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The friendly Ghost.
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13,172 Posts
Discussion Starter · #1 ·
No longer looking for this work, thank you for looking.

Can I get a mod to move this to the Suspension sub-forum, it applies a little more there.
 

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Just a bit of advice fella :)

You forgot to mention that you will need a bearing centre spacer as well, if you don't fit the GS sized spacer between the bearings you WILL bend the pivot bolt in use then its never coming out again

Another option for this spacer on some bikes is to just sleeve the spacer down I used a stock GS spacer on one of mine that as luck would have it fitted perfectly into the spacer from the arm I was using

Hope it helps
 

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Is my bike ok?
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15,025 Posts
Just a bit of advice fella :)

You forgot to mention that you will need a bearing centre spacer as well, if you don't fit the GS sized spacer between the bearings you WILL bend the pivot bolt in use then its never coming out again

Another option for this spacer on some bikes is to just sleeve the spacer down I used a stock GS spacer on one of mine that as luck would have it fitted perfectly into the spacer from the arm I was using

Hope it helps
I never considered that, but it makes perfect sense. I love the knowledge in this place.
 

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The friendly Ghost.
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13,172 Posts
Discussion Starter · #4 ·
Just a bit of advice fella :)

You forgot to mention that you will need a bearing centre spacer as well, if you don't fit the GS sized spacer between the bearings you WILL bend the pivot bolt in use then its never coming out again

Another option for this spacer on some bikes is to just sleeve the spacer down I used a stock GS spacer on one of mine that as luck would have it fitted perfectly into the spacer from the arm I was using

Hope it helps
I was going to cut the stock SV650 spacer down to width.
 

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watches you sleep.
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9,116 Posts
I was actually able to do the same thing 4cups did with the Busa swingarm swap on my 1992 GSXR 750. I was able to take the sleeves from my GSXR 750 swingarm, slip them into the busa sleeves and use the GSXR pivot bolt. There was absolutely zero play between them. I got lucky Im sure, but you never know. It might be worth it to look for sleeves from another bike. It would take some extensive googling but you could potentially end up with what you need for peanuts as opposed to having someone machine them for you. Also check McMaster Carr. They have tophat spacers. Didnt have the size I needed but they do have some. They probably dont NEED to be made of harneded steel either since they take on such an even load and dont move much. I wouldnt suggest whittling them out of wood but Im sure theres other options.
 
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I was going to cut the stock SV650 spacer down to width.
The stock SV spacer is already the right width for the arm as it just sits between the bearings to stop the centres being pushed inwards :) the problem lies with the ID its too big for the GS spindle so the spindle has room to bend far enough to stay bent then it wont easily come out again ....

...So what you need is a spacer with the ID of the GS spacer & the OD of the SV spacer :)
 

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The friendly Ghost.
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13,172 Posts
Discussion Starter · #9 ·
The stock SV spacer is already the right width for the arm as it just sits between the bearings to stop the centres being pushed inwards :) the problem lies with the ID its too big for the GS spindle so the spindle has room to bend far enough to stay bent then it wont easily come out again ....

...So what you need is a spacer with the ID of the GS spacer & the OD of the SV spacer :)
Stock SV650 center bearing spacer does not match the OD of the pivot bolt, it is larger by about a mm.

This SV650 swingarm has been narrowed to fit the frame. If the bearings are too wide, I will get new ones or if there is room, I will cut the stock spacer down in width.



I am curious about what bending forces you are talking about, I guess I am not seeing the big picture of two point loads with upwards vertical forces at 12" width about the center counteracted by two point loads with downwards vertical forces at 10" width about the center having any bend in the pivot bolt stopped by a simple bushing not supported.

I guess what I am trying to say is that the swingarm pivot bolt bearing surfaces is a tube that resists bending, the pivot bolt resists bending and as metal will spring back as long as the forces are not too great (pivot bolt having the least resistance to bending), the bearing race spacers resist bending and the needle bearings resist bending. Where is the bending that you are talking about coming from?



As a side note, I went ahead and found a 1m length of 20 mm OD x 3 mm Wall seamless steel tube and will be cutting this to width and using this as a spacer between the pivot bolt and the swingarm stuffs. It wasn't cheap and if it works as I want it to, I won't need these made. (This should mitigate any concerns about the needing a new spacer for the center of the bearings.)
 
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Ok I had not realised that the arm had been narrowed so fine you need to make or shorten & sleeve the bearing spacer just as I originally said :)

To understand why the spacer is needed you need to know it performs 2 tasks
#1 stops the centre of your bearings from being pushed towards each other & possibly collapsing
#2 supports the spindle to prevent it bending too far

This is why its there in the first place & do you really think Suzuki & every other maker would add a lump of metal if it was not needed?

