the error in speed). I was just wondering if anyone has done this to an 1150 that can give me more insight than I have already received on this great site.

Thanks in advance Gerry

 

[Anonymous]

I have not tried it yet but I am curious to see how it goes.

 

[Gerry]

I'll keep you posted on how I make out. The front end should get here this week. I think I made a mistake already, the forks are off a 86 to 88 gsxr 1100 and I think they had a 18'' front wheel and I wanted 17" all around. I'm not sure but if this is true than it will be interesting putting the brakes on the forks. I don't have the wheel or the rotors yet and I got 89 gsxr 1100 calipers. Guess I'll wait tell the stuff gets here and get the tape out.
Gerry

 

[Billy Ricks]

The '86 and '87 Gixxers used the 18" wheel. The '88s on used the 17" wheels. The 17" wheel and brakes will probably still work even if it is a pre '88 front end.

 

[Gerry]

The '86 and '87 Gixxers used the 18" wheel. The '88s on used the 17" wheels. The 17" wheel and brakes will probably still work even if it is a pre '88 front end.

Thanks Billy that is great info. When you talk I listen, I've read a lot of your posts and your knowledge is unbelievable. Us common folk appreciate it .
Also I was wondering about your thoughts on using an inverted front end and the stress it would put on the frame because of it's stiffness. Would the bumps in the road transfer into the frame and cause damage (stress cracks)?
Gerry

 

[Anonymous]

I'm in the process of putting 93 gsxr1100 forks on my 80 gs1100 right now. Frame stress is not be a factor. The length of the front end might be. I'm fitting parts now and still don't have the swingarm worked out yet, but I am making progress.

My present idea for the swingarm is a 2001 gsxr750 unit. It will have to be modified a bit I know - but I have some thoughts on that. I'm waiting on dimensions from the seller right now. I can go with either the stock monoshock and build the mounts - gotta move the battery. OR - this is another idea - use some shocks from a zrx1200r. They are slightly longer than the '80 suzuki's and will raise the rear slightly.

For a pic of the bike now.
http://groups.msn.com/SuzukiGSGarage/yoshimurags1000article.msnw?action=ShowPhoto&PhotoID=778


One last point to make about the inverted front ends. There are two flavors of triple clamps for these units. The early models use tapered bearing that will fit your steering head. The late models do not have tapered bearings (I think they are ball).

 

[Billy Ricks]

The steering head is pretty well braced just as it is and you should be able to run any front end you want with no problem. The rear is strong enough as well unless you do very serious riding. If you go to a wide radial on the rear, which yo should do when running a radial up front, you might think about a little bracing. The general practice is to weld X-shaped bracing between the rear down tubes above the swingarm pivot and a little gusseting below the rear subframe where it attaches to the main frame. The subframe is the portion of the frame that the seat and fender attach to. Somewhere on this site I believe there is a link posted to another site on the subject.

 

[Anonymous]

Billy, not any triple tree - any set of forks - otherwise agreed.

The problem I have is that I'm trying to use the 180 from the gsxr1100. I can't do this with the stock swingarm. I'm tired of that little pussy tire I have on it now.

I know that you can get swingarms custom made for you at swingarm.com (think thats the address anyway). But I dont want to pay the $600-800 for it. I believe the gsxr swingarms will have to be shortened across the pivot bolt area by maybe 1/4 in - I may have to shorten the length overall by 1-2 inches if I want to keep the wheelbase close to stock - and the bracing will have to be modified a bit if I use outboard shocks. All should be achievable relatively easyily (said that before).

If I get this to work the way I want it to I will send out a detail explanation if it to those interested. The zrx1200r shocks may be a bit hard to find. I've got one in my garage but I don't want to pirate for this project. 8)

All said - I'm optomistic but not fully commited yet. I still have the stock parts!

 

[Anonymous]

Just a test. I said pussy last post. Just looking to see if it but in the #'s this time. If that is true I can't asy pussy cat here. Hint -> p - u - s -s - y 8O 8O

 

[Billy Ricks]

Swanny,
I've been working on a swingarm conversion of my own. Mine is grafting a '93 Gixxer banana swingarm onto an '85 GS700. I do have to get more clearance between the frame pivot points, about 1/8" on each side. I had to cut off the stock peg mounts and adapt GSXR rearsets which I've already done. The Gixxer swingarm wouldn't clear the stock peg mounts. I'll also have to weld upper and lower shock mounts to the frame. I stopped for a while on the conversion so I could ride again. About all I have to do is flycut the frame to make room for the swingarm pivot and weld up the shock mounts. I'll be using a '97 Gixxer shock.

