Insufficient fuel cause uncontrallable RPM rise????

[I_Duddits]

Further to my throttle snap shut thread.....

Does this seem likely to anyone?

I'm wondering, the carb (I think) is bigger than std ie: 38mm not 36mm, is it possible then that she's running out of fuel? Would that cause the increase in uncontrolable RPM?
It fits then that the bike behaves ok stationary but screams after a run due to fuel demand. How could I tell (while riding) if the bowl remained constantle full?

I'm clutching at straws here, does any of this follow logically?

[Hillclimb#42]

Any lean-out condition will cause it to go crazy. Start at the beginning. Check petcock flow, then fuel line, then float adjustment, jets ect. Could be leaking head or base gasket. There is plenty of thing it could be. If it just started doing it, look for plugged petcock or debris in tank or jets. Old problem is probably floats need set properly. Could also be that the slide is not returning to a closed position. Other real experts would know about the size of carb issue. Good luck with it.

[maddoggy]

you may want to check your carb to cylinder rubber adapter. mine was severely weather cracked and i just caught it in time before it caused me any trouble. if it had cracked all the way through it would have caused the exact symptoms you're describing. if it's ok then hillclimb#42 headed you in the right direction. start with the basics and work your way through the engine.  MADDOGGY

[I_Duddits]

All suggestions "seem" to me at least to be geared toward the ingress of air causing it to run lean. I'm suggesting it might be too little fuel. One and the same thing ultimately but is too much air (gaskets, seals etc) more likely than too little fuel?
I'll have the carb off again this weekend, I'd still like to know if the bowl is maintaining level during a run or if demand exceeds supply causing it to run lean.
I'll try spraying areas with ether to see if it's sucking air anywhere.