ok so today we tore down the upper half of the engine and slid the jughead off of the piston and it was definitealy the piston rings bad, it had about a half inch of oil on top of the piston lol, but what the prob is... is that i was TOLD it was bored 40 over but im not sure if it was or not so we measured it with calipers and it measured 2.910, i dont know what the stock size would be but i was wondering if this size i measured would truly be 40 over stock size if thats how it works or not. and by the way i just bought a 1985 kawasaki klf 185A for 25$ and all it needs is coil pack and hoses for the carb lol it has BRAND new nobby tires on the front so that was worth my 25$ b ut i would appreciate any help on the piston situation

 

well stock is 74mm..so convert that to inches and theres your answer.

 

The piston/cylinder & valves/guides will have to be measured ..

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