GS1150 wheel on GS1000

[GSexpress]

I thought about this offset issue a little more today and I found a quick and (potentially) dirty way to find out if your "new" wheel is offset or not
It must be done with the wheel tight but not necessarily in it's swingarm.
You take your micrometer and you measure the distance from the outside of the chain sprocket to the seam of the rear wheel.
If the distance is the same for your two wheels there is no offset.
If there is a difference, obviously there is an offset that is equal to the difference between your two measurements.
Before anyone starts yelling, make sure you are using the same sprocket hub carrier for both measurements.
I did not because I know there are the same on both bikes I measured but I also paid attention to an eventual difference in width of the sprocket itself.
Now the data: The black 2.5" wheel is on my 1100 Kat : 93 mm
The gold 3" wheel is on my GS 1000 ST: 97.5 mm
So clearly if my original wheel was centered, I need to move my new "gold" wheel to the left by 97.5-93= 4.5 mm.
And that's exactly what I did by shortening the LH spacer by 4 mm!
No rocket science here

The critical part of your suggested measurement is in your own data. Earlier you gave a measurement of 47.5 mm for the carier spacer. Now you show 46.5 mm for a carrier spacer. This spacer may not, and is probably not, the same from wheel size to wheel size due to the offset differences we are finding in this thread. Therefore useing the same carrier and spacer between the 2 wheels could add some inacuracy. You would need the original carrier spacer from each wheel and then use the same carrier to make that measurement. This also assumes that the casting ridge on all wheels are at the center of the wheel, and the same thickness. Those two you show probably are, but others, mostly later wheels may not. The other problem here is that most people only have the replacement wheel and none of the spacers, carriers, ect. that came with the replacemant wheel. Wheel center remains the only constant that you can trust and measuring from there as I have shown is the only way to be sure. It's up to you to decide how acurate you want to be and do what it takes to get there. Is a mm or 2 error a problem? probably not. But I've always been of the school that a job worth doing, is worth doing right. John, I know your trying to do it right. I;m not picking on you, I'm trying to help. I have done this stuff many times in the past. I don't have any extra wheels and parts to redo my past findings for you or I would do a pictorial as you are doing.

Maybe if I explain why you eliminate some things it will help.

The spacers between the swingarm and the sprocket carrier maintains the alignment of the chain. You don't want to change that. The spacer and caliper carrier maintain the alignment of the disc and caliper. You don't wanto chang that. With a wheel swap you just want to account for the difference in wheels. The bearing placement and in some cases (not applicable here) the disc mount spacing. You want to use the measuring formula in my previous post to find those differences. If the disc is off after that then to maintain wheel center You have to modify the disc mount to allign it with the caliper. Add a spacer under the disc, remove material from the wheel, find another disc with the right offset. Moving the caliper and modifying the brke stay is also an option as long as the wheel center is maintained.

[salty_monk]

John,

Measured my original 1000 wheel today on the bike. Measures 89mm with a 630 sprocket that is 7.33mm thick.

I don't trust this method particularly.

I tried it with other wheels and spare spacer but it wa hard to get reliable figure without it all being clamped down.

The 1150 wheel measured at 90.33 -91mm depending on where I measured it but it was using a 520 sprocket which is about 2mm less thick than the 630. Add that 2mm and I'm at 93mm the same as your 1100 wheel.

I have some pics I will post: Red is 1150

750 sprocket drive spacer

[salty_monk]

This next post shows that I definitely need to move the wheel to the brake side. I put a spacer underneath and it come out to roughly what i measured with CAD.

The hub lip to bearing face measurement on both wheels is 12.5mm
This means we can use the hub lip as a solid point in a comparative measurement.
Bear in mind this is on garage floor not a flat table but you'll see what I'm getting at.


With wheels drive side down like this if the rims were offset the same then the 2.5" rim should sit right inside the beads of the 3.5" rim equidistant. It doesn't.



You can see there is a big gap at the bottom.



No gap at the top





To make them match I had to put about 2.5mm under the 1150 wheel. (same as putting 2.5mm on the face of the bearing on drive side) This approx matches the CAD too.

Hope this is helpful John. Best I could do tonight.

[salty_monk]

John,

Best I can see my spacers match yours. I didn't get the measurements for the left side or right side spacers that touch the bearings yet.

Dan

[John Kat]

Not yet John, still early here, you're 9hrs ahead of me

By the way - thinking about this, are we 100% that the seam is central/in the same spot on the wheels in relation to the rim? It would seem to make sense that it is central but tool offset in the casting might be different wheel to wheel...

