Dunsmoor86 Posted July 5, 2005 Report Posted July 5, 2005 (edited) I have the following mods: Timing +6 FMF Fattys Milled Head .30 Boysen Reeds K&N (in the airbox) Stage 2 porting (more than mx but not drag port) .40 over pro-lites No airbox lid Stock reeds are ported a-little I'm currenlty running 320 mains and 32 pilots on the fourth maybe third clip. My bottom end has a sputter not just a banshee bog, my top end seems to run alright seems like it could be bette, and my air screws are 1 turn out. My plugs are light brown. Any info would be very helpful thanks alot. Edited July 5, 2005 by Dunsmoor86 Quote
Rare Scottish Tree Badger Posted July 5, 2005 Report Posted July 5, 2005 You're pilots seem a bit big. I'm similar to your set up (@ 660ft.) and I've screwed my motor twice at full throttle 300 mains. ... On this rebuild I'll be trying 380 and coming down from there. What height above sea level are you? You should do a plug chop. I think you could go up at least a couple of sizes on your mains if not more. Especially with +6 advance, but I'm hardly the right guy to listen to right now . Rare. Quote
Dunsmoor86 Posted July 5, 2005 Author Report Posted July 5, 2005 I'm at around 700ft elevation so im sure we are the same there. I have ran 340 mains and it seemed to run a bit cooler but not much faster. Quote
fastbanshee4u Posted July 5, 2005 Report Posted July 5, 2005 Go back to 30 pilots and your mains could be small .A good ported banshee can take up to 400mains no problem. Put your air lid back on and if it seems to run faster then you are lean. Quote
Banshee~ Posted July 6, 2005 Report Posted July 6, 2005 Who ported your engine? They can get you in the ball park, but I wouldent run anything under a 360 main with the lid off. Try what fastbanshee4u said, put the lid on, and that will make you 1-2 main jet sizes bigger so you can tell about were you are. Quote
cbn70 Posted July 6, 2005 Report Posted July 6, 2005 I know it is a bit hard to do, but try to pull on the choke when you are wondering about your jetting. It will tell you right away if you are rich or lean. If you pull on the choke and and it runs better, you are lean. If you pull it on and the moter starts to sputter and die then it is rich. hope this helps Quote
Dunsmoor86 Posted July 6, 2005 Author Report Posted July 6, 2005 Well i went to the Yamaha shop today and he said he thought i was rich? So i went down to a 300 main and did a plug chop than he said i was a bit lean and to go back to 320 mains so i did. I ended up with a somewhat light ring around the bottom of the plug and it seemed to run good to me. So i guess im set. P.S. I did try the choke thing and it seemed to run worse with the choke out. Thanks Quote
Rare Scottish Tree Badger Posted July 6, 2005 Report Posted July 6, 2005 I ended up with a somewhat light ring ... That's what you started at . ... Why haven't you tried going richer on the mains? Quote: "My bottom end has a sputter" ... What did he say about your pilots? Rare. Quote
cbn70 Posted July 6, 2005 Report Posted July 6, 2005 If it ran worse with the choke out then I would say that you are on the rich side of things Quote
Rare Scottish Tree Badger Posted July 7, 2005 Report Posted July 7, 2005 If it ran worse with the choke out then I would say that you are on the rich side of things 389498[/snapback] Fair point, but it depends what range he was in when he did the choke trick. EDIT: The symptoms showed rich at lower throttle, so pulling the choke in that range would only make matters worse. ... And unless it was pulled at WOT (dodgy maneuver) the effect on the mains wouldn't be noticed. Rare. Quote
Dunsmoor86 Posted July 7, 2005 Author Report Posted July 7, 2005 I put my needle from the middle clip down to the fourh and put my airsrews at .5 and they are 27.5 now with 320 mains and it seems to be running pretty good. I would have tryed the 340 mains but i lost one and the Yamaha dealer doesnt carey them that big. At first he thought i should be around a 280 main and couldnt believe that i was up that high in jetting. He said i was so rich that it was washing the plugs off with fuel. And then i showed him he was way off when i tried 300 mains and it was pretty lean. Im almost thinking of just taking the damn thing to a dyno. Quote
Banshee~ Posted July 7, 2005 Report Posted July 7, 2005 I put my needle from the middle clip down to the fourh and put my airsrews at .5 and they are 27.5 now with 320 mains and it seems to be running pretty good. I would have tryed the 340 mains but i lost one and the Yamaha dealer doesnt carey them that big. At first he thought i should be around a 280 main and couldnt believe that i was up that high in jetting. He said i was so rich that it was washing the plugs off with fuel. And then i showed him he was way off when i tried 300 mains and it was pretty lean. Im almost thinking of just taking the damn thing to a dyno. 389607[/snapback] Your going to blow your engine if you run it long with 320 mains. Im at the same elevation with pipes,filter, and the lid of and im running 320 mains. Order main jet sizes 340-380 and start with the 380's, if it bogs at WOT try 370 mains(continue until it doesnt bog). Once you dial in the mains, work your way down. I would try 30 pilots. Quote
Dunsmoor86 Posted July 8, 2005 Author Report Posted July 8, 2005 I have been running 320 mains for about a year now with no problems but i will wait till i get some money since i am broke and get 340-380 mains and 30 piolts. If it runs the best with my air srews all the way in does that mean i should jump up to the next piolts being 30? Quote
Rare Scottish Tree Badger Posted July 8, 2005 Report Posted July 8, 2005 If it runs the best with my air srews all the way in does that mean i should jump up to the next piolts being 30? 389914[/snapback] yip. Rare. Quote
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