So I haven't ridden my banshee since last summer (08), and I bought some Toomey TR-6's about a month ago, just now getting around to installing them...

Shee's always run just fine, probably doesn't have more than 100 hours on her, but the last few rides something wasn't quite right. Didn't have a stable idle, and even after a proper warm-up, I couldn't hold a throttle position without bogging. Then when I went to fire up most recently, she only ran on the left cyl. So I tore apart the carbs, cleaned everything out, fresh fuel, fresh plugs, air filter, tuned idle and air-fuel screws, all good, right?

Well now the idle is stable, a bit high to my ear but fine, air-fuel is spot on, and both cylinders are firing. However, when I say idle is stable, I mean only on half-choke. At half choke in fact, she runs like she should with NO choke. So with no choke, she... well she sputters and stalls. Played around with the idle and air-fuel to no avail. I'm not perfectly clear on the mechanics of the shared choke, or whether I put things together just a little off, but any advice would be appreciated. I'm sure it's something minor, but I can't quite figure it out.

Keep in mind this is all pre-toomey's, everything is still bone-stock. Technically it doesn't make much difference since I'm going to tear it all apart again to install the pipes, but I just wanted to make sure everything still runs right and I don't have a bigger problem.

 

Anybody? C'mon I need some help here.

 

Im no mechanic but I mess around with quads and dirtbikes as a hobby, and own several myself, including a banshee. Normally when you have to have something partly choked for it to run right, that means one of your jets is plugged. I know you stated you pulled the carbs apart and cleaned them, but did you remove the jets and clean them?? I would double check them. And if you cant see thru them, use a welding tip cleaner to open them up. If that fails, jets are usually only 3 or 4 bucks a piece.. its alot easier to just buy new. Be sure to bring the old jets with, so that you get the right ones.. Hope this helps

 

I have so far disassembled and reassembled both carbs twice, and yes that includes cleaning the jets. Only thing I haven't done, and I don't know how much of a difference it makes, is tweak the floats back to factory spec. They've never been touched before this, so they shouldn't be off, unless they were jarred or vibed out of spec during riding.

I thought that when the right cyl. was firing again, that indicated the jet was unobstructed. But, since I can't think of much else, I'll try again. Can't hurt, right?

 

first to sync carbs you should have a air pull tool but ill give you my cheater method works great for me...
first off you choke plunger are out of sync from what you said...or sticking
pull plungers and make sure they move free up and down with a pair of needle nose plyers.... i clean them with a scotch brite pad and lube them with 2 stroke oil
after you got all that ok... you will have to set them up....
put the choke on full and then with you fingers draw up the threads untill you feel it starting to tighten up with that grab the cable and give it a pull up to see if you got all the play out...this should when turned off drop the plugers down...
with the choke off your cables should be relaxed with no tension in the plugers....then lock the nut
now with that done you will have to sync the carbs themselves heres how i do it with out a gauge////
loosen off the slide jam nut and lube them up so they will turn easy with your fingers.... now back out the idle screw so it almost fall out or take it out your call...
get yourself a small socket to fit between the slide and the base of the carb...so it only lifts the slide slightly about a 1/8 of a inch max....
using your fingers screw the slide nut in/out untill it just touches the socket repeat on second carb...
now put you finger in the carb and squeeze the throttle intill your finger and slided hit the top edge of the carb are they the same height if not tweek them so they are the same...
now check your jet screw set to 1-1/4 to 1-1/2 turns out complete turn most people mess this up by not completing a full 360 turn out...then the 1/2 turn...
now put in you idle screws untill they just hit the slide....
now when you start it you will have to play with the throttle untill you get it warmed up enough to adjust the idle.....
hope this helps......
go for a rip you should have good throttle responce...
bring a screw driver to adjust jet if needed...

 

sounds like you need to thoroughly disassemble and clean every part in the carbs then maybe sync you carbs with a carb sync tool, you can get them at farmandsandtoys.com every banshee owner should have one there awesome, also you installed toomeys but didnt step up your main jet sizes at all?

 

I'll look into that sync tool, I keep hearing about them so I should just get one.

Not sure how much more thoroughly I can clean the carbs though, (haven't done the 3rd cleaning yet), and I completely disassembled them, cleaned all parts with gas, compressed-air dried, reassembled, etc...

Also, like I said, the Toomey's are still in a box, this is all before attempting to install them.

 

If you have any further questions about your shee, create an account on BansheeHQ - Home. The guys on there really know what they are talking about.

 

Funny you should mention it, I'm writing a post on their forum right now. Does look to be a knowledgeable community.

Thanks for all the input guys, I'll get this sorted out before long.

 

hey i have a banshee its a 2001, ported,twin race carbs,k&n filter with air box lid filter , and full fmf pipes.. i bought it about a month ago and it always reved really high at iddle but once its warmed its got a lower idle speed, most recently the problem is when you rev it up only one cylender revs qnd the other sort of spyters and iddles im not sure whats whrong thanks for the help.