Good afternoon everyone. I'm having a problem with an engine. I bought a super tigre g51. Now, I've been trying to tune it since last fall. My problem is, I get a good idle and and good response, but when I take it up to w.o.t. it runs for maybe 5 seconds, then dies on me. This happens almost every time. Once in a while it'll bog down and let me back off the throttle and recover it without it shutting off. I've tried two different plugs. A long plug with an idle bar, not sure of the make. A guy at the field gave it to me and told me to give it a try, and an OS8. One other thing, no matter how tight I make it, the exhaust leaks. Could that be the problem? Could it be at full throttle, there isn't enough pressure to push enough fuel to the carb? If so, how can I seal it up? Is there an oring I need? Thanks for any help.