Jetting Help in Missouri---Ready to light a match to it

[banshee2007]

OK first of the banshee is bored 20 over and has stock style cast pistons in it, stock porting, vitos 2 stage carbon reeds, reed spacer kit, stock carbs with tors, pro design cool head, open airbox with k&n filter and outerwear. i use klotz 2 ctroke benol oil mixed 16 ounces to 5 gallons.

 

 

I have a vitos jet kit installed--using vitos needles, clip in middle, 310 mains, 27.5 pilots, airscrews 2 turns out---in neutral from idle to 3/4 it revs great and sounds very responsive---3/4 throttle and above it will sometimes backfire and blow flames out right side silencer, or it will pop..

 

when going down the road and speed shifting with throttle at full position it is loaded up and wont clean out---just bogs through the gears--goes faster in each gear but will not clean out at all to rev like they should.. runs like crap..

 

i have checked the intakes and found 2 leaky gaskets, i replaced those and didnt find where i had any bad intakes themselves, everyone was telling me i needed between 310-330 mains in it to run right---When i had 290s in it the quad ran better on the high end than it does now but it still backfired on high rpm only-----I have never had this much trouble ever jetting a banshee and getting one on right---This one has had me ready to light a match to it..

 

With the 330 and 310 jets i did plug checks and found the plugs to be dark brown to blackish color---that would be rich to me---but people say with the popping and backfire that means to lean---im not finding lean with my plug checks

 

Does anyone here in the columbia, missouri area have any advice on what could be going wrong here.. Should i go down lower than 290s in the mains or what???

[shee4speed]

if the 310's are rich and boggy,then put the smaller jets back in. I wonder if your reeds are jacked.

[banshee2007]

brand new reeds and double checked for proper installation. i just bought this banshee 3 weeks ago and rebuilt it.. i did find that the caarb bowls were not on the right way, they were mixed up and can only go one way from what i have read so far. out of all the banshees i have had in past i have never tuned one with factory carbs. all my others were highly built and very easy to tune this one is a damn bear

[BansheeJohn]

brand new reeds and double checked for proper installation. i just bought this banshee 3 weeks ago and rebuilt it.. i did find that the caarb bowls were not on the right way, they were mixed up and can only go one way from what i have read so far. out of all the banshees i have had in past i have never tuned one with factory carbs. all my others were highly built and very easy to tune this one is a damn bear

 

 

I have a set of stock carbs bored to 28's w/tors removal updated needle I'll sell ya for $150 shipped.

[shee4speed]

I dont think he needs new carbs. Have you checked the plug caps? Is it backfiring on both sides?

[banshee2007]

nah just one side has been back firing.

[rtcc]

well if one side has been backfiring most likely its not the jetting, probably an air leak or a dirty jet. Put the 290's back in and do a proper plug chop. Go from there.

Do you have stock pipes? If so 290's should be fine.

My bike was still using the stock pilots when I had stock carbs, even with all the mods I have now. I would put the stock pilots in and see if it is messing the plugs up early. Then if that is better check the needle. I dont know anything about the vito's kit but you dont have that many mods so it might be overkill.

 

Also, man right now Im sure you are noticing the weather is completely out of control. If you jetted in 70 degrees and you take it out today (31 where I am) then it is gonna be lean.

[banshee2007]

yeah i know this weather is making it hard to do jetting, i am gonna wait till later in week to try again.. i work yesterday on it and tried several ways. stock pilots-stock needles--290, 300, 310 jets no good---went back to vitos needles, 30 pilots--and 330 jets--needles set on 3rd position--banshee is very responsive from idle to 3/4 throttle, and from 3/4 to high rev it just isnt there yet--back firing has pretty much went away.. i have double checked everything there is no leaks that i can find anywhere.. im now starting to wonder if my left side spark plug boot may be bad.. that is the side i am having problem with.. jets are all clean in carb---the guy who owned it before me had the carb bowls backwards, when i corrected that yesterday it started to run better..

[nameehsnab]

Also look for an exhaust leak