I know people are using late model Gixxer front ends on early Gixxers. That's why I assumed they all use the same tapered bearings. I checked on Bikebandit's schematics and it shows roller bearings all the way back to the '88-'90 Gixxers, which I know is not right. I have one of those on my bike and it uses tapered bearings which were the stock item. It may well be that the bearings can be swapped on late model front ends.

 

[Anonymous]

Billy,

I've got the banana swingarm right now. I think I'll pick up the 2001 and make some comparisons. If I go with the monoshock, it probably won't make any difference which one I use. If I go with the outboard shocks the banana swingarm makes it more difficult since one side is thicker than the other.

I haven't made any precise measurements on it so far, but he banana looks to be about 3 in. or so too long. Are you gonna leave it long or shorten?

Never gave much thought to the peg mounts. Now that you mention it, I will probably have interference problems. I've got some parts lying around also - rear sets for a 93 gsxr1100. That's the reason for the mock up - to fit parts and go through the build. Then take it apart and make it pretty.

If the steering stem is the same diameter then you should be able to fit tapers on the late model inverted triples. When I bought mine I looked at the pics close to make sure they were tapered.

 

[Billy Ricks]

Swanny,
In my case the banana swingarm is only about 3/4" longer than my stock one. Is yours a 750 or 1100 swingarm? The 750 banana is shorter than the 1100.

 

[Anonymous]

Billy,

Yea, it's the 1100 unit. I just did some measurements on the old swingarm, the 1100 'banana', and received the measurements on the 2001 750 unit - so here goes.

Definitions:

A = distance side to side in the pivot bolt area w/o dust caps.
B = distance on center from the pivot bolt to the axle bolt (axle bolt close to the center of the slot).
C = distance across the inside of the axle bolt (available wheel area).

A B C
Stock 8 3/4 21 10 1/4
1100 Banana 8 15/16 23 9 7/8
2001 750 9 21 1/2 10 1/4

The differences between the banana and the 750 unit on 'A' are probably measurement errors. Same with 'C' since two different people made the measurements.

If the stock swingarm didn't taper so much toward the front I could use it and brace it. Unfortunately the 180 won't fit at the front.

That said, the 750 unit will be much closer to the length I need. Two inches extra puts the rear wheel beyond the fender. I trying to get a good look on this.

What are your plans on getting more clearance in the pivot area? Cut the swingarm a bit or take it off the chassis? You are correct in planning to get about an additional 1/8" on each side.

The pivot bolts are a different diameter also. Maybe it would be better to remove the old pivot mounts and put in some with a hole size compatable with the donor swingarm. That sounds like a project in itself however.

 

[Anonymous]

Just noticed that all the nice spaces I added to the table to make it readable did not register. It's quite a mess. Maybe this helps.

--------------------A,--------B,----------C
Stock-----------8 3/4,------21,-------10 1/4
1100 Banana--8 15/16.----23,-------9 7/8
2001 750----------9,------21 1/2,----10 1/4

 

[Billy Ricks]

Swanny,

What year is your bike? As for the pivot, what I plan on doing is cutting the extra clearance I need off the frame pivot points. I put together a tool to do the job but it is slow going. I just picked up a 3" diameter grinding stone and made a long shaft to extend through to the opposite side of the frame that I am grinding on, hope that makes sense. In other words, if I'm grinding on the right side of the frame the shaft goes all the way across to the left outside of the frame and atach the drill to that. I also keep a piece of plastic hose over the end of the stone assembly that fits inside the pivot point I'm grinding on to keep from damaging the inside bore of the pivot points. All of this makes it easier to keep the stone straight and flat against the frame. I'll use the stock pivot bolt and cut down my stock bushings the length needed for the banana swingarm. The bushings on both units have the same outer diameter so I just need to shorten the stock pieces to fit the new swingarm. At some point I hope to pick up a 750 crank and rods to install when I get around to installing a set of Cosworth pistons I've got for my bike. Then while I have the motor out of the frame I can find an easier way of cutting that 1/8" off each side of the pivot points.

23" is about what the swingarm I have measures so you may actually have the 750 swingarm. I read somewhere that the 1100 piece is longer than the 600 and 750 swingarm. I guess I'm lucky they are close to the same length as my stock swingarm. The thing I like most about the banana unit is the caliper hanger arrangement, no caliper torque arm.

