Brake caliper piston holding tool for XJ900

I was removing the pistons from the calipers on my '83 XJ900 Seca using the compressed air method. That worked somewhat, but as they got nearer to the end, I thought about the brake fluid that would likely spray all over the shop as soon as one of them popped. Seemed like there should be a more "controlled" method.

So once again I header to CAD and modeled up these piston "brake shoes" so I could hold the piston firmly while twisting/lifting the caliper body to get them off. It worked!

You insert the two halves into the piston and tighten 3/8" bolts into the holes. (don't overtighten and bottom them out) The holes are tapered, so as the bolt goes in further, it spreads the halves like a set of little brake shoes. You can then clamp the bolts into a vice, grab ahold of the caliper body with two hands, and twist/lift the two apart. It does take quite a bit of force, and you might need to twist back and forth a little to get the seals to loosen up, but the tool showed no signs of slipping.

Model uploaded to Thingiverse at https://www.thingiverse.com/thing:6981717.

(Note: Been having trouble getting pictures to upload, not sure what's going on, but it seems to be something with the site. It just spins for a couple minutes, then the pictures disappear.)

 

Looks like it will let me upload pics with the Upload a File button. The copy/paste method still isn't working though.

Note this tool should also work for any piston with a 37mm inside diameter.