yz 125 problems

ok so i have an 01 yz 125 that i already knew had somewhat low compression. but it still ran beautifully barley any bogging. now it is fouling out plugs left and right. like if i go for a lap around a track or for a hill climb it bogs out and fouls the plug. i tested the compression and im at about 85-90 so i know i need a top end. but i just want to get a more experienced opinion. the bike runs after i put a new plug in or i clean the old plug. but then shortly ater it bogs out and dies once more. so i guess its a new top end? or could it just be bad plugs aswell?

replace the top end

Kan gave you your answer, fix your top end your bike will stop fouling plugs.

alright thanks guys will do, just wanted to make sure i didnt need anything elese to fix the problem

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