1991 750M Rear Wheel Spacer Issue

[ChrisR1]

OK guys have an odd issue I need help with as has me stumped.

I am fully rebuilding a 91 GSXR750M I picked up as a rolling chassis and in various pieces. During the rebuild I realised the left hand rear wheel spacer was not per the parts diagram (no idea what it is from), and so I got the original one and fitted it. Thing is that has resulted in the sprocket nuts just hitting the swingarm as the wheel rotates (which I guess is why someone had put the wrong one in there before - to get the clearance).

Thing is I can't work out why? The right hand side spacer and rear brake bracket are correct. I thought maybe for some reason the sprocket carrier bearing well had been made deeper due to wear by a seized bearing (as the seat shows some scarring), moving the bearing - and so spacer - closer to the wheel centre, but measuring a good one shows it is fine.

Anyone have any idea?? I am thinking of just getting a LHS spacer made up to match the OEM one but with an additional 5mm width to provide the clearance. Seems easiest as long as it doesn't mess with the front sprocket alignment too much

Pictures of what was fitted (the flared head)the OEM spacer and clearance with the OEM spacer fitted as attached.

[Captain Chaos]

Welcome to OSS. 

Take some time to introduce yourself in general chat section, with some pics of your 750M. We like pics. 
 

[colinworth79]

The space in the top pic is for the brake side. To go between the caliper hanger and wheel .

[martyngsxr]

i agree with the spacer is the brake side also what i have found is i had a spare rear sprocket carrier that i serviced with new bearings and such when i fitted it i found the sprocket bolts touched the swingarm when i compared the bolts side by side they were roughly 3 - 5 mm difference in lengths 

[ChrisR1]

18 hours ago, martyngsxr said:

i agree with the spacer is the brake side also what i have found is i had a spare rear sprocket carrier that i serviced with new bearings and such when i fitted it i found the sprocket bolts touched the swingarm when i compared the bolts side by side they were roughly 3 - 5 mm difference in lengths 

Thanks for that - I hadn't considered that the sprocket bolts could be longer than standard. I'll grab a new set and check them out against what is fitted. Cheers.

On the top picture this is not the RHS spacer that sits between the bearing and brake caliper bracket. This spacer has a larger mushroom head that covers the whole bearing and has a pressed metal piece rather than being from a single piece of alloy - per attached images. I have no idea what the spacer in that first image is or where it came from! Best guess is some previous owner stuck it in the LHS to get the clearance they needed.

[ChrisR1]

19 hours ago, colinworth79 said:

The space in the top pic is for the brake side. To go between the caliper hanger and wheel .

Hey colinworth79 thanks for replying. Per my other reply it isn't the same - I have no idea where it is from originally!

[ChrisR1]

22 hours ago, Captain Chaos said:

Welcome to OSS. 

Take some time to introduce yourself in general chat section, with some pics of your 750M. We like pics. 
 

Thanks for the welcome . Will do so for sure.

[SiBag]

@ChrisR1looking at your introduction post in general chat, they don't look like slingshot wheels to me. The slingshot wheels have curved spokes, yours are possibly blandit wheels etc..

This may explain the sprocket clearance issue.

Edited November 18, 2020 by SiBag

[Lachie04]

I have a spacer as per this pic I don't exactly know what it is but came with the wheel which was off a bit of a bitza if it's not there the bolts will hit the arm.

Maybe the PO made it for the same sort of reason.

 

Is it a six bolt or five bolt hub that might narrow it down?

 

Edited November 18, 2020 by Lachie04

[Dezza]

If the source model(s) for all of the bits, i.e. wheel, swingarm, sprocket carrier, and spacers cannot be identified and may be several different models, wouldn't it be best to make sure the wheel sits in the correct place in the swingarm for correct wheel alignment and then go from there? Otherwise, chopping and changing spacers/sprocket bolts etc. may enable correct wheel fitting in the swingarm but there would be no guarantee that the wheels are in line. Or am I missing something here?

[Magoo]

I have bandit wheels in my 1100l. I used the bandit RHS spacer and the slingshot LHS spacer and the rear lines up nicely (sprocket bolts are very close to swingarm but not contacting.)

...with bandit caliper hanger

Edited November 18, 2020 by Magoo
caliper hangar comment

[ChrisR1]

On 11/18/2020 at 5:51 PM, SiBag said:

@ChrisR1looking at your introduction post in general chat, they don't look like slingshot wheels to me. The slingshot wheels have curved spokes, yours are possibly blandit wheels etc..

