Air leak somewhere?

[splashcroft]

Hi all,
I have a 2017 300 RR, the last few times I have ridden my bike as the bike gets hot- halfway round a hare scramble lap the idle doubles in rpm and the bike runs really lean. I have changed air filter and took my bike to the local mechanic. He stripped and cleaned the carb, replaced intake rubber and reeds all looked good. The bike ran up to temperature fine.but still does it after riding. I can't seem to replicate the high idle without riding the bike.(it's off road only so can't). There is no obvious airleak, doesn't use water or engine oil. Could it be one of the crank seals? The bike runs and works fine otherwise. Any help would be much appreciated as beta is a bit exotic for my local bike shop. Nearest dealer is a long way

[dirtynenow]

Did you ever find a solution, the Beta I am trying to fix does the same thing but even worse, usually does it when warm on you are coming down on impact. I am removing the OI, I feel the issues is happening after the carb, the next thing I try will be crank seals but it doesn't use oil or smoke. The guy who owns the bike has crashed pretty bad do to the hang so is scared to ride it again until I am sure I solved it.