I am posting for a friend who is having trouble with fouling plugs on his yamaha venture. He is an older guy so i don't think he rides it too hard so i think most of the fuel is ran through the lower circuits of the carb. He says he goes out to ride and in the first 5 minutes he fouls a plug then changes to new ones then rides the rest of the day without any problems. Feedback would be appreciated. I do not know what jets he is running at the moment. Hotter plug? Smaller pilot jet? He says it runs fine after he changes the plugs once.

i would try a smaller jet first.

you could try a hotter plug that could be the prblem too.