I don't know much about the carb models other than what I have picked up online. I think the stock main jet is a 510. D&D recommends a 510 with their monster twins I believe. Some guys have been running 500 and 490s and having good results. Be sure to check what size main you have before you just slap the pipe on. A lot of the carb F7 owners had installed 470 mains, and 30 pilots (Stock is 35) to get rid of the bog off the line. If you bought the sled used don't expect it to be totally stock I guess.
I hate to steer new guys away from this site, but there just aren't many F7 owner here, especially ones with carbed F7s. Try ArcticChat.Com for some better responses.
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