Rockyoaks

New to this arena, I acquired a 89-90 SX550 with a complete PJS motor, with dual 38mm carbs, PJS intake, PJS exhaust, with supertrap WB. Motor had an issue where part of the skirts of the number one piston cracked off and went through the upper crank case, no damage to cylinder walls. The pistons that were in it are piston port pistons (single rings) with (2) boost ports drilled in them on intake side, about a 0.625" holes, it appears also that pin that keeps the ring from turning on the piston was ommited and moved over to try and miss the ports in the block. It is my understanding that the ring gap should miss the ports and always be facing block and no exposure to ports, is this a must ?

Do std SX550 reed piston work on this motor ?

Hope someone can help with some guidance here, or may have some pistons for this motor.

Thanks
John
913-294-4599, Paola, KS