I brought the bike into a shop here in DC to have the front tire replaced. I asked them to look at the petcock and they said it was fine. They also said running it in prime would have a negligible effect on mpg.
However, from my calculations, I am getting at best 20mpg when running in prime. Meanwhile, the last few weeks I was running on RES, I was getting about 53mpg!
Thanks for the welcome! I've actually been trying to signup for months but kept getting an error message. Glad to finally get in!
Savage_Rob wrote on 02/21/12 at 16:09:26:Welcome to one of the best sites on the web, especially of you ride a Savage. I'm not sure what the cutting out issue is but if setting the petcock to prime "cures" it, I'd definitely pull the petcock and check it out. It may have some crap stuck in it. Using prime over run should make no difference to mileage since it simply taps your tank at a lower point. Hmm, I don't think it requires vacuum for prime either. That said, you may have a vacuum issue.