This may explain the sprocket clearance issue.

Thanks for that insight - I'll check and see if that's possible. The other rear wheel components (sprocket carrier drum, RHS spacer, caliper hanger) are all exactly as per the M parts manual and images so all looks right in the department. Will check to see what part numbers are used with the Bandit wheels.

[ChrisR1]

20 hours ago, Dezza said:

If the source model(s) for all of the bits, i.e. wheel, swingarm, sprocket carrier, and spacers cannot be identified and may be several different models, wouldn't it be best to make sure the wheel sits in the correct place in the swingarm for correct wheel alignment and then go from there? Otherwise, chopping and changing spacers/sprocket bolts etc. may enable correct wheel fitting in the swingarm but there would be no guarantee that the wheels are in line. Or am I missing something here?

It is something I had considered but with engine out I can't check alignment along chain to front sprocket right now. I know from other comments that their is not typically a lot of clearance as stock - and given the other components (sprocket drum, RHS space and caliper hanger) all seem to be correct for the model then if I get the spacing on the LHS right I am hoping all will be good!

[colinworth79]

On 11/18/2020 at 4:07 AM, ChrisR1 said:

Hey colinworth79 thanks for replying. Per my other reply it isn't the same - I have no idea where it is from originally!

Yes your correct , that spacer is 1200 bandit .  If you need I can post some pics from my 750 L ?

 

[ChrisR1]

On 11/20/2020 at 8:52 AM, colinworth79 said:

Yes your correct , that spacer is 1200 bandit .  If you need I can post some pics from my 750 L ?

 

Sorry I didn't see your response earlier! If you are able to provide me a couple of images from your L of the left side spacer/clearance and right side spacers, brake caliper bracket I'd be really appreciative!

[ChrisR1]

On 11/18/2020 at 5:51 PM, SiBag said:

@ChrisR1looking at your introduction post in general chat, they don't look like slingshot wheels to me. The slingshot wheels have curved spokes, yours are possibly blandit wheels etc..

This may explain the sprocket clearance issue.

I think you may be right here so I am trying to understand what other things need to be accounted for in a bandit wheel swap. Do you have any idea of what haas t be done to make the swap as I can't find much in the way of info on it?

[ChrisR1]

On 11/19/2020 at 1:41 AM, Magoo said:

I have bandit wheels in my 1100l. I used the bandit RHS spacer and the slingshot LHS spacer and the rear lines up nicely (sprocket bolts are very close to swingarm but not contacting.)

...with bandit caliper hanger

Thanks for this. Can you tell me what year model Bandit it came from? And did you use the GSXR sprocket carrier? Assume the bandit caliper hanger is needed to get the disc spacing in the caliper correct?

[Magoo]

The wheels are from a mk2 bandit 1200 (though I don't think there's any difference between mk1 and mk2 wheels besides the spoke pattern)

The slingshot has a quite large spacer on the caliper side that covers the bearings whereas the bandit has a top hat spacer that fits inside the bearing seal (slingshot doesn't have a bearing seal). The difference between these spacers' widths appears to be the same as the difference in caliper hanger width on the spindle.

Bandit - narrow spacer & wide caliper hanger : Slingshot - wide spacer & narrow caliper hanger

I think my sprocket carrier is the stock gsxr one, though it was ages ago when I fitted it and I may be mistaken (as for the spacer inside the sprocket carrier, I have no clue which is in there but it fits well (It's either a B12 or a 1100L)

Disclaimer : My gsxr was a 26 years old bitsa when I got it and what I think was standard fit may not be. My swingarm is a metmachex but I'm assuming that the rear spindle width would be the same as a stock one

[colinworth79]

@ChrisR1 pics attached .

Left hand side and right hand side of the 1990 750 L I have .

Also included pic of a gsxr slingshot wheel and a bandit 12 wheel as you can see the difference on the disc side .

99% sure the sprocket carriers are the same . The wheels are same sprocket side .

Last pic the spacers -

Sprocket carrier side  @ 16.5mm

Disc side @ 21mm

Caliper hanger @ 29mm

You can fit bandit 12 wheels in a slingshot but its bit of massin about as the caliper hanger pivots around the bush in the centre .

