2009 C-14 Front Breaks

[UP]

OK. I think I read a post on this already but Here is another. The front breaks on my 2009 pulse when slowing. It is most noticeable when roll slow and applying the breaks lightly. Not so noticeable at speed or when breaking hard. I sand papered the rotors with some result but no complete resolution. Pads look good and generally I am very easy on the breaks. I have the 7,500 service coming up and will complain about it. $500 + for new rotors ain't in my future. Thoughts? UP

 

[mass]

My 2009 only has 5600 miles on it but no pulsating brakes. Your bike is under warranty so at least let your Dealer know you have a problem. Pulsating brakes don't guarantee warped rotors. You could have low or contaminated brake fluid or air in the brake lines. You could also have a sticky piston or glazed pads. The warranty should cover it. Kevin

 

[Fred H.]

There have been quite a few folks who have had rotors replaced under warranty. Some folks say you can scrub the rotors with a ScotchBrite pad and knock any brake pad residue off them and that will sometimes cure it. I would probably suggest following up with denatured alcohol or brake cleaner and a clean cloth to get them totally clean. If that doesn't help, then you may need to press the dealer for new rotors. Be gentle on the rotors when cleaning them. It doesn't take much pressure to distort the soft aluminum carrier that they are mounted to. Even a .004 inch vertical variation in trueness of them is enough to cause a mild pulsation. I was able to "tweak" the rotors on my 2008 back into alignment using a dial caliper mounted to the fork leg and carefully putting very mild pressure with just three fingers on the rotor carrier (not the rotor) and pushing. It was pretty amazing how little force it took to make a change of .002 inches. I got both front rotors to within .002 inches all the way around, and all my pulsations went away afterwards. Torque of the rotor mounting bolts can also throw them out of alignment. They all need to be torqued evenly all the way around. One bolt too tight can throw off the alignment. Here is a photo showing how I did this on my old C10 about 10 years ago. I had to fabricate a bracket to hold the dial caliper to the fork leg, and I then used a crescent wrench and just a little pressure on it to tweak the rotor carrier so that the disc was true. On the C14, I didn't even need the crescent wrench, just pushing with my fingers on it was enough. It takes VERY LITTLE FORCE to bring it into alignment, so go very easy on the carrier when you do this. Two or three fingers is all you need. You're only trying to adjust it by thousandths of an inch. Also, notice the force is not being put on the disc, but rather the carrier it is mounted to. You also should probably only employ this method as a LAST RESORT after you have exhausted all other options and if the dealer has refused to warranty them. Obviously the best solution would be to get the dealer to give you new rotors, and they might be less willing to do that if they knew you had already tried an unorthodox fix on them already.