My friend is in the process of breaking in his new ofna hyper 7 with the .21 engine. The buggy ran fine untill the second tank or so.

the buggy now runs great for about a minute or so and then it develops a high idle and shuts off when throttle is applied. The engine is running around 200-220 degrees. We know it must be a tuning problem but we do not know why it develops a high idle after it has been running for a while.

ANY IDEAS WILL BE V ERY APPRECIATED.

So it gets a high idle and dies? Sounds like it is running out of fuel or maybe a airleak. You know when you your buggy is idling and you pinch off the fuel line to shut if off that way, right before it dies the idle raises back up. Check for air bubbles in the fuel lines or a pinched line some. Also do not over look your glow plug. Break ins are hard on them and could be going bad.

I innitially thought it was an airleak because it is very hard to get gas to the carb while priming with the muffler. There are also many bubbles in the fiel line but once it starts up the bubles go away. The buggy starts up and runs great but after a minute or so the high idle happens and shuts off as soon as throttle is applied.

I did a search and maybee the LSN is lean and that is causing the high idle after a minute or so. Opinoins?

If the LSN is turned too far in I think if might cause that. It could be just running on the fuel you force in the carb if blowing it in. Someone correct me if I am wrong but maybe. Just turn out the LSN 1 or 1.5 turns just to see what happens. If it still does it try 2, if not that put it back to where it was so you do not lose your setting and try something else.

Sounds reasonable. I've had my buggy stall before when I gave it throttle simply because it was too lean.

lsn is to leen