This 57 mm piston gives 128 cc.
The piston has two 1 mm chromed steel rings that are much stronger than the original 3 mm cast iron rings.
The piston pin is moved up 1 mm to give the same scavenge ports duration as the Sport cylinder and the scavengeports in the piston is 2 mm higher.
The pistonskirt is 4 mm shorter for increased inletport duration.
The piston dome is 3 mm lower to lower the weight and compensates for the increased compression with 2 mm overbore. We need 15 pre-orders to start production.
That is why the price is set at 500 Sek.
After the quota of 35 pistons is filled the reminding 1350 Sek should be paid at delivery. Ordinary price witout deposition will be 1950 Sek.
Modification, Porting and Mounting instruction will be included with each piston.