My rear Shimano disk brake is not working very efficiently, despite several bleed attempts. The front is absolutely fine, so I'm fairly confident that I am bleeding them properly. When I opened the reservoir on the back brake, I saw that the little bit of metal highlighted by the arrow in the picture below was not seated securely in the reservoir. I'm guessing this is the problem. I've tried re-seating it, but it always seems to come loose again.
Has anyone fixed a similar problem or is it new brakes time?
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If you can confirm the bit is the problem, why not try getting a new lever.
Unless you're looking for excuses to a buy some new kit 😉
That's just a baffle-plate, it stops fluid being squirted into the air when you pull the lever without the cap fitted, shouldn't really make any difference to the performance.What problems are you experiencing, long lever travel, spongeyness, lack of bite?
The brake is spongy with no bite. I'll try bleeding it again and see if it makes a difference. I wondered if the plate might be letting in air somehow, but it's probably just poor bleeding. Thanks.
Try to make sure there's an upward slope all the way from the caliper to the lever, if you have any humps in the hose, they're a likely spot for an air pocket to get trapped in.