I've noticed some vibration from the front brakes when braking from higher speeds. I suspect one the front discs has warped slightly. The bike is just over 2 years old, low mileage circa 6000, never thrashed or abused. Head bearings properly adjusted, no wheel balance issues, never used in the winter sludge. Has anyone out there had any joy with a warranty claim for this problem? I've never encountered it on any my previous bikes.