u can do a leak down test but i doubt u have the neccessary tools,,,u have to air the cylinder up to 5-6 psi shouldnt leak 1 psi for about 30 min, or just change the seal..its cheep
the crank seal isnt behind the clutch, it is behind the gear that is attached to the crank shaft. U smoked the clutch because u ran it out of oil. maybe ur drain nut is leaking? maybe ur case halves are leaking? it would really run like sh*t if ur seal was leaking that bad..bog big time oil...
and if u are running a230 main and ur plug is soaked ur crank seal may be bad. (clutch side) can u tell if it is gas on the plug or oil? does it smoke like a mofo? like its burning oil? like a car with bad rings? and stink? i would say for sure ur jetting is off start with a new plug and a 300...
i have quite a few jet, u need to do a plug chop as stated. i think u will also need to move the clip on up needle..u can come out to irving and i will hook u up. on hers she has 3mm stroke fmf pipe stock carb and a 300 main..not sure of ur specs but if u tell all mods to motor can get u real...
if he added pipe and never rejetted thats a problem..u will also need a new needle..i have almost the same set up on one of ours..sounds a bit lean to me..on the main and pilot. u said he bored it new pipe and didnt change jets correct? stock carb i assume?
x 2 AND ALSO make sure all wires are connectd to the correct wire..if u took the flywheel of u could have sheared the key. i say check ground wire as stated