SLX brakes which up until recently performed flawlessly. However the front is causeing problems.
At the start of a ride, there is little power even with the lever pulled as hard as I can and the squeal is horrific. It gets gradually better into the ride as I am using them, however, once the ride is finished and bike packed away, its back to the same problem on the next ride. I've changed the pads which initially helped, before it starting again. They are generally ok after a lot of use.
Could it be the rotor ? If so can you recommend a good way of cleaning them ?