Hello billj, I used Ron Gardner carbs for a time, Just sold a pair, Ron is still active, But his son has taken over so I am told. Ron told me many years ago to always use float chambers, But i was going for top speed, Sprinting in the road class and riding on the road and had trouble with carbs passing petrol, So just had a pipe out of the tank to the carb,Only trouble was that a full tank was a click richer than a low tank.There are many needles you can buy and you must turn the needle till it goes click i.e. A full turn, In for weak Out for rich. I had a lot of fun with them but found them a bit messy, Because of how they worked there was always petrol leakage, I don't think they are very good for the road, Slow running is not the best, But if you do a lot of fast work they may be OK. Good Luck Bill.