I have an '09 FXDB with a rear break loud humming issue. After highway riding, breaking around town causing a loud humming at the end of each stop. I was wondering if this grooving on my rear disc could be an indication of what might be causing the issue. The grooves are deeper than the pics look (deep enough to catch a fingernail). Bike only has 5400 miles BTW..

 

Any thoughts? Suggestions? Ideas?

 

Mine is the exact same way. It only happens sometimes, bu when it does, its embarrassing. I was at the dealer once and I asked one of the service guys about it, and he knew exactly what I was talking about. He said he'd scuff up my brake pads for me and clean the rotor....for free. He also said that its not a big deal, some of them do that, to include his.

I believe him because he was willing to fix it for free (on dealership time) and he said his does it too. I may be mistaken but he said something about glazing of the pads i think.

 

The reason why that is happening is because the choice of Sintered brake material. Look it up on the web and find out about the material along with the advantaged and disadvantages of using that type of brake pad. If you continue to use the same compound, please remove your calipers every 2,500 miles and scrub the pistons to remove all of the brake dust. This brake dust is very corrosive which means it will corrode your nice shinny wheels if not removed. Go to my site pages found CLICKITY here. You may service your brake pads by choosing any of the DIY pages that is your calipers. Brakes
Brembo Brake Maintenance Guide PDF Download
Twin Cam Brake Maintenance Guide PDF Download
Twin Cam Brake & Control Illustration PDF Download

If you choose to change your brake pad material to an Organic, there are many good pads out there. Use actual research and do not ask someone who has as much experience as you do except they talk with authority and BS you.

In 8K miles with a HH pad (Sintered), this is what your caliper pistons look like!


The Sintered brake dust builds up around ther piston and does not allow the piston to retract fully a little each time. Eventually the pads start rubbing all of the time, producing heat than warping your rotor and/or wearing down your pads. The seals are the only mechanism the pistons use to retract, no springs to pull them back.

If you feel as though you do not need brakes or you wish to argue that you never clean your calipers and ....(all of the BS I do not wish to here) I do not care if you clean your brakes or not. It is your bike, life, life of your passenger and those around you. The only impact I would experience is that I may-be one more parking space closer to the front door to "Catch the Blue Light Spacial".

I make the effort to invest my time to make these posts, host these photos, and provide money to support this great site and to inform our members with truthful information. Do it or not is OK by me, The End.

 

I do appreciate all the time taken on the responses (I will take #2 under advisement), only thing is to response #1, my dealer thought the same... Cleaned the and treated the surfaces, even said the same, that they are taking the hit on the cost to do it, but the same issue reoccurred 1 hour after I left the dealership. the main thing I did however notice was that the break disc became too hot to touch even when not being used. I went for a 30 minute ride, not using the rear break at all, and while the front disc was simply warm to the touch, the rear disc would sizzle when I touched it with a wet finger. I did get it back to the dealer and turns out that it is (what they called) a lazy break caliper, which basically means from what I can gather, that it is making light contact even when not engaged. I didn't have time to have any work done, but in 2 weeks I am bringing the bike back to have the repair done, will post exactly what they do once done...

 

Cool. I'll remember to check my rear disc next time I ride to see if mines rubbing too.