Originally Posted by
rsacilotto
+1 I have 6510 levers, calipers, black KoolStop, all work fine, great stopping power. Have you tried cleaning the pads with alcohol to remove any dirt?
Yes, I also had a set with the OEM pads and had no complaint. I wondering if maybe it's just the front caliper, as the rear working by itself would have the effect the OP is describing.