rear spocket

[j400ex18]

thinking of running a 36th tooth sprocket in the rear will i be able to tell the difference

[cals400ex]

i actually lost power in 4th and 5th gear when i had either 15/36 or 16/38 gearing after i put my sparks pipe on. i am not exactly sure why but i guess it was from the sparks wants the highest possible rpm possible. with my stock pipe, i had good luck with that gearing though. so, i would look at your set up and go from there.