K8 GSXR wheel and 180 tire in factory swingarm!

[Darkstang]

Got an almost free 2008 GSXR 750 wheel and tire complete with all the brakes, spacers and axle. SOOOO,, off to the shop I go.

First I measured the width of the GSXR wheel combo including all spacers and compared to the stock 83 GS1100E setup. .808 to ...........810" wider. Cush drive is WAY out to the side as well. But I know it has to be made to work! $25 is hard to argue with.

Spent all last night reading thread after thread on wide tire and wheel combo. 81GS1000 did the K5 conversion so that is where I got most of my ideas.

So here is what I have done so far...
First I measured and drew out the factory setup , then the GSXR. I needed to shave the .800 off the GSXR AND get the cush drive over so I would not have a major offset front sprocket.

Chain side mods:
.200" of the GSXR outside spacer.
.200" off the cush driver spacer between the bearings.
Then turned the inside of cush drive about .100 and inside of the cush drive on the wheel about .125"

This gave me .400 on the left side.
Now I will have to shave the cush drive rubbers.
I also removed the sprocket studs and shaved the face about .070 and flipped the sprocket over. This and the spacer .200" moved my chain approximately .300" closer to the tire.

Brake side:
Removed .400" from the outboard spacer.
All I need to do now is make a brake stay or way to hold the brake.

Tomorrow I will take pics of the mods and machine work done to the cush drive hub and take better measurments. Exhausted right now.

It bolts in easily and looks like a 1/2" offset front sprocket will work. Have to align it first then check sprocket alignment.

Oh yea, the stock GSXR axle is hollow. Goint to lob the ends off a few thou shorter than the spacer/wheel combo, turn some bushings to press in the hollow shaft, then use my 83 axle....

Got to get some rest now.......
Ken

[rapidray]

Ken, just so you know, the READILY available aftermarket offset sprockets are either 3/8s or 5/8s in offset. Ray.

[Colin Green]

That is a great deal and a lot of good work.. Will be interested in seeing the photos as I will likely be having to go down the same path at some stage

[posplayr]

Ken, just so you know, the READILY available aftermarket offset sprockets are either 3/8s or 5/8s in offset. Ray.

I would think that no matter what that a 5/8 offset is going to be required. I have a 4.5" wheel with 3/8" offsetsprocket and the 530 chain just splits the distance beyween the frame and 170/60-18 tire . 5/8" seems to be standard fore a 5.5" wheel

[posplayr]

Ken, just so you know, the READILY available aftermarket offset sprockets are either 3/8s or 5/8s in offset. Ray.

I would think that no matter what that a 5/8 offset is going to be required.

[TheCafeKid]

My next hooligan bike has a 190 in the stock swinger

[Darkstang]

After I check wheel alignment and get into the chain alignment, I will have to figure out the offset and chain size. The K8 came with 525. I can find 525 and 520 rear sprockets easily. Where are you guys getting your 525 and 520 front sprockets to fit the GS. I got my 530 stuff from Z1 but they do not show anything else.

ken

[salty_monk]

I got my 520 set from Z1. There is one particular chain that is narrower than any other (the one 80GS1000 uses). The rest are all at least 2.5 - 3mm wider or more in my experience.

You may find you need that added clearance...

Dan

[Mysuzyq]

Rob (Katman) has done several 180 tire/stock arm conversions and posted info re. clearance & spacers here that probably came up in your search. Clearance varies according to the brand of 180 tire too, apparently...

http://www.thegsresources.com/_forum/showpost.php?p=732567&postcount=15

PM him, or visit his site which offers a lot of info and parts for conversions.

[Darkstang]

Back in the shop. Got the tire/wheel combo mocked up and installed 5/8" of spacers behind the counter sprocket. With the 530 chain and rear sprocket flipped, I am only a few mm from the tire but good on the frame. Might try it with the rear sprocket on normal. looks like 5/8 offset will work.

Not going to get real concerned untill I get the axle shaft made. Right now, it is just tightened down with the stock axle pulled all the way back and checked wheel alignment with two long straight edges.

Took some pics I will post up later. Probably about as far as I can go untill I finish axle shaft and get chains and sprockets ordered.

Ken

[Darkstang]

Machined sprocket face

[Darkstang]

This shot shows how deep I was able to sink the cush drive. The tab is where the lip of the wheel used to be. Machined the lip face down and deeper inside the wheel as well.

[Darkstang]

Backside of cush drive and spacer.

[Darkstang]

[Darkstang]