I did my first bleeding and had some issues, ended up changing the caliper. After a thorough bleed (what I think) it felt good when the bike was horizontal. Now it was hanging for a few weeks and the brake feel/brake point is very soft. As in the picture I can basically pull it all the way to the bar.
When I put it back horizontal after 20x pull it feels good again. What is the problem? It seems thight/no leaking. Bad bleeding?
by bikesailfreak
2 Comments
Rather a physics than a bike mechanical guess, but it sounds like you don’t have just the breaking fluid in your system but also a bit of air.
If the brake line is 100% filled with hydraulic fluid, you can orient the bike in any way and it won’t affect performance. The fact that the performance suffered after hanging the bike, and that pumping the brakes improved it, indicate that there was an air bubble in there that migrated up when the bike was hung up. So, the orientation of the bike wasn’t the root cause of the softness, but it exposed a latent problem.
You might be able to take advantage of that phenomenon to salvage your bleed job. Hang the bike up again, keeping the lever squeezed using a rubber band or scrunchie. Now, the air will likely have been forced to the top, by the lever. So, install the fluid cup at the lever, fill it, and see if that helps.