There are a few old posts about this. In very heavy rain, my bike (an 07 TA) started cutting out. If I open the petrol cap and close it, bike would start up and run fine for around 5km then same thing. If this is what is happening, cut the outlet of the vent hose at a 45 degree angle and around 2 inches shorter. If venting the tank does not provide 5kms of releif, (that is running fine) then it is something else and would start with the coils and grease.
