90 3pg piston question

[Used Parts]

got an upper rebuild kit for a 90 marathon ,the replacement piston had one horizontal port all other kits i have installed in this have 2 vertical ports, the dealer said it would work, against better judgement i went ahead and installed it, wouldn't pull itself with no passengers, put old worn jug and piston in and she ran, not good but better,is it the single small port piston causing this.not much experience in 2 strokes any help would be greatly appreciated

[tonyton]

Port location and size iis a tuning option. On a 2 cycle small port= small gas. If your old one used 2 vertical ports this will probably run best wirh those two vertical ports also. If they were in the same direction I tell you to make em match the old piston.Those ports need to align with the ports in the cylinder at a certain time to get maximum fuel flow.
If they are cut too high or too low you won't get the fuel flow need to run.
You need something with similar ports to work efficiantly.

[Used Parts]

thanks for info, i knew better than to waste my time installing it. but had to try it.this thing wouldnt pull itself empty,when i have rejugged with 2 port in the past it was like instant power