[ChrisR1]

On 12/4/2020 at 6:58 PM, Magoo said:

The wheels are from a mk2 bandit 1200 (though I don't think there's any difference between mk1 and mk2 wheels besides the spoke pattern)

The slingshot has a quite large spacer on the caliper side that covers the bearings whereas the bandit has a top hat spacer that fits inside the bearing seal (slingshot doesn't have a bearing seal). The difference between these spacers' widths appears to be the same as the difference in caliper hanger width on the spindle.

Bandit - narrow spacer & wide caliper hanger : Slingshot - wide spacer & narrow caliper hanger

I think my sprocket carrier is the stock gsxr one, though it was ages ago when I fitted it and I may be mistaken (as for the spacer inside the sprocket carrier, I have no clue which is in there but it fits well (It's either a B12 or a 1100L)

Disclaimer : My gsxr was a 26 years old bitsa when I got it and what I think was standard fit may not be. My swingarm is a metmachex but I'm assuming that the rear spindle width would be the same as a stock one

This is great! Thanks.

Given the rear I have has the bearing seal this confirms to me that it is a Bandit wheel and that the spacer in the first image at the start of the thread I posted is the 'top hat' type you are referring to that fits inside the bearing seal. The first image in my second post would be the Sider slingshot one that has a mushroom head to cover the bearing. I suspect someone has mixed and matched just to get the wheels in (and given how it was when I bought it I have no idea if it was ever ridden like this - maybe it was just done to allow the chassis to be rolled around!)

With the narrow top hat spacer in place the main issue now is that the clearance on the disc side is too great - almost certainly because the caliper hanger is the say what now!? one and is too narrow. Looks like I need to get a bandit caliper hanger.

Or find an original swept design wheel set and get rid of these ones completely!!

[ChrisR1]

On 12/5/2020 at 2:57 AM, colinworth79 said:

@ChrisR1 pics attached .

Left hand side and right hand side of the 1990 750 L I have .

Also included pic of a gsxr slingshot wheel and a bandit 12 wheel as you can see the difference on the disc side .

99% sure the sprocket carriers are the same . The wheels are same sprocket side .

Last pic the spacers -

Sprocket carrier side  @ 16.5mm

Disc side @ 21mm

Caliper hanger @ 29mm

You can fit bandit 12 wheels in a slingshot but its bit of massin about as the caliper hanger pivots around the bush in the centre .

Thanks for taking the time to share this. That last image is the standard L model set of sprocket side spacer, disc spacer and sprocket carrier??

From the info all you guys have kindly shared I'm pretty much certain I have Bandit wheels fitted. The front seems fine as looks to be a bolt-in fitment with the Slingshot speedo drive on the LHS and RHS axle spacer (although from what I can tell the bandit discs are 19.5mm offset vs GSXR 22.5mm so that makes fitting the original slotted discs an issue....).

The rear seems to be a mix and match but I think I've got it worked out to the point that all I need is the Bandit rear caliper hanger and it should all pretty much be sorted!

Or as noted just find original wheels to get me past this shit and keep it nice and original as I want anyway!

Thanks again.

[colinworth79]

Yes you are  correct the front discs are different off set , you will either need to space the discs out or gsxr ones .

Pic of the spacers are all OE standard ones .

If running a bandit caliper hanger you wont be able to run the stock torque arm to the frame as the slingshot caliper hanger pivots and has a brass bush in .

[ChrisR1]

12 hours ago, colinworth79 said:

Yes you are  correct the front discs are different off set , you will either need to space the discs out or gsxr ones .

Pic of the spacers are all OE standard ones .

If running a bandit caliper hanger you wont be able to run the stock torque arm to the frame as the slingshot caliper hanger pivots and has a brass bush in .

Again thanks. Although on the rear brake torque arm - if you can't use the Slingshot one what do you do? I can see that the stock one I have has the brass bush, but the parts diagram for the Bandit shows it too uses a torque arm to the rear caliper. So not sure why the Bandit one can't be dropped in with the say what now!? arm?

[TonyGee]

the bandit torque arm bolts to the swingarm so theirs no movement. 

[ChrisR1]

53 minutes ago, ChrisR1 said:

Again thanks. Although on the rear brake torque arm - if you can't use the Slingshot one what do you do? I can see that the stock one I have has the brass bush, but the parts diagram for the Bandit shows it too uses a torque arm to the rear caliper. So not sure why the Bandit one can't be dropped in with the say what now!? arm?

OK I think autocorrect got that last part! It should say 'not sure why the Bandit one can't be dropped in with the Slingshot arm?'