Traditionally the arrow etched into the top of a piston is meant to point toward the front of the motor. Not so with these! These have an arrow with the initials FWD etched into it. One would think meaning forward. But no. It means exhaust in their online instruction manual. These are going in an 80” evo motor. Nothing got hurt or broken. I had the head on and tried to rotate the engine and the piston contacted the head. Couldn’t figure it out. Till I pulled the head back off and saw the line left by the half of the combustion chamber that is filled in on these big twins. See picture. I’m only out a couple head gaskets and a couple base gaskets. Just to let you guys know. They’re great looking pistons at a great price. Can’t wait to get it on the road. And would recommend them to anybody.
Quality, perfect size/fit, higher compression, better gas mileage, more power. Used with Cometic .030 steel head gaskets and Kibblewhite cylinder studs.