Swingarm top hat bushings

[2scars]

Generally speaking if you are having bushings turned up for an 18mm pivot bolt to work in a later monoshocked swing arm with a 25mm sleeve originally, what material do you have them made from?  Mild steel, or is something harder required?

 

thanks.

[coombehouse]

If you still use the original sleeves & push the top hats inside them, it doesn't matter what they are made from so aluminium would be good. If you are replacing the sleeves completely & intend the bearings to run on the new top hat, then you would need something tough & hard-wearing so a high quality steel, hardened & tempered would be suitable. Stainless wouldn't be much use as it's pretty soft.

[wraith]

I've always used Aluminium top hats, keeping the original bearings sleeves.

Then the bearing sleeve is still doing its job and the top hat is just a size reduce spacer and should not move in the swingarm once fitted and bolted up in place.

[2scars]

So I have my guy in the machine shop turning up a top hat to go into the factory hardened bushing.  When you make these type of changes do you also add a reducer for the crush sleeve inside?  I have read that the reducer will help with pivot shaft deflection...

Brandon

  

[TLRS]

That’s an interesting point.. makes sense to have a tube that won’t sag around the smaller axle. Seems reasonable it would loose some bearing sleeve clamping area.