On to motorcycles.
The speed ratings of the tires are as noted above. Motorcycle tires use either the speed rating in the body of the designation or in the load index and speed symbol.
Speed ratings are European Commission for Europe Regulation 30 (ECE 30) European Indoor Wheel Test Standards.
Tire speed ratings are not required by U.S. law.
Tire speed ratings M,N,O,P,Q,R,S,T and U - SCTA - Any tire designated for motorcycle use is permitted 0-70 mph
H 130 mph SCTA 71-130 mph
V 149 mph SCTA 131-150 mph - If shaved, up to 200 mph. Generally, shaving removes the bulk of the rubber and only leaves a thin layer with no cords showing. This reduces the centrifugal forces on the tire.
Z (Listed as ZR in the rule book) SCTA - Up to 200 mph - This would include Y and W rating as they are above Z.
Over 200 mph - speed ratings no longer apply.