ok here it is. i just bought a 1998 kx125. at first it was running premium in it but now since the mods were done to it by the previous owner he started running 110 octane. the engine mods include head milled one thousandth of an inch for high compression,the cylinder is steel sleeved still stock bore but set up for an over bore, wiseco piston, v-force 2 reeds and cage, and fmf exhaust. i would like to go back to running premium gas since 110 octane is costing me 9.50 a gallon. will the engine be ok if i go back to using premium gas in it.

 

you want to put the compression back to the facotry settings if you are switvching because the 110 burns cooler so you will burn your engine.