Generally
This is the perfect tool for trouble-free piston assembly. A turned cone made of plastic to mount the pistons in the cylinder bore with. It is exactly the same diameter as the cylinder on one side, it tapers and becomes larger on the other side. Holding the taper against the cylinder bore push the piston straight down, the piston rings are pressed together and the piston slides into place without a problem. Do not forget to lubricate properly with engine oil when assembling the piston. This piston ring taper fits Standard cylinder diameter, i.e. 3.8125″ = 96.84mm
