No I haven't got a round to buy a comp tester. You think I should now that it fires up?

 

Yes...low compression engines will fire up and even run under part throttle, but under full load the expansion from heat creates an environment where combustion can no longer take place...and they die. I thought that was a condition you were experiencing?

 

Aaah I see. I haven't got to try full throttle. Just started it up in the garage tonight. I'll get my self a tester and see. What value should it have if it's "good"?

 

LT80 may over-rule me here but I'd say:
100psi = livable
110 - 120psi = good
120+ = Ye Ha!


Mine pulled a 130 on a stock motor when I picked it up for reference...

 

90 minimum.
Borrow a gauge from autozone/etc.

 

Did the compression test this morning. 150 psi should be ok, right?

 

hehe..It's fine. I didn't expect that much.

 

It seems to run just fine now. The only issue I have left is that I have adjusted the throttlestop on the handlebar so they won't drive so fast and doesn't run clean at first. But when they have driven 50-100 meters you really hear that twostroke-sound. Shall I lower the needle some?

 

Do you know how to read a spark plug?

 

Can't say I do. Enlighten me?