If I leave my 1985 R4 TL standing for a week or so, its quite hard to start, with no attempt to fire until the motor has turned over for at least 10-15 seconds (not done continuously). If I'm using it regularly, no problem at all, even after a couple of days. I spotted that after the 6-7 days standing period, the glass bowl on the fuel filter is empty. I assume its the fuel draining back into the tank but would have thought that the float chamber on the carb (rebuilt 32IF7 Zenith) would remain full. I'm thinking of installing a one way valve in the fuel line, am I missing something.......or perhaps just a measure of petulance for being left standing? Thanks in advance George