Tired 206??

[Outrider]

We used to keep old spark plugs around to break up the insulator and use the metal body to make adapters for leak-down testing, back when different diameter plugs (other than the 2 common diameters of the time) first started showing up. Sounds like that's still a good idea - I'll have to check, now that you brought it up; I'm not sure that my leakdown test rig has a 10mm adaptor either.

 

[Flash-o-matic]

10 mm adapters are not very easy to find. Easy to make from used spark plugs. Or new spark plugs if you're a high roller. Ha!

 

[screamn 2]

Yeah....but the 'trick' is in making one that doesn't 'Leak'! LOL

 

[oldman50]

A guy I race with had this problem too. Apparently something with the compression release messed up the lifter/cam lobe. Check the lift height on your exhaust valve, that was the only sign of issue with his motor. Briggs replaced everything since it was a compression release issue.

I have had a problem with the compression release since the 2nd or 3rd race. Talked to Briggs about it but never got a new motor. It is still that way and I am almost afraid to use the motor, afraid the rope will break on the grid. With no one in the kart you can lift it off the ground.

Yes we have adjusted the valve lash several times.