Has anyone else noticed that if you lay a bike down or roll it along on the back wheel with Avid brakes, they sometimes then let the lever come back to the bar? It's not the end of the world, you just pump the lever a few times and everything is back to normal. I've noticed this on a few bike now but it only seems to be Juicys. I did wonder if it was a sign of air in the system (even though the brake doesn't feel spongy) but bleeding doesn't make any difference. Sometimes both levers will do it but it does seem to be the rear more often than not.
Anyone else notice this or am I just suffering some strange jinx?
its air in the system, to get it out you need to follow the bleeding instructions religously (ie: take the caliper off the bike, and tap it to get the last of the bastard air bubbles out)
Left a bike upside down for a week or two, and the brakes pulled back to the bar when i righted it. Next day they were fine again.
I've run several bleeds following the Avid two syringe suck/blow method. There's no more air coming out!
However, if you're sure it's air, I'll give it another go.
They definitely need bleeding. 110% of fact etc.
so this isn't just some quirk of the design then? There's a lot of these out there that need bleeding then. Quite a few not been touched since they left the factory!
Fitted a set last night that went to the bar the first few pumps. Now they're fine.
atlaz, isn't that one just going to be the pistons re-adjusting?
What I'm talking about it when you lay the bike on its side to open a gate/go for a pee, whatever, and then the blade comes back to the bar. After a couple of squeezes it's fine again. No sponginess, no fade at speed, just does its job.
well, after carefully bleeding one of said brakes, I can say that it has made sack all difference. Feels fine to ride. No fade, no pump, no sponge, just comes back to the bar when inverted!
Haha! Fixed it!!!!!
I think.
Before you finish bleeding the lever, try inverting it and giving it a few taps and then try sucking more air out. I'm convinced that air gets trapped under the diaphragm, inverting it then releases it and allows you to suck it out(or allows it into the system if you leave it there and pull the lever).
Cheers Coatesy.
What it seems to be is that when you suck the air out of the lever, it causes the diaphram to collapse. So, all I've done once I think all the air is out is to push back on the syringe to reinflate (?) the diaphram. Seems to have worked on two of the brakes so far. I'm just going back into the garage to try the third and final brake.
In my defence, it doesn't mention pushing in the bleed instructions, just pulling.