Very basic brake question
I have a 2009 GF Cobia with Avid BB5 mechanical disc brakes. They seem to be working well with the exception of one thing- the rear brake lever is easier to pull (engage) than the front brake. It's not like it's hitting the bar or anything, but it just isn't as 'tight' so to speak.
The brakes are working fine otherwise- does this just have something to do with the cable tension? Would the barrel adjuster things help fix this? If so, turn them in or out? I know I can fool with them, but just want to understand how things work.
I'm still trying to figure out how all of these things work on my bike. I've found various maintenance guides helpful with plenty of things, but want a more direct answer here.
You have two things going on here:
1) You have a much greater distance from your brake lever to your rear brake. Its also likely that you are not using housing the entire length so there is plenty of opportunity to have extra slack in the cable. On the Avid brakes, it is better take up the slack at the pinch bolt on the caliper and you might have to adjust the outboard pad closer to the rotor (since the bb5's do not allow the inboard pad to be adjusted, you may need to re-center the caliper), than to use the barrel adjuster.
2) The extra cable and housing may have some stretch (cable) and compression (housing) going on. This is especially true of cheap cables and housing which are common on OEM setups. Replacing it with higher quality cables and housing such as SRAM Pit-Stop Flak Jacket is recommended for better brake feel and performance.
look at the way the rotor is centered between the brake pads. If you can dial in the red adjuster knob (on the rear brake caliper) to move the pad closer to the rotor. This will in turn make contact sooner and in turn you will pull the lever less. Like mtnbiker said, you may need to center the rotor (by moving the caliper) if there is not enough clearance to dial the pad in closer.
FWIW I've used OEM cables, flak jackets and xt cables when I had BB5's/7's and never could I tell any difference in performance between any of them. Full housing is a plus though.
thanks a bunch, guys! i'm going to play around with them later today to see what i can do. i sometimes don't want to tinker with them when they are not broken, but i also want to learn. i guess i just have to take the dive and then learn how to adjust and fix.
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