 You don't need to be an 'investor' to invest in Singletrack: 6 days left: 95% of target - Find out more
Recently changed frames and moved components over for the build. The only change in the brake set up was that the rear brake hose now runs along the chanstay below the caliper then rises up to the caliper mount(its a Lappierre zesty frame). On the old frame ithe hose all pointed down from the lever to the caliper. I am now experiencing intermittent loss of pressure in the system when the bike is left for a while after / between rides. It takes a good 5-10 minutes of riding , with the lever hanging completely slack , to get the pressure back up and the brake functioning again, with the lever springing back as normal. Then it is working fine. I obviously thought it was an air lock somewhere, so I bled them , replaced the hose (as thought maybe a bit too short for the new frame) and carefully bled system again, but it is still happening. It's not a major problem as the brakes work eventually , but its annoying and I want to sort it. Any ideas what to check next?
Bleed them again.
It has to be air in the system, so either a leak somewhere or they just need bleeding properly.
ETA: the path of the hose is completely irrelevant if there is no air in it.
I sent my SLX brakes back under warranty. They were leaking from the resevoir. I would experience no lever feel at all after a few days of non use, and would have to pump them repeatedly to get some pressure before a ride. Eventually they stopped coming back, and after a lot of faffing, repeated bleeding etc. I sent them back.
If I looked closely at the top cap of the resevoir and pulled the lever hard, I could see fluid oozing out where it joined the res.
I googled it at the time and I wasn't the only one.
Incidentally, Tweeks sent me a new rear brake within a few days, no quibbles. I think Shimano were aware of a problem and just replaced it.
cheers for the replies guys - sbob: the brakes have been bled properly twice so im not inclined to think there is an issue with air trapped somewhere unless it is being caused by a leak. cbmotorsport - this sounds exactly like the problem I am experiencing. Will check out the lever. thanks!