WTB - XJ1100 Rear Master Cylinder

Everything on the bike seems to be in excellent shape with the exception of the rear master cylinder. I got it off and discovered the piston corroded solid in the cylinder, even if I get it out it's probably toast. Any help would be GREATLY appreciated!!

 

I had the lucky experience, if you can call it that, to have my rear master cylinder give up the ghost on me just as I was making my way up and out of the underground car park at work. Pressed the pedal and...NOTHING! I just kept sailing forward, fortunately at only 20km/hr and heading for the automatic boom gate.

Leaving nothing to chance I decided a genuine Yamaha part was a better idea for the fix than an aftermarket part on this occasion. Cost around AUD$80 (around US$90) for my XJ900. It came with the piston and seals - all you need for a refurbishment of the part.

If the piston is stuck in the cylinder try soaking it in something suitable to try to extract it. Someone on this site might have a few ideas on that point. If the inside of the master cylinder bore looks OK I'd clean it out and make sure the passages are clean and open and then go for the Yamaha rebuild kit like I got. Takes not a lot of time to put it together (follow the Haynes manaual instructions to the letter because seals etc have to be set up as described).

Once in place and re-connected, bleed the brakes and away you go.

 

I'll second the suggestions of redcentre003......soak with a penetrating oil, and them maybe even heating up (gently!) the ouside of the master cylinder (like in an oven for 20-30 minutes---yes, it will stink!), then hit it with more penatrating oil, and put some cold waster (gently!) or some ice chips on the piston (only on the piston). You can sometimes get the piston to shrink just enough, and the sleeve to expand just a hair, and that's enough to get that feller moving. If you have an air pressure fitting that will screw into the m/c outlet port, or a rubber-tipped air "gun", that helps, too. Frozen calipers usually respond well to the above desribed process and require about 120 lbs. of air pressure to get un-stuck.

 

Excellent suggestions gentlemen! Thank you! I've had it soaking in Liquid Wrench for a couple of days with no luck, think I'll try heating next. I also found someone who may have one over on XS11.com. One way or another, she will ride, and stop, again!

 

Well, finally got it out. I drilled down the center of the piston and used and easy out. Came out slicker than snot. The cylinder is in great shape so I wont need a different one after all. Thanks to those who responeded.