The funniest part is that it was run this way!
I would have replated them too. I picked this 4/6 up as a basket case. It was already sleeved and ported. It came with one cylinder off, freshly honed and a NIB Wiseco piston. I tore the motor down to replace the crank seals (found bad crank/rod bearings), this is when I noticed the ports, the cylinder with the missing ports was still installed on the motor.
I'm going to drop the cylinder to my local sled shop tomorrow, they're going to cut the ports for me.
Ported, Aaen pipes, studded track... I bet this 4/6 is really going to fly!