Avid elixir 5 bleed issue
I've been putting up with some spongy rear brakes for a few weeks and decided that is finally time to bleed them today. Still having an issue though.
I bleed the brakes after carefully degassing the fluid and followed avids instructions - done this a bunch of times before too so I know it's not user error. When the bike is upright and the brakes are pumped a few times it feels ok. But, after hanging upside down for a while air has somehow worked it's way thru the system into the caliper and the lever is soft again. Flip the bike upright and pump lever, goes back to being ok. So, this tells me that there is still air in the system. Bleed them again. Everything feels ok and hung it back up to test again. 15 minutes later the lever throw goes all the way to the grip again. SOB.
So, do you guys think that there are just trapped bubbles that I have not been able to purge or is there a way for air to get past the seals in the master cylinder without showing signs of a leak via fluid seeping out? Any insight is greatly appreciated.
You have air trapped. Try taking the handle of a screw driver and tapping/knocking the caliper/hoses/lever assembly to help shake the bubles free. Also, did you de-gas the fluid before you started?
I just bled Elixer 3's for the first time (normally a Shimano guy, but my new bike came with Elixers). They should have been bled during the install, but since they weren't the shop sent me an Avid bleed kit. I figured it would be good any how since I do all my own work/building. I found bleeding the line and caliper easy, but the lever was a son of a gun. I kept at it and now have a real nice lever feel. My guess is you have air at the lever since when you hang it upside down and you get a soft spongy feel, that's where I would focus. What I did was get all the bubble out of the syringe, then pull a vacuum and pump the lever releasing it sharply. I would also push the fluid in, then repeat. I got to a point where no bubbles came out. Give it a whirl and see.
it was air caught in the lever but thought I got it all. Ended up running another 2 syringes full of fluid to get the bubbles completely out. Took a long time before the air trapped in the lever was completely purged. I used the avid method of pushing and pulling on the plunger when the lever was isolated but each time I thought I got it all the lever would get mushy again.
I know it was trapped air because every time I started a new bleed there were more bubbles in the caliper. Just wasn't sure if it was from being stuck in the lever or seeping in thru a seal somewhere. That was a giant pain in the ass. Never had this issue during any other bleeds.