5/8" Front sprocket spacer

[liloaty]

So I've read Katman's site and a few of the other threads on here and I still have a couple questions (I've tried to get a hold of Katman to see if he has anymore Bandit swing arms available and to ask some ?'s but I can't seem to reach him). Anyways...if I was to switch to a Bandit swing arm, is a 5.5" wheel still the largest I can go to without modifying the frame? Also, if I switch to the Bandit swing arm, I'm assuming I need to still get a 5/8" spacer correct?

My question about the spacer is this...why are people spending $50-$60 on a special sprocket instead of just cramming 5/8" of washers or something similar behind the front sprocket??

[80GS1000]

You can't put 5/8" worth of washers/spacers behind the front sprocket because if you did, you wouldn't be able to bolt on the front sprocket and there wouldn't be enough spline to securely attach the sprocket to the countershaft. I went down that route before ponying up for the offset front sprocket.

[liloaty]

Fair enough, I guess I'll just CNC machine my own when I get some free time in the lab

[Kris V]

If you do a 5/8 sprocket make sure you have enough clearance for the chain to get buy the frame. I know this for a fact that a GS1150 has enough clearance but a GS1100e does not. If you make one make it only 3/8". In the picture you will see a 3/8 sprocket and it "JUST" makes it.

[liloaty]

How will a 3/8" work?? Won't the sprockets be misaligned? It seems there are a few people on this board who got the 5/8's to work?

[Kris V]

First of all,what kind of bike is it? When doing a extended sprocket it should be supported with a out board bearing due to the stress of extension. Are you putting on a wider tire or swingarm or both?

[liloaty]

1980 GS1100e...looking into a Bandit swing arm, but I'm not sure I can afford it at the moment, so possibly just a 90's GSXR wheel.

[Kris V]

The big thing about the sprocket spacing is tire clearance. I have had chains that were not totally aligned and they worked fine. The tire and the frame are crucial for spacing. Kosman use to make an outboard bearing assy and they were and still are the best I have seen but good luck trying to find one. I think Schnitz makes one or carries one. Gixxer rims are pretty wide and the 90 model is around 5 to 5.5 in where your 80 GS is 3.75"

[liloaty]

I understand your concern with the outboard bearing, but I find it to be overkill in such a situation. When you take into consideration that you're only extending the sprocket by 5/8" and the relatively low amount of power that my bike makes in comparison to modern sport bikes, I don't think the sprocket is at any risk for failing or fatiguing enough to cause any damage.

[Kris V]

It is not the sprocket that your trying to strengthen it is the output shaft...

[liloaty]

Again, with the amount of power that is being transmitted to the shaft, do you really think there is a risk of failure by moving the force point 5/8" outward? I can see the necessity if this were a drag bike, but for street riding I really can't believe it would be necessary

[Kris V]

It`s your bike ...I say no more.

[liloaty]

Sorry if I came off as insulting, I'm genuinely asking if you think it's necessary. To be honest, you are the first person to suggest and outboard bearing for such a conversion...there are few people in the process right now and no one has said a word. Maybe you know something they dont?

[isleoman]

I'm running a katman inspired 98 bandit 1100 swingarm with a 3/8" pfm front sproket (no outboard bearing) and a 160 wide RF900 rear tire with a GS1100 rear sprocket carrier. My bike is pushing about 120 hp. If you don't do radical burn outs 3/8 is just a few milimeters more than the stock spacer and should handle the loads on the street. I've put 3500 miles on my set up since conversion.

WHY did I go this way? Cause I didn't want to have to grind my frame away to stop my 530 chain from rubbing against it. If you want great handling, the 160 wide radial tire selection is the same as the 180s. If your hung up on seeing a wide tire in the back then be prepared for other complications. Read this thread if you haven't already http://www.thegsresources.com/_forum...d.php?t=115688

You only need the 5/8 sproket to clear the width of the 180 tire.

[RJ]

I cleared a 180 tire by shimming the front sprocket (530 chain, GS1100 swingarm) with washers. I have full contact with the output shaft splines. I did have to grind the inside of the frame about 1/8" but it was at the passenger peg boss where the frame is extra thick so no compromise with frame strength. I used the GS sprocket carrier and have perfect chain alignment. No doubt you could use a 160 tire like isleoman's setup (great looking bike btw!) but the wheel I bought came with the wider tire. My setup sort of evolved over time so I didin't have an offset front sprocket when I converted over to a 530 chain, as I didn't have the GSXR wheel in mind at the time (i.e. I was too cheap to replace the almost brand new front sprocket). If you're starting from scratch an offset sprocket is probably the way to go, but you can safely shim the if the situation calls for it.