I do not pretend to know what forces are exerted or in which direction but I have seen the result of the spacer being either too loose too short of missing completely to ever contemplate not fitting one that's right

So once again you need a spacer that is the same OD as the stock SV one with the ID of the GS & the correct length to fit snugly between the bearings

As an aside I once bought a gs that had been fitted with a B12 swingarm on tophats (something ive done myself dozens of times) the fool that did the work had not fitted a suitable spacer & the arm was seized almost solid + pivot bolt was bent to the point I had to cut it out as there was no way of getting it out without damaging the frame this was not the first time ive seen this & I doubt it will be the last ..... None of mine which have been done correctly have ever had a problem & we are talking upwards of 30 separate bikes here

Hope that's cleared it up Cheers :)
 
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And while I think after reading your last post again ...

As you rightly surmise the pivot bolt will bend & spring back to a certain degree (metal memory) if you overbend it it will stay just like any other piece of metal the spacer stops it being bent that far if its a reasonable fit, just like wheel bearing spacers do on the wheel spindles
 

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The friendly Ghost.
Joined
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13,172 Posts
Discussion Starter · #12 ·
Ok I had not realised that the arm had been narrowed so fine you need to make or shorten & sleeve the bearing spacer just as I originally said :)

To understand why the spacer is needed you need to know it performs 2 tasks
#1 stops the centre of your bearings from being pushed towards each other & possibly collapsing
#2 supports the spindle to prevent it bending too far

This is why its there in the first place & do you really think Suzuki & every other maker would add a lump of metal if it was not needed?

I do not pretend to know what forces are exerted or in which direction but I have seen the result of the spacer being either too loose too short of missing completely to ever contemplate not fitting one that's right

So once again you need a spacer that is the same OD as the stock SV one with the ID of the GS & the correct length to fit snugly between the bearings

As an aside I once bought a gs that had been fitted with a B12 swingarm on tophats (something ive done myself dozens of times) the fool that did the work had not fitted a suitable spacer & the arm was seized almost solid + pivot bolt was bent to the point I had to cut it out as there was no way of getting it out without damaging the frame this was not the first time ive seen this & I doubt it will be the last ..... None of mine which have been done correctly have ever had a problem & we are talking upwards of 30 separate bikes here

Hope that's cleared it up Cheers :)
And while I think after reading your last post again ...

As you rightly surmise the pivot bolt will bend & spring back to a certain degree (metal memory) if you overbend it it will stay just like any other piece of metal the spacer stops it being bent that far if its a reasonable fit, just like wheel bearing spacers do on the wheel spindles
So, you have had me thinking about this while I was working in the garage.

The stock SV650 pivot bolt is aluminium, just under 20 mm diameter. The stock SV650 bearing races are 20 mm inner diameter (some play, not much). The stock SV650 center spacer is 21 mm inner diameter (lots of play, see pictures). The stock SV650 needle bearings are a press fit into the swingarm pivot tube, they butt up against their seat machined into the pivot tube on the inner edge; their needles are a snug fit with the outer diameter of the bearing races, they don't contact any other parts.





The only parts that the center spacer is actually loaded with forces by, are the two bearing races. The two bearing races are being forced inward by the pivot bolt and need to have a solid structure to resist the compression from the bolt, i.e. the center spacer.


tl/dr version: I don't understand either of the two tasks you claimed the center spacer completes.


With the bearing spacer in the wheels with regular ball bearings (different type of bearings), it is to provide a solid object that allows compression against the two inner bearing races without putting the compression through the ball bearings. This is unlike the steering stem bearings which may also be ball bearings that do not use a spacer and instead intend for the compression to go through the ball bearings and cope using a slight offset in the races to accept axial forces.


As for the spacer work that I did...

I bought some 20 mm OD, 14 mm ID seamless tube, filed it evenly to snugly fit the top hats. I cut it to length such that it was 1 mm less than the pivot bolt top hat, center spacer, top hat width. (225 mm in case anyone was wondering what my measurement was.) I then used that length and ground down then filed the center spacer length until I could just barely fit the top hat, center spacer, top hat installed on the 20 mm OD tube between the pivot bolt bosses. I then cut and filed the swingarm mostly evenly (just a little wider on the chain side for clearance issues, no more than 1 mm off center) until I could just install the whole assembly between the pivot bolt bosses.

Now, I need to find me some narrower needle bearings...
 
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So, you have had me thinking about this while I was working in the garage.

The only parts that the center spacer is actually loaded with forces by, are the two bearing races. The two bearing races are being forced inward by the pivot bolt and need to have a solid structure to resist the compression from the bolt, i.e. the center spacer.


tl/dr version: I don't understand either of the two tasks you claimed the center spacer completes...
WHAT? .... Above you say you don't understand the function of the spacer directly after explaining one of its functions perfectly :doh:

Once again I will attempt to explain the second function then I am done with it .... The spacer also allows the spindle to flex slightly without allowing it to actually go far enough for it to bend & stay bent hence the slightly sloppy fit..... if it were a tight fit on the spindle any small mark on either or even some old dried grease or dirt could see you trying to smash the bearings out through the frame every time you tried to move the spindle... it really is as simple as that :)

Having read the whole thread again I do understand what you are trying to achieve & think it will work well enough if you can find some bearings to suit although given the problems you face I have to say its not the way I would have tackled the job in this instance

Good luck with it :)
 
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