consider myself ok at bleeding them, but cant seem to get this one right. lever seems to have too much play before biting, and as im pootling along on the flat, the pads are 'singing'. i put a bit of pressure on lever and it stops, let go the lever and it soon starts again. i could keep riding forever with just a slight bit of pressure on the lever and itd be fine. let go and it sings.

id say i can get the lever to halfway before it feels like its biting the brake.

so…….not really sure why, but thought a bleed might cure it. did it as per usual. pushed pistons back, 'push me pull you' for a few times, then cable tied the lever to close reservoir, and pulled from both ends to get rid of any individual air bubbles. then released lever, 'push me pull you' a few more times, no bubbles apparant, jobs a good un.

but……..lever still seemed to be halfway or so before biting, and yes, pads started singing again. so i havent really made it any better, just bled it for nowt really.

anyone got a reason why this should happen? im thinking air would make it spongy, so its not that. its as though theres not enough fluid in maybe, and the lever is taking up dead space when i start to close it? so theres no pressure on pads and theyre vibrating? just a wild guess tho.

thanks for any suggestions.

I had this problem with my oros. My problem was that during a pad change I'd pushed the pistons too far in. This left the pads to float about and vibrate against the rotor leading to a singing noise and massive lever throw. I dropped the wheel out, gave a few gentle squeezes on the lever to push the pistons out a bit, problem solved. Oros seem to be crap at adjusting for pad wear so I now do this on a regular basis to keep the bite point where I like it.

Hope this helps.

I have just sent my oros off to propel with this symptom,I suspect it is a problem with the small seal that is fitted on the lever/piston rod thingy,Until this bit is replaced you cant get a proper hydraulic lock from lever to pads,hence half travel from the lever.

Its worth noting any brake system should be thoroughly cleaned, and blead up, using new pads to avoid an inacurate base setting for fluid amount,pad clearance, and braking performance. hth

you cant get parts from crc either. 😥

GaVgAs – UK bike store have all the formula parts you could wish for as far as I am aware.

doh, i dont like it when its a problem i cant sort myself :-/

can you pinpoint the offending chappy on a diagram so i can try and suss what it is i need exactly? and do propel need to do it or can i do it myself?

shackleton, i wasnt aware you could push them too far in. id have thought theyd just compensate as soon as you squeezed the lever.

ta

on this diagram

thinking about it tho, ive not long had em back from propel cos they changed the pistons over from plasic to metal. so id have thought the insides were in good order :-/

just a quick question. i can remember when i cable tied lever to bar, that the syringe fluid expanded, as it should. but cant remember if it contracted again when i released it. could that be a problem? cant see how but just wondering.

ta

I'm not sure they can be pushed too far back, but they are certainly poor at self adjusting.

That and a bit of a prissy bleed are about my only criticisms of an otherwise excellent brake.

Its the "piston kit" you need Code(FD4006520) 😉

hmmm thanks for that gav. but thats the bit that propel changed for me not so long back, so that p*sses me off somewhat >-(

altho they did do it for nowt i spose 🙂

We get similar long lever travel problems on avids, seems to be a lack of lube on the caliper pistons/seals not allowing the pistons to slide out as they should, rather pulling them back into the caliper when you release the lever.Try cleaning up the caliper and working a bit of silicone lube into the piston and seal area.

Still think you should try what I said as it worked for me! You can't push the pistons in too far but yu can push them far enough back that you get long lever throw.

I seem to have the opposite problem. My oro 24s needed new pads and when fitted provide excellent resistance training. I have done all the usual things, cleaned everything, pushed the pistons back as far as possible, centred the calipers, it seems the same for both front and rear brakes. I have only just bought these so have not had any use yet…

Any advice welcome, please?

Have you pushed back both pistons at the same time? You may have to keep the pressure on for a good few seconds.

If that fails then the brakes may have been over filled and you may need to let some fluid out of the system (last resort). Turn the bike upside down, undo the caliper torx bleed screw, gently squeeze the lever until fluid emerges, once you feel enough has dribbled onto the carpet do up the torx screw and release lever. Now try pushing the pistons back in as before.

Thanks for that Shackleton, although having just cleaned the carpets I think it might be an outdoor job!