Bicycle Mechanics - Old Brake Pads

I have promised a friend to fix up her bike. One of her complaints is that the brakes don't grab well, no matter how much she squeezes. Sure enough, I grabbed them really hard and could still spin the wheel (not fast, but it did turn).

These are Shimano Deore brakes. The cables seemed to be adjusted well enough that they should have grabbed better. The pads, however, seemed really dry and old, even though they had plenty of rubber left. The rims are aluminum--nothing special, but nothing to raise questions either.

Any thoughts? Should I start with the pads, or is there something obvious I am overlooking?

Many thanks in advance. Cheers!

Start with the pads, as you mentioned-- it's an easy and inexpensive beginning. Make sure the brakes are well lubricated, pull out the cables and look for rust or broken strands, which will rob you of braking power.

Also the cable shields could be rusted as well. And finally, check the brake levers, lube them, and adjust everything properly-- should take care of the problem.

Good Riding!

2 things to remember:
When the pad rubber hardens, it loses stopping power.
Secondly, the pad material is only a coating. If you pull the pad off and look at the braking face, I'll bet it's worn off.
Either way, replace them.

Jmlee, I realise you probably already guessed but when Tallcliff said 'lubricate the brakes', he means the arms and pivots, not the pads :). I just fitten new Deore XT V-brakes and after putting a drop of Finishline dry on each of the eight bearing points, the brakes centered much better felt much nicer to use.

If you could spin the wheel with your hand while the brake was on, you have a bigger problem than just the pads. Angel Food Cake could stop the wheel if you are spinning by hand.

Check the cables. Could the cable be frozen in the cables or elsewhere?

Disconnect the brake from the cable and check the cable movement.

Just yesterday I repaced a cable that was so frozen in the housing that I could not even remove the cable from the housing, even when using a vise, a cable-lock, and all my strength!

Replace the Shimano pads with KoolStops. Shimano pads are too hard to begin with, and only become harder with age. When I tried brand-new Shimano pads on my first-generation Campy calipers, I had alot of trouble bringing the bike to a stop.

You gatta make sure you clean your rim well also. Oil and other foreign substances get all over the rim and pads. if you get new pads make sure you clean your rim with rubbing alcohol or other degreaser.:beer:

To clean my rims, I jamb a scotch-brite pad between the brake pad and the rim, then ride around with the brake lever applied. Move pad to other side and repeat!

This gets all the grime off!

How about checking the clearance between brake pads and the rim? Ideally it should only be a couple of millimetres on either side. If it is more than this, you can pull your brakes all you want but they will not work properly.

I agree with the Koolstops as well. :)