kb247 Posted December 22, 2006 Report Posted December 22, 2006 I have an 87 banshee with FMF fatty pipes,power core II sileners, bored .60 over wiseco pistons stock carbs and everything else pretty much stock. I recently obtained this precious machine about four months ago, it was in Colorado and I am in Louisiana, so i had to tune it for here. Now when I got it it ran ok but compression was low so i tore it down and did a top end overhall and re sealed the entire motor. ran good when i put it back together but i noticed that it had 210 mains in it, so i know that is way to lean for here so i got new jets for it. I installed 290 mains, (was trying to start out a bit rich and go from there) and 30 pilots, and also changed the needle which was put on the third or middle notch. When I fired it up for the first time I noticed that the left cylinder was not firing ( it would fire maybe 1 time in a 5 second period) the right was firing good. So next I put in a set of new plugs which I should have done anyway, since this the left is still not firing correctly. It has improved but it still is not firing like it is supposed to. Now I've checked the obvious things like wiring and things. I did check to make sure it has fire and it does have a good spark. I guess the next thing to do would be tear the carbs down again and double check evrything and check the reeds. I'm just hoping some of you Banshee Gods could give me a little something more to go on. You guys have been such a huge help since I started this project!! Quote
kb247 Posted December 30, 2006 Author Report Posted December 30, 2006 I have an 87 banshee with FMF fatty pipes,power core II sileners, bored .60 over wiseco pistons stock carbs and everything else pretty much stock. I recently obtained this precious machine about four months ago, it was in Colorado and I am in Louisiana, so i had to tune it for here. Now when I got it it ran ok but compression was low so i tore it down and did a top end overhall and re sealed the entire motor. ran good when i put it back together but i noticed that it had 210 mains in it, so i know that is way to lean for here so i got new jets for it. I installed 290 mains, (was trying to start out a bit rich and go from there) and 30 pilots, and also changed the needle which was put on the third or middle notch. When I fired it up for the first time I noticed that the left cylinder was not firing ( it would fire maybe 1 time in a 5 second period) the right was firing good. So next I put in a set of new plugs which I should have done anyway, since this the left is still not firing correctly. It has improved but it still is not firing like it is supposed to. Now I've checked the obvious things like wiring and things. I did check to make sure it has fire and it does have a good spark. I guess the next thing to do would be tear the carbs down again and double check evrything and check the reeds. I'm just hoping some of you Banshee Gods could give me a little something more to go on. You guys have been such a huge help since I started this project!! well i tore the carbs down again and everything looked ok, so i went down to a 270 main jet and the problem corrected. now i just have to adjust the carbs correctly and i think i'll have it. Quote
bansheesmoke Posted January 6, 2007 Report Posted January 6, 2007 well i tore the carbs down again and everything looked ok, so i went down to a 270 main jet and the problem corrected. now i just have to adjust the carbs correctly and i think i'll have it. I was gonna ask about the carb crossover tube. and with Just pipes and .60 bore i dont think you have to change the pilot jet. Quote
dajogejr Posted January 6, 2007 Report Posted January 6, 2007 I agree...especially if you're still running the stock airbox and lid. If you remove the lid and put an aftermarket filter in, maybe 27.5....but you won't need 30's unless you completely remove the airbox, even then it's iffy... you can always switch spark plug leads from the coil to see if it follows the plug wire. Changing the main jet should have no effect on if the cylinder hits on idle/startup or not. I'd go completely through each carb, one at a time to make sure there is no gunk and the float are set correctly!! Quote
Fastrat Posted January 6, 2007 Report Posted January 6, 2007 I'd also do a leakdown if you haven't and make sure there's no air leak leaning it out. GL Quote
kb247 Posted January 6, 2007 Author Report Posted January 6, 2007 O.K. I did forget to mention that I have removed the lid from the air box and I have an aftermarket filter. Since posting this I have tore the carbs completly down and cleaned them leaving the 30 pilots and the 270 mains. at full throttle the bike runs great screaming through all 6 gears, but low range rpm's like idle through say 1/2 throttle in runs rough, however both cylinders are firing great that problem is now gone.The only reason I went with the 30 pilots and 290 mains was because thats what the guy at Vito's told me would work best with what I have. Now that my mains are good I think I will try going to a 27.5 pilots like you guys are saying to and I have also ordered a carb sync tool from F.A.S.T. ( These guys seem to be very helpfull and know their stuff about the almighty banshees). Let me know what you guys think!! and thanks for all of your input once again you guys are great! Quote
Fastrat Posted January 7, 2007 Report Posted January 7, 2007 Since most of the problems have cleared up, I'd say you're on the right track Quote
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