Jetting Question

[Cali]

I have a 2000 Banshee.When I got it, it was blown up left cyclinder sized.So I bored them to 020 and rebuilt engine.It had 290 mains and stock low speed jets.I have t5 exhaust with mild port work.Other than that stock.So removed tors and went 340 mains and kept low speed same.It would idle fine and ran good.Did seem to be a bit boggy when you first took off giving it a litle bit of gas.Kinda acted like it wanted to die.Adjusting air screw did not change anything.I have stock air box,with snorkle removed.So I droped it down to 320 mains and still stock low speed.The needle is in the middle postion.Now its worse.It will not idle at all, and air screws make no diff, when adjusted.Seems to run about the same on top.But wants to die once you back off the throttle.My altitude here in Bakersfield Ca is about 350ft.I ride mostly at Pismo.So my question is should I go back to the 340s or maybe try 330s?What about the needle?Should I move it up?I was told by another person I need 30 low speeds,but that seems over kill.Thanks for any advice you guys can give.

[T_Shee]

i would try some 27.5 pilot jets at least. start by doing some wot plug chops to get your main jet dialed in. that is the most important thing so that your not lean and hurting the topend. then work on getting it to idle correctly and good midrange is mostly a matter of adjustments (after you change the pilots) set your idle screws up a bit to make the bike idle, then mess with your air screws to make it nice and crisp (should be around 1 to 2.5 turns out or so). then you can change your needle clip position if you need to make the midrange feel right. most importantly tho make sure the carbs are syncronized meaning both slides come up at exactly the same time

[Cali]

i would try some 27.5 pilot jets at least. start by doing some wot plug chops to get your main jet dialed in. that is the most important thing so that your not lean and hurting the topend. then work on getting it to idle correctly and good midrange is mostly a matter of adjustments (after you change the pilots) set your idle screws up a bit to make the bike idle, then mess with your air screws to make it nice and crisp (should be around 1 to 2.5 turns out or so). then you can change your needle clip position if you need to make the midrange feel right. most importantly tho make sure the carbs are syncronized meaning both slides come up at exactly the same time

 

Ok whats stock 25 pilots?Mine are 27.5 already..I have the syncronized also.Thanks for the info

[firebanshee]

I run 27.5 pilots and 330 mains with pod filters,middle clip on the needle and 2 turns on air screw and t-5s at sea level on one of my bikes, so you should be leaner with your air box and lid on. Probably around 290 main.

 

25 is stock size for pilot

Edited February 7, 2010 by firebanshee

[GrMeyer]

How did you sync the carbs? by eye? I have learned that it will get you close, but it is still off. The best way to sync carbs is with the air meter gauge. Around $35. So I would invest in that. Because when you pull the carb tops to change the needle height that they can come un synced with the tors. So the best bet is to get the TORS kit if you dont have one because it will save you time.

 

Also read up on this site

 

http://www.dfn.com/benkaren/jetfaq.html