1150EF - GSXR swap.

[Guest]

Ok. I've decided to jump in over my head and try this swap. I have acquired a 1990 GSXR 750 and I've stripped all the parts off it to try and add my name to the list of other resto - modders. I have spent what seems like countless hours going over all the posts regarding this swap and I'm hoping that the swap will go smoothly. I'm not foolish enough to believe that it will be a plug and play scenario but, nothing ventured....... Wish me luck!

[Mark1]

Here's the parts donation bike.

[Mark1]

The rear rim is 5.5 with a 170 Michelin Pilot tire. I can get it in there but need to space it for centering. I tried putting the GSXR swingarm in but there is just no way it will fit. The distance between the pivot bolt mounts are correct but the overall length is too short and it contacts the frame where it starts to flare out. I'll have to stick with the stock 1150 swingarm and space appropriately. I will still look for another swingarm (bandit/GSX 1100) in the meantime but I'm hoping I can use the stock one. As far as the inverted forks, I'm not sure about that either. The front tire will fit into the stock forks and I can make the spacers for the new calipers.

It's looking more and more like this swap is just going to be rims/tires and brakes.

As I've read a hundred times so far, any expertise from the experts would be welcomed.

[mr wu]

The front end swap is a simple bolt on....The gsxr swinger will work also..."search the forum"

If you're not inclined to use the gsxr swinger I might be interested....

[Mark1]

Thank you Mr. Wu. Believe me, I have searched the forum. That's why I thought I could take this on. I knew the forks were going to be short and reading all the threads about the swap I saw how ground clearance was going to be and issue, especially with a 4 into 1 header. I have a bottom fairing as well so I don't think that the front will work out. The 1150 will take the front wheel without too much hassle. It just looks like should have been looking for a 1200 Bandit donor bike instead of the Gixxer.

[cdnoel]

Have an 87 GSX-r 4.0 X 18 rear wheel in my 80 GS1100E. Converting to a 520 chain not only made sense for weight saving but also cost, availability, and clearance made it a no brainer. Pushed the chain closer to the frame with a 3/8 offset sprocket. These sprockets are thinner than the stock sprockets where they mount to the shaft. Bought a few extra Suzuki washers to fine tune the alignment. One of these washers is required on the outside to lock the nut but I used two more behind the sprocket to put where I wanted it. Basically achieved 1/2" offset with a 3/8 sprocket once I realized the thinner sprocket makes it more versatile than the stock one. In order for the chain to clear the rear shock I had to go with no chain guard and had a friend with a metal lathe turn a few mm off of the rear sprocket carrier. Of course the wheel was centered before I did all this work to the sprockets. Went with no spacing on the sprocket side except the one that rides in the dust seal. Had to have a custom spacer turned down by my friend on the brake side. No spacing on the sprocket side caused an issue with the sprocket bolts hitting the shock. Since the sprocket was moved in a few mm this allowed me to also have my friend turn the sprocket bolts down to clear the shock. Have a 150 on the rim now but I think I can get a 160 in this space still. Hope some of this info provided helps. Sounds like your looking to take up a bit more real estate than I did in your swing arm. Reason I went with 87 GSX-r wheels is that they look pretty much like GS1100/1150 wheels but are lighter and provide more modern availability and options for tires.

[Mark1]

Thanks cdnoel.

I found this pic on a Katana page and I'm lucky enough to know a really good aluminum welder. It won't be exactly the same as I would rather not cut all the way through the swimgarm but it should end up very similar. Just making a jig to make it all line up and swap the upper brake stay and brake line locator from the top of the swingarm to the bottom. This should allow me to use the 5.5" rim without issue and will make regular maintenance and tire swaps easier. After I get this all sorted, I'll focus more on the front end to see if it makes more sense to modify the bottom of the shocks or make spacers.

[dorkburger]

Good luck, ill be following along. I dig resto mods, snd there arent too many 1150 resto mods.
Civil rock has an 1100e with an 1150 front end with a GSXR wheel.

[cdnoel]

This swing arm mod should help with the rim and shock clearance. The frame is going to be another problem. Im not convinced i could get more rim in mine even with a moded swingarm. A 5/8 front sprocket offset may be all your gonna be able to get. After that the only place to go is outboard of the frame.

[Mark1]

This swing arm mod should help with the rim and shock clearance. The frame is going to be another problem. Im not convinced i could get more rim in mine even with a moded swingarm. A 5/8 front sprocket offset may be all your gonna be able to get. After that the only place to go is outboard of the frame.

When I threw the rim and tire on initially, I had no real issues with the frame. In fact, that is why the Gixxer swingarm wouldn't work. It was so short that it would contact the frame where it flared out for the tire and couldn't reach the pivot bolt. The 1150 swingarm is plenty long but it just wouldn't spread far enough for all the spacers and caliper mount. I described it as a tuning fork to a friend if that makes any sense.

[cdnoel]

Chain alignment is the issue that concerns me. I bet your new rear sprocket is more than 5/8" out from where it used to be. 5/8" of front sprocket movement is going to have the outside links of even a 520 chain spooky close to your frame. You may even have to shave the front sprocket cover some. I don't have the advantage of seeing your parts first hand but looking back on the road I've already been down I think you should check.

[Mark1]

I will definitely put in a lot more effort to make sure of alignment. I admit it has been a bit of a lesser concern than fitting the wheel in. This is another reason I love this forum. Guys like you helping me with their own experience! The last thing I want to do is create something dangerous or have to replace bearings every week. Cheers.

[gearhead13]

Is that the Gsxr that was on Used Victoria?
Are you using the engine?

[Mark1]

It is indeed the one that was on Used Vic. It looks like all I'll be using at this point are the wheels,brakes and axles. I figured I would put all the suspension and triple clamp together to sell as a suspension upgrade for someone. I won't be using the engine. PM me if you'd like it.

[Mark1]

No turning back now. Got the swingarm widened an inch so it will take the GSXR wheel, spacers and caliper mount. After I got all the suspension back together, I just eyed the offset for the front sprocket and I'm not too far off at all. I haven't measured it yet but it should be just a small offset.