I used the gun on the bleeder valve as well
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Brake Caliper Frozen and more
- Thread starter xs650-4-me
- Start date
I dunno, I kinda like the thrill of anticipating the “pop” When using air and I’ve gotten some pretty gnarly calipers freed up.
Trust me I tried that, as well as heat and you name it - last recourse was the grease gun - and it worked - had my doubt though
The Standard
XS650 Addict
Late to this thread but now at a point of rebuilding my front caliper. Before stuck piston removal with air or grease from gun, is it safe to assume others where trying with the caliper plier removal tool? I thought with rusty piston, if piston was sprayed with penetrating oil and this plier is used the side-to-side twisting may free the piston in its bore.
Also can anyone provide a part number and source for Ferodo Platinum organic breath pads for an XS-2 (‘72) model?
Also can anyone provide a part number and source for Ferodo Platinum organic breath pads for an XS-2 (‘72) model?
The Standard
XS650 Addict
One other item, does the front wheel have to come off to remove and reinstall the front caliper on an early model bike?
No it does not.
That probably won’t work without scoring the piston with plier marks IF you can even get it to move. Air has always worked for me and has been relatively easy.
Eotnak
XS650 Enthusiast
Let it soak in PB Blaster or transmission fluid mixed with mineral spirits overnight. Use compressed air with a wooden block to act as a stopper. I've done this hundreds of times, never a problem. I would use grease method as a last resort...not interested in cleaning that out.
Am I right in thinking that the wrench marks on the top lip of the piston might look terrible, but won't have any bad effect as they will not rub against any seal or anything?
I will try and clean up the pitting on the main body but am thinking of reusing this...
I will try and clean up the pitting on the main body but am thinking of reusing this...
If that's surface rust below the groove, it'll clean up. If it's pitting, it's scrap. In my opinion, of course.
you're right on the wrench marks,
Yeah that's pretty heavy pitting.
That pitting is right where the seal will be when you install new pads. 
Yeah that's pretty heavy pitting.
That pitting is right where the seal will be when you install new pads. Exactly.Yeah that's pretty heavy pitting.
Is that the only pitting, or is it like that all the way around?
I've used worse pistons.
Yes, the pitting is right where the seal will be with new pads. So, if you have them, use pads that are somewhat worn down.
I've used worse pistons.
Yes, the pitting is right where the seal will be with new pads. So, if you have them, use pads that are somewhat worn down.
AND soaked with brake fluid...
I got this!
full story; pads I ordered for Uly were too thick cuz it had a rotor from a different model, problem solved.
If you do replace the piston, get a stainless one. They can be had for not much more than a steel one and you won't ever have to worry about rust again.
https://www.ebay.com/itm/3715948221...lp:2332490&itmmeta=01J3DWT952Y1GK4GWYBQK9A4E0
https://www.ebay.com/itm/3715948221...lp:2332490&itmmeta=01J3DWT952Y1GK4GWYBQK9A4E0
OK, you've all convinced me - new pistons ordered from my EU supplier: https://www.xs650shop.de/
While waiting I decided to put the brakes back together for practice. I think someone above said it's about an hour's work... haha.
My main issue was getting the pistons out again after trial insert - what's the technique when you have two, if one pops out before the other? (I don't have access to a grease gun with suitable nipple, or a compressor.)
But 4 hours later I got it right and now my brakes retract fine and don't lock onto the disk as previously. When I get the new pistons I'll set the timer and see how much better I am.
Thanks
While waiting I decided to put the brakes back together for practice. I think someone above said it's about an hour's work... haha.
My main issue was getting the pistons out again after trial insert - what's the technique when you have two, if one pops out before the other? (I don't have access to a grease gun with suitable nipple, or a compressor.)
But 4 hours later I got it right and now my brakes retract fine and don't lock onto the disk as previously. When I get the new pistons I'll set the timer and see how much better I am.
Thanks
For cheap, I got an extra Brake Master cylinder from ebay. Spare hose and brake fluid, I just hook up to the individual caliper. Use vacuum bleader that attaches to air compressor, then pump away and force the piston out. If you have dual calipers and not my setup, you want to block the one that is moving so once it starts moving some, it won't pop out. then the other will start to move. It really helps to do this before you pull from the bike if the MC is ok. If not, then use the method I describe, grease gun or air. I like what I do with the spare MC cause It always works. (so far). I do waste brake fluid but not so much time.
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