I rebuilt my clutch master cylinder cause the old one was sticking. The piston won’t return once pulled in.  Put new kit in and same thing happens. Piston sticks and spring won’t push it back. Cylinder looked good thought the old seals swelled but new do the same. Using dot 4.  Any body have an idea.   Thanks 

It uses mineral oil not dot4.

Dot 4 will swell the seals in a mineral oil system.

You will need a new Clutch M/C kit (mineral oil version), two new slave cylinder seals and a flush of the lines to get all that DOT4 out.

If it has the original AJP M/C cap, it will be green, not black, and say "WARNING Use Mineral oil" on the top.

My caps say dot 4 and the rubber is black

i thought I swelled the last seal cause I used mineral oil instead of dot4. What causes the rubbers to swell Mineral oil or dot4? Where can I get slave seals without spending $40 for a complete kit. Thanks

A standard 2011 TXT Pro, Racing or RAGA it is a mineral oil system. (and has been that way since 2004) It has had the incorrect Cap and/or Master cylinder put on it at some stage.

Even though the master cylinder pistons look identical, the seal material is different.

For the mineral oil kit the Gas Gas Part number is BT460102811

And the manufacturers (Braktec) Part number is 150.00.602C

 

My caps say dot 4 and the rubber is black

i thought I swelled the last seal cause I used mineral oil instead of dot4. What causes the rubbers to swell Mineral oil or dot4?

Thanks  the guy I bought it from must of changed stuff.  Sure glad some of you guys know your bikes!?