In this article, we use so-called affiliate links. With every purchase through these links, we receive a commission from the merchant. All relevant referral links are marked with . Learn more.
The power lost through a grinding disc brake is negligible. But the squeaking and grinding are annoying in the long run. Fortunately, every MTB disc brake can be realigned with just two screws. However, the tricky thing is that the design of the brake callipers leaves only a few tenths of a millimetre of space between the brake disc and the brake pads on the left and right. In our video guide, we reveal a tip on how to adjust a disc brake on a bike quickly and precisely.
But not all brake grinding is caused by an incorrectly adjusted brake calliper. The causes of annoying noises on MTB disc brakes can be manifold.
That's why a disc brake grinds:
- If the Brake calliper not centred to the brake discthe disc brake grinds constantly, regardless of whether you are pedalling slowly uphill, just rolling along or descending into the valley. The solution to the problem is to adjust the disc brake correctly. We show you how to do this in the video instructions below.
- With Mountain bikes with conventional quick-releases (QR, quick release), often only the wheel is installed at an angle. This can no longer happen with thru axles. In some cases, however, the thru-axle thread in the dropout at the rear must be aligned for the correct fit. Otherwise, the following applies to QR bikes: Simply loosen the quick release, stand the bike up straight on level ground and close the quick release again.
- Hydraulic disc brakes can sometimes be supplied with Too much brake fluid be filled. This means that the pistons cannot retract far enough from the brake disc. In this case, the fill level of the brake fluid must be corrected and the brake must be bled.
- In many cases, only the Bent brake disc and therefore rubs against the pad in some places. You can try to bend the brake disc back carefully. Caution: Do not apply grease or oil to the brake disc. The problem usually resolves itself once the disc brake has been braked really hot on a long descent.
- Older brakes in particular can Piston sticking suffer. Sometimes cleaning and simply pushing the pads back in helps. In most cases, however, the brake is ready for a major service - or scrap.
Adjusting disc brakes without grinding - the video guide
In the video, we use a Sram Code RSC disc brake to show you how to adjust it without grinding. We show you how to bleed a Sram disc brake in the article "Bleeding & maintaining Sram/Avid disc brakes". We advise inexperienced hobby mechanics to visit a dealer for this repair.
With such a straightening tool (e.g. by Birzman - 11,95 Euro at Rosebikes ), bent or warped brake discs can be bent back into shape with feeling.
More on the topic of "DIY wrenching": 8 bike toolboxes from €85 in the test, and which standard tools bikers need at home
