KXT VS KX pistons in a tecate motor

[TecateDan]

I've run both the KX jug and the KXT on my tecate now and for me I prefer the KXT for the type of technical riding I do. My question is related ot the window port size on the pistons that come with each motor. The KX piston has larger windows while the kxt has smaller windows. I know theoretically the larger windows should make more top end power, less rotating mass etc and that what it did in the KX jug but the KX also has the extra eyebrow ports so not sure how much comes from the ports in the cylinder and how much comes from the difference in window size. Has anyone tried the two different pistions in stock kxt Jug? Would love a little more top end but don't want to give up my low end and was wondering if this would be worth me tearing down my motor to swap.

[just ben]

I'm not sure what pistons you are comparing (stock vs aftermarket ect...)the kx from 78-86 uses the same piston as all year kxt's. the only difference is the the piston should be drilled to lube the exhaust bridge.

[TecateDan]

ill get some pics up tonight but the piston that came with the cylinder from swienheart def has larger windows than the NOS pistion i have. Any thoughts on the effect overall ben ?

[TecateDan]

Stock on the right

[christph]

Like you said, the theoretical advantage of larger windows would be less restrictive flow which may be noticeable at higher rpm. I'm thinking about getting Wossner's KX piston for mine. They don't specifically list it as working with the Tecate but they should work. Nothing against Wiseco, I'm just ready to try something different. Plus Wossner puts a coating on the skirt. I'm interested in seeing how that holds up.

[just ben]

what do you mean by stock? what it was in it or an oem piston? a stock piston is cast and has a slightly raised circle in the center and will say arf on the bottom. I have wiseco pistons with the same part# that have small differences.maybe  the oem was revised,maybe the piston with bigger holes was worked on? maybe they are not the same brand? but I know they all used the same piston, as well as the kdx 250