ORIGINAL: selena1718
hi,just put a new big bore kit in my baja,i have spark,i have a new plug,ciol gap is good,ive tried numurous things,the only way it starts is if i put a littlle 2 cycle oil in piston,and it only runs for a few seconds,does this mean i have low compression,and how do i fix it,thanks,oh buy the way ,i do have the piston arrow facing the exhaust port,.
When you installed the new head and gasket, did you check you squish height? It sounds like you have way too much squist height, and thus a very very low compression ratio, and putting in 2-stroke oil to reduce that compression ratio by temporailiy causing a hydro-lock situation that actually temporarily establishes the correct compression ratio, at least until it all burns away.
If your squish height is too much, you must get a thinner gasket. I would get gaskets of different thicknesses so that you can play with them to get the correct squish height.