Sherco 250 Piston kit

Piston Sizes

A 72.75mm
B 72.76mm
C 72.77mm
D 72.78mm

The factory recommended piston to cylinder tolerance for the 250 is 0.024 to 0.035mm in the 09 manual (0.035 to 0.040mm in the 03 manual?), if you are considering putting the next size up piston in please be aware that your original piston will have worn down and any wear in the cylinder is unlikely to be uniform down the bore so please check the bore size all the way down the cylinder and from left to right as well as front to back, the factory measure the piston and cylinders at 24 degrees C. The piston is measured front to back and 19mm up from the bottom of the skirt, be aware that the pistons are manufactured tapered (larger at the bottom) and oval (larger front to back) to allow for unequal expansion of the piston in use.