If I have to I will pull my rear 78 1000 wheel & spacer set to measure. By the way, what sprockets are you using? 630? 9mm thickness?

Where are you in France? I lived just outside Hyeres in the South for a few months.

Dan

Hi Dan,
Yes, 9 mm sprockets on both.
On the Kat I have a 530 chain and on the Gs 1000 a 630.
I don't known Hyeres well but I must have driven by on the route to Saint Tropez
Since I took early retirement I live in the South West of France close to Bergerac.
I used to come to California often in my HP days....
One of the best moments was when a colleague lent me his bike and I drove down from Santa Clara down to Big Sur along the coast.
I stopped by at Laguna Seca of course.

[John Kat]

This next post shows that I definitely need to move the wheel to the brake side. I put a spacer underneath and it come out to roughly what i measured with CAD.

The hub lip to bearing face measurement on both wheels is 12.5mm
This means we can use the hub lip as a solid point in a comparative measurement.

Dan,
I can't argue these facts.
What's amazing is that I'm 99.99% sure that my offset is the other way round
What is clear is that my GS 1000 ST wheel ( 18*2.15) is different from your 17*2.5.
The B to B is 111 mm, the bearing recess on the brake side is 5 mm and 10 mm on the drive side.
The "sprocket offset" measurement is ....93 mm.
Not comparing the same wheels should explain why we don't get the same results.
If you pull your other GS 1000 wheel out, I will pull my 1150 wheel out to!
I enjoy the discussion

[John Kat]

Measured my original 1000 wheel today on the bike. Measures 89mm with a 630 sprocket that is 7.33mm thick.

I don't trust this method particularly.

I tried it with other wheels and spare spacer but it wa hard to get reliable figure without it all being clamped down.

The 1150 wheel measured at 90.33 -91mm depending on where I measured it but it was using a 520 sprocket which is about 2mm less thick than the 630. Add that 2mm and I'm at 93mm the same as your 1100 wheel.

You seem to be measuring to the edge of the ridge while I'm measuring to the middle?
This would account for another 3 mm approximately I believe.
Another check with the wheels tight could help?

[John Kat]

This where I got to today too. All the previous pages making sense but trying to make it fit what I have (I'm going the other way) was making my head spin.
I need to move the wheel 2.25mm to the left but keep the drive line the same, ie narrow the chain/tyre gap.
I was about to skim a spare sprocket carrier and take the same off the carrier spacer. But having second thoughts I'll use the offset sprocket I have.
I will not have to kink the torque arm and the standard chain guard will fit perfectly.

Tatu,
You seem to be in agreement with the measurements I made i.e. the 1150 wheel needs to be moved to the left to remain centered.
I know this will create an offset issue with the front sprocket.
What I did, is insert a small spacer behind the front sprocket as there is ample room to do that.
Would you be so kind and measure your GS 1000 wheel.
We need the Bearing to Bearing distance,the bearing recess on both sides and if possible the offset from the wheel center to the LH bearing flange.
Thanks
John

[John Kat]

GSexpress,
I've read carefully through your comments.

The critical part of your suggested measurement is in your own data. Earlier you gave a measurement of 47.5 mm for the carier spacer. Now you show 46.5 mm for a carrier spacer.

My mistake it's 47.5 mm

This spacer may not, and is probably not, the same from wheel size to wheel size due to the offset differences we are finding in this thread. Therefore useing the same carrier and spacer between the 2 wheels could add some inacuracy.

Maybe but I checked the P/N and the GS 1000/1100 use the same sprocket carrier as the 1150.

You would need the original carrier spacer from each wheel and then use the same carrier to make that measurement.

Not if I want to compare the two wheels directly.

The spacers between the swingarm and the sprocket carrier maintains the alignment of the chain. You don't want to change that.

Well, clearly you want to keep the chain aligned if at all possible BUT if the wheel needs to be moved to the left you will have to shorten the LH spacer. The chain is now out of line and you will need to offset the front sprocket by the same amount to correct this.
My current thinking on this whole issue is that we are not comparing the same wheels as I mentionned to Salty Monk.

[tatu]

Tatu,
You seem to be in agreement with the measurements I made i.e. the 1150 wheel needs to be moved to the left to remain centered.
I know this will create an offset issue with the front sprocket.
What I did, is insert a small spacer behind the front sprocket as there is ample room to do that.
Would you be so kind and measure your GS 1000 wheel.
We need the Bearing to Bearing distance,the bearing recess on both sides and if possible the offset from the wheel center to the LH bearing flange.
Thanks
John

Bearing to bearing - 116mm
left recess - 12.5mm
right recess - 5.0mm
From the left inside chain adjuster 123mm plus the thickness'v my straight edge = 124mm
But I clamped a 1000 swing arm to my bench and was supprised by the result which may still be different from yours.

