Hi all - long time lurker first time poster - be gentle!
I'm trying to bleed my front brake after a dip in performance. I've managed to do this in the past without problems, but this time I can't pass any fluid from the caliper to the master cylinder, or vice versa, unless I really force the syringe.
I've disconnecting the master cylinder from the brake hose, and can freely pass fluid via the the caliper and out of the hose, so the problem looks to be at the master cylinder - any ideas what to try next?
James - is this you?
Not James, no.
Sounds like somebody else with a similar problem?
TBH it sounds like the seals have gone.
Old piston
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which had issues
and the new version that is OK
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check yours out.
TBH it sounds like the seals have gone.
I had a similar problem a few years ago. Replaced the pistons, and they're good to go again. Apparently the old plastic bits weren't the best - the new ones are aluminium (or some form of metal).
Bear in mind that if you do replace the piston the replacement ones sold for K18's are slightly different (apart from being metal) in that they are the same as in the K24, therefore with the addition of a FCS adjustment kit, as well as the piston, you can add bite point adjustment and turn your K18's into K24's.
ie;
Piston;
http://www.ukbikestore.co.uk/product/143/fd40065_20/formula-oro-lever-piston-kit.html
FCS lever;
http://www.ukbikestore.co.uk/product/143/fd40066_20/formula-oro-fcs-adjustment-kit.html