Working on a bike for a buddy of mine. His rear brake lever suddenly became extremely squishy after getting a tune up from a LBS. I started a brake bleed and could not get fluid to flow from the lever bleed port to the caliper. I could make the lever move by pushing fluid from the caliper. Thinking it was a clog I worked it for a while and had no luck. I then took apart the lever reservoir to see if I could find the clog. When i opened it up the diaphragm was out of place and seemed too big. I could not get it back together correctly.
I ordered a new diaphragm to see if that will fix the issue, but I have never seen this before.
Is this the correct source of the issue or could a clog possibly cause this? Did something the local bike shop do cause this? Are there preventative measures to prevent this in the future?
Or am I an idiot and the diaphragm is fine I just doesn’t know how to put this lever back together?
by PeteYeesh