70cc upgrade - jetting issue ?

venxxxxx · 09-23-2013, 05:52 PM

Nevermind guys,
I put a 3/64 drill bit through the main jet and now its reaching 40mph.

Weird though, I was driving and all of a sudden it shut off. Scared me for a second, thought I blew a cylinder/piston. But I gave it a kick and it started right up again.

teddy554 · 09-23-2013, 11:42 PM

Quote:

Originally Posted by venxxxxx

Nevermind guys,
I put a 3/64 drill bit through the main jet and now its reaching 40mph.

Weird though, I was driving and all of a sudden it shut off. Scared me for a second, thought I blew a cylinder/piston. But I gave it a kick and it started right up again.

That is called soft seize but not only the shrouds but being lean not enough fuel will cause your motor to run hot.I about sure that running lean is the issue more then the shrouds

carasdad · 09-24-2013, 09:22 AM

Quote:

Originally Posted by venxxxxx

Nevermind guys,
I put a 3/64 drill bit through the main jet and now its reaching 40mph.

Weird though, I was driving and all of a sudden it shut off. Scared me for a second, thought I blew a cylinder/piston. But I gave it a kick and it started right up again.

Surprised it runs with a 3/64 drilled jet.. that equals 1.190 mm or a #120 jet!! Should be slobbering rich with that large a Jet...most 70 BBK's like a #85-#95 jet.