This is Mark Traylor (Tommy’s dad) we have been running birel at PKRA and I am trying to support other birel owners as much as possible. Go ahead and PM me and I will give you my phone number. I have a granite surface plate we can use to check the kart, put it on scales etc. I can also do a leak down on the engine and head for you and see if that is part of the problem. Also I know you don’t run every race so how old are your tires?