My ally wheels came from an EFE 1100 and the rear bolted straight in as standard. This has a bearing to bearing space of 116mm ,outside faces

My wire wheel hub is from an early GS 750.
This has a bearing to bearing space of 111mm,

Both wheels spacing from the drive side are correct and run the wheel bang on center leaving me to make up one spacer 5mm thicker between the caliper hanger outside and chain adjuster.
For interest, the measurement between chain adjuster and wheel center drive side is 123mm
The right side (Brake) is 121mm so a 2mm offset to the right.
I reversed the wheel in the swing arm (to highlight or eliminate any errors) and came up with exactly the same numbers.


This picture only shows that the dimentions of the original and newer ally are the same.

My jig











This is the spacer that needs to be increased by 5mm.

In my case this is a conclusive result and that is the way I'm going.
I suspect that the wire wheel is causing confusion with your measurements.

[John Kat]

Tatu,
Many thanks...
I redid a quick check using your "swingarm extension" method and guess what the GS 1100 Kat with it's original wheel is within 2mm of the center and the GS 1000 ST with the 3 inch wheel is bang on center with the LH spacer shaved by 4 mm.
I must have a very unique 3 inch wheel....
I noticed on one of your pictures that you tire just clears the brake stay.
So does mine thanks to the short LH spacer (and the corresponding spacer on the right side)
I have no idea where this wheel came from as I bought it on ebay.
What other Suzuki's used this spoke pattern except the 1150s???
Very nice your GS 1000 SN with wire wheels!

[tatu]

Tatu,
Many thanks...
I redid a quick check using your "swingarm extension" method and guess what the GS 1100 Kat with it's original wheel is within 2mm of the center and the GS 1000 ST with the 3 inch wheel is bang on center with the LH spacer shaved by 4 mm.
I must have a very unique 3 inch wheel....
I noticed on one of your pictures that you tire just clears the brake stay.
So does mine thanks to the short LH spacer (and the corresponding spacer on the right side)
I have no idea where this wheel came from as I bought it on ebay.
What other Suzuki's used this spoke pattern except the 1150s???
Very nice your GS 1000 SN with wire wheels!

You're welcome, and thanks, I have a sprocket carrier from a GSXR1100 and that moves the sprocket 3mm away from the wheel however I would like to keep everything a stock as possible so now if I need to move the chain a bit it will be a peice'v cake.

[salty_monk]

Looks like Tatu's 1000 wheel & 1100 wheel measures up same as mine! John your wheel seems to be very strange. Maybe the 3" ones are different although I think you said your 3.5" matches it...

Dan

[GSexpress]

GSexpress,
I've read carefully through your comments.
My mistake it's 47.5 mm
Maybe but I checked the P/N and the GS 1000/1100 use the same sprocket carrier as the 1150.

I was noting the spacer, not the carier.

Not if I want to compare the two wheels directly.
Well, clearly you want to keep the chain aligned if at all possible BUT if the wheel needs to be moved to the left you will have to shorten the LH spacer.

Or the sproket carrier spacer. There is room for small movement of the carrier inward before it bottoms out.

The chain is now out of line and you will need to offset the front sprocket by the same amount to correct this.
My current thinking on this whole issue is that we are not comparing the same wheels as I mentionned to Salty Monk.

My formula was not for comparing specific wheels but to mount most any similar type wheel eliminating the need for irrelivent comparisons to different swaps.

You seem to have found what will work for you. I'll bow out now. Don't need to beat a dead horse.

[John Kat]

I thank you guys for putting up with all this...
Obviously I was not happy to see that not only you guys came up with a different conclusion but also that my answer requires moving the chain to the left.
Knowing the efforts the Suzuki engineers put into standardisation to reduce costs it seems unreal the 1150 would have an offset chain compared to the 1100.
In fact there is one variable that we have neglected in our reasoning: the width of the swingarm with the wheel tightened
Let's suppose my RH spacer was too short.
When I mount the wheel it will appear shifted to the right!
To correct this, I shorten the LH spacer and lengthen the RH spacer to keep the total mounted length identical.
My wheel is now centered but....the swingarm has a greater pinch than yours.
I did a very quick check and ...yes the swingarm is definitely narrower with the 3 inch wheel.
My "as built" RH spacer measures 16 mm.
What's yours like?
I will get more data later on