 

[Anonymous]

The GS1100 is a 1980. Is your stock swingarm about 22 1/2" long? If so, it is 1 1/2" more than mine. Interesting - if you have a different year maybe they changed the dimensions. I think I'll go check the overall lenghts of the different years to see if that makes sense.

I must say that the method that you are using to cut the pivot mounts is something I didn't think of. Is actually quite good. Give me some time to see if I can shoot holes in it! :twisted:

What is the reason for not wanting the torque arm arrangement on the brakes? Will it interfere with your exhaust system?

 

[Billy Ricks]

Mine is an '85 700 and the swingarm is about 22 1/2" long. The motors on '83 up models got more compact so that allowed a longer monoshock swingarm. I guess that's why Suzuki waited to go to the Full-Floater rear. They needed the extra room without having to make the bikes a mile long.

No particular reason for liking the caliper hanger arrangement. It slides with the wheel on chain adjustment and eliminates the torque arm. The banana swingarm also allows me to tuck the exhaust in closer to the frame. I'm actually running a stainless Yosh Duplex with an RS3 carbon canister that came off of what I believe was about a '91 or '92 GSX-R750. It bolted right up. It has exhaust spigots and the header is held on with springs. It's also super light. It's pretty snug under the motor so I wrapped the collector with some sisal I had lying around. Sisal is a flame retardant cactus fiber that I've installed quite a few times in Mormon churches I've worked on. It helps keep most of the heat away the oil pan.

After I adapt the swingarm I'll probably hunt down a 5.5" wheel to replace the 4.5" I have now. The 160 tire I'm running pretty much fills up the stock swingarm.

 

[Anonymous]

It's all becoming more clear to me now. I see why you are going the monoshock route with your bike. It would be a major change to go with the outboards. Just the opposite here. Besides keeping the twin shocks keeps the vintage look alive more on this bike.

My XR650 Honda has a caliper hanger for the rear brake. It is a slick arrangement, but it's a lot harder to change rear wheels with it. Lining up everything makes me nuts!

I started a post on my Suzuki earlier. I'll put info in when I have it on the swingarm. I'm taking pics as I go along, just going slow right now is all. Good luck on your project. I'm not shy about asking questions so you will probably hear back from me.

Thanks,

Steve

 

[Billy Ricks]

Steve,
Feel free to email me if there's anything I can help with. If you come up with a better way to cut that extra material off the frame let me know.

 

[Anonymous]

GSXR forks on GS 1150.

GSXR forks on GS 1150.

I think I made a mistake already, the forks are off a 86 to 88 gsxr 1100 and I think they had a 18'' front wheel and I wanted 17" all around. I'm not sure but if this is true than it will be interesting putting the brakes on the forks. I don't have the wheel or the rotors yet and I got 89 gsxr 1100 calipers. Guess I'll wait tell the stuff gets here and get the tape out.

*** Hi, I`m working on it just now. My problem is even more interesting, because I used Katana 600 / 750 wheels ( 3.00 x 17 front and 3.50 x 17 rear) with 87 gsxr 1100 front. My point was to get 17`` rubber without changing a swingarm. I like original GS 1150 rear suspension very much and didnt want to mess with it. I wanted to use my Bandit 1.2 Nissin 4pots calipers, identical ( I belive) to yours 89 gsxr.
To make a long story short - nothing fits.
I mean this front will fit the frame no problem, but this is it.
You can make a situation much easier buying 3.50 x 17 gsxr wheel - standart on it from 88. It will still need same playing with the axle and speedo drive ( they changed - 87 and 88 version has diffrent front forks).
You will need gsxr front fender too - 1150 does not fit.
Buying 3.50 gsxr wheel eliminates one of my problems - rotors not fiting gsxr calipers, because Katana hub is 10mm slimmer then gsxr.
Still, your calipers will not fit this front forks sliders - their tabs are made for 8 mm bolts, not 10 mm and distance between mounting holes differs 5 mm. Tabs themselves are much smaller then gs 1150 tabs, and slotting them to accept this calipers is not an option, I`m afraid.
The proper cours of action in our case is to buy COMPLETE front end from 88 / 89 GSXR - unfortunatly very rare on the market, and adapt it to our 1150 in maybe 1 hour - only `difficult` part is fitting a new handlebar.
I wasn`t patient enough to wait for it, and am going to pay for all the brackets necessary to make my setup work.
Regards - Adam M.