Swingingarm play

[Bojer]

Anyone else have more sideways play in their swingingarm than they would like ?

Even with mine done up FT there is still a mm or more of play at the wheel spindle end of the swingingarm .

I took it all apart and it seems to me the the spacer is undersize for the needle roller bearing - might just try blindly buying a replacement and hope it bigger or get it plated and ground to size ?

 

[firebane]

Brass bushings if your concerned about the play.

 

[Bojer]

Suppose I could make/get made some replacement bushes but the needle rollers should be better really - have ordered a new spacer and will measure that up to see if its any bigger and go from there .

 

[xb33bsa]

Suppose I could make/get made some replacement bushes but the needle rollers should be better really - have ordered a new spacer and will measure that up to see if its any bigger and go from there .

the needle rollers are far superior
were they rusty ?
if so you will want to replace needle/roller assembly as well

 

[Bojer]

the needle rollers are far superior
were they rusty ?
if so you will want to replace needle/roller assembly as well

No they were like it from new - checking the spacer in the bearing I have quite a lot of "slop" - hope mine is an undersized spacer and the replacement I have ordered will be better . If its not better with the new one I'll either use it as a pattern to turn up a replacement or maybe get it hard chromed and ground to size . First off I thought it was just end to end play and shimmed it up but when that didn't work I checked the spacer fit in the bearing which has too much clearance IMO -22mm nominal diameter I think - didn't measure mine at the time .

 

[teazer]

IS it side play that can be shimmed out or play in the bushes? Most swingarms are designed to have thin steel shims in one end cap to take up any side to side play at the pivot.

 

[jpmobius]

+1 teazer. Sounds like you have a newer roller bearing setup. Either way there should be zero play either laterally (i.e. as you describe) or axially ( i.e. swing arm has extra space between the two sides of the frame.) Since you are checking at the rear axle, sounds like you have the former. Seems like a lot of folks don't totally understand how the assembly is supposed to work, so for what it's worth, the most important thing to realize is that for the vast majority of bikes, the swing arm pivot bolt is drawn tight, clamping all the inner bearing components tightly between the two sides of the frame, and essentially becoming a solid frame component. The swingarm assembly "floats" on this, and how much lost motion exists depends on how closely it fits. Older bikes with plastic or bronze (etc.) bushings have the outer bushings pressed into the swingarm, and all the lateral "play" depends on how well these bushings fit on the inner bushings , usually hardened steel, clamped by the bolt. End play depends on getting the exact thickness of shimming as teazer mentioned. Roller setups are similar, but end play is sometimes controlled by the drive side bearing instead of shims. If nothing is actually damaged, as in the fit for either the outer or inner races, simply replacing the bearings should restore the assembly to new. Shimmed assemblies are another story. It is a cut-and-try process and you have to either have an assortment of shims or luck and sometimes quite a bit of perseverance to really get a close fit. Regardless, the important thing to realize is that the inner components do not spin on the swingarm bolt, but are clamped down and held fast so there is no motion between them. All the motion is between bushings or rolling elements, which restricts wear to the replaceable bushings or bearings. As long as this is the case, there should never be any wear on the swingarm, the frame or the pivot bolt, and the system should be infinitely renewable. I am assuming the "spacer" you describe is actually the inner race for the needle bearing. If so, likely you need to replace the bearings as a set to maintain the right fit. In any case, making one yourself seems like the hard way, as it will have to be frightfully hard (like the rest of the bearing) to not get instantly chewed by the needles!

 

[teazer]

And you can probably use HK2030 or a pair of 2020s each side and cut the stock bushes down to work as thrust washers. That's what we do. Needle rollers run fine on (good) stock inner bushes (spacers)

 

[Bojer]

Thanks for the reply - I fully understand how the bearings should work and my first try was to shim the ends of the spacer/inner race as I also thought end play was the likely culprit here but it seems to be the inner race/spacer is simply under size for the needle roller bearing That was after I had also tried just tightening the bolt to FT

If no one else has the same problem I am hoping my replacement spacer will sort the problem - I should have measured the original diameter when I had it apart . Although the bike has done very few miles there was perceptible radial play in the bearing/spacer that will be magnified by the swingingarm length . Don't forget its Chinese so its not a wear problem but a manufacturing issue I believe.

Will report back how things go .

 

[stroker crazy]

I guess by now everyone will have been out in the garage or wherever to check their swingarms!

Mine seems OK luckily.

Crazy

 

[Bojer]

I guess by now everyone will have been out in the garage or wherever to check their swingarms!

Mine seems OK luckily.

Crazy

That encourages me that my replacement might sort it ! - thanks Crazy .

 

[teazer]

You are probably right about manufacturing tolerances. Hope the replacement sleeves work.

 

[Bojer]

You are probably right about manufacturing tolerances. Hope the replacement sleeves work.

Me too ! At this point I'm guessing its the spacer/inner race that's the problem as more likely than the bearings themselves - of course if I had measured it at the time I would know ........... : Being Chinese made adds that extra bit of excitement

 

[Bojer]

Digging around in my garage turned up a GS500 swingingarm that seems to have a 22mm od spacer................. should have looked before ordering the new one - never mind will get the micrometer out and compare the sizes when I get it .