Help on rear master clyinder

[Dan Thompson]

ok so i bought a rear master cylinder (2nd hand) the rubbers were shot (was never told!!! ) so bought a rebuild kit and rebuilt it today, just put it on the bench and connected it all up and bleed it all correctly and its still not working!! we think its sucking air in somewere but we dont know were all the fitting are new and i know its not them. any advice guys? cheers

 

[Awk08]

so, you have the complete system built, and are trying to bench bleed it ???? or is it on the bike ????
what make system you foolin with ???? blaster, banshee, streetbike ?????
i know when i do my gsxr systems they are sometimes a real biotch to bleed, even needing to bleed each section seperately sometimes, start by cracking the line coming out of the master, once you get fluid there, do the same where the line connects at the caliper, and i always pre-fill the caliper as much as possible before hooking it up, then, with the caliper off the bike, hold it up higher than the master, with the bleeder facing upwards, and try re-bleeding, making sure to pump the pedal a few times, then hold it down while cracking the bleeder, tighten the bleeder,
then and only then will you release the pedal
NEVER, EVER, EVER... pump or release the pedal while the bleeder, or any line is cracked open, or you'll be chasing your tail all day !!!!! each fitting, line, banjo bolt or bleeder must be tightened before releasing the pedal !!!!!!!!!!!!!!! < yeah i said that part twice, it's the most common mistake
also are all the copper crush washers in the system ????
one on each side of every banjo bolt

 

[Dan Thompson]

yeah ive done all of that we think its not powerful enough for my caliper i have a caliper off my go kart but it was oridionallt for like a buggy or something as it is huge!! haha

 

[Awk08]

i have no troubles with any atv/bike master running the dual piston gsxr calipers i run

 

[lasxgames]

http://www.blasterforum.com/do-yourself-20/bleeding-your-brakes-34859/

http://www.blasterforum.com/off-topic-7/blaster-websites-13531/index6.html

 

[lowkhalbalr]

ok so i bought a rear master cylinder (2nd hand) the rubbers were shot (was never told!!! ) so bought a rebuild kit and rebuilt it today, just put it on the bench and connected it all up and bleed it all correctly and its still not working!! we think its sucking air in somewere but we dont know were all the fitting are new and i know its not them. any advice guys? cheers

everything has to be spotless clean. clean hands, clean tools, clean work space. also buy new copper washers and be sure not to scratch them. scratches cause leaks.

also, i used an anaerobic gasket sealer which proved very useful. pm me if you need help.