need help!!banshee not running properly

[250R_SV]

Im helping a friend build a banshee, it is tunned properly and sounds good, but when riden, it does not runs as a banshee should (sorry for my grammar, Im from latin america!). I dont know if its because he has mixed parts: This is a 87 banshee with all the electrical parts from a 2003 model, it has 39mm carbs from a 250r, new gearbox from a 87 model, new clutch discs, fmf pipes and exhaust. I think the problem might be on the electrical part or somethinr conserning the carbs or pistons.
Need help, he's about to crack his head!!
comment appreciated!

[broke]

I'm going to venture a guess at the carbs being too big. The quad doesn't really care what year parts you put on it, Banshees didn't change much. You may have enough motor for those carbs, but it's a hell of a motor if you do. Let's here a little more about what it is or isn't doing.

[Dinner]

Those carbs are WAY to big for that engine

[firefighterjosh]

Originally posted by Dinner
Those carbs are WAY to big for that engine

^^ ^^ ^^

[250R_SV]

Hi guys. Sorry I didnt post anything more, too much work this days. Well we changed de carbs for a pair of oem we found, also the reeds and filter and the banshee is running as it is supposed to. thanks for your posts.