Spacer Set SIP clutch cover, drum, clutch plate, drum, fixing plate for Vespa 50-125/PV/ET3/PK50-125/S/SS/XL/XL2 aluminium, thickness 1.0mm, 4-parts, for tuned engines As soon as larger clutch conversions are necessary to allow for thicker clutch plates you will soon reach the limits of the space under the standard clutch cover. The gasket surface spacer provides the extra room needed. NOTE: In the event that the tire then rubs against the clutch cover, wheel spacers can resolve this problem.