I have mechanical disc brakes (TRP Spyre-C), second year. Last year I removed and mounted wheels without problems. This year I am all surprised because I cannot adjust the rear brake.
Front -- no problem, plenty of space between brake pads. I can insert 2.5 hex key between pads and even tilt the key a little. Next I can screw in pads-screws, and then fine-tune it with the barrel.
Rear -- I cannot even insert 2.5 hex key between pads (in their neutral position). So basically I can barely put the wheel on, but I cannot adjust brakes at all.
Did I damaged something? Is there is some element extra to adjust?
I already checked and rechecked:
cable tension -- cable is completely loose
barrel adjuster -- all way in (meaning it cannot be shorter)
pads-screws on both sides -- (un)screwed outwards
pads wear -- I just put an identical pair on front and rear
I also removed pads, cleaned the interior (I was thinking about some sand grain), no change.
Granted, last year rotors where 1.9mm thick, current ones 2.0mm, so maybe this explains why I was able to put the rear wheel (but I am sceptical), but the problem remains -- why such a difference between gaps? Could it be my rear brake is faulty (by manufacturer) and I simply didn't notice? Or there is some magical screw (to fix it, or disassemble it)? Is there a way to remove the brake lever (the one at the brake, not at handlebar)?
Any help in solving this mystery is welcome!
I upgraded in the rotor diameter as well, front from 160 to 203, and rear from 160 to 180 with appropriate adapters, just as sanity check I unscrewed brakes from adapters and it didn't change a thing.
Last year -- Sudden gap between disc brake and pads? -- I got mud (?) in front brake which had curious effect -- it didn't damage anything, at least I didn't notice, it didn't peel off the pads, yet it widened the gap of the front brake. So from current perspective it looks like it was a fix-therapy and I wonder how I can perform such fix-therapy for rear brake on demand.