carb help

[blast off]

Hi guys, I have an 01 banshee that is pretty much stock besides FMF fatty pipes and silencers and K/N pods (oh yeah TORS kit too), I am having some running issues with it, the main jets that were in it were 310 which i think was too big so I put 280's in it and now it is running better than before but just not perfect, it seems to smoke evenly and run good when its revved over half throttle but down low it doesnt want to idle and the left side exhaust makes a popping noise here and there, I havent actually ridden the bike since i changed the jets because I am afraid something is wrong. I know for sure that everything inside each carb is exactly the same and at the same position but for some reason its just not idling and running right low end. I might be missing something so please dont be shy lol. I heard there a lot of cool and smart people on this forum so I was wondering if I could get some help here.

Thanks guys,

Eddie

[dajogejr]

Eddie,

First thing you need to to do is physically unplug the TORS. I promise they cause more headache than they're worth.

Unplug the wires going to the brain under your gas tank, tops of the carbs, clutch and throttle.

See if that fixes the cutting out problem.

 

The main jets have little to no effect on the low end unless they're WAY, WAY off...and I think you're ball park.

[blast off]

Eddie,

First thing you need to to do is physically unplug the TORS. I promise they cause more headache than they're worth.

Unplug the wires going to the brain under your gas tank, tops of the carbs, clutch and throttle.

See if that fixes the cutting out problem.

 

The main jets have little to no effect on the low end unless they're WAY, WAY off...and I think you're ball park.

 

Thanks for the fast reply dude. The TORS is removed, i have idle screws, sorry i might not have made that clear, I guess you thought that i have them on lol, Its no biggie. as for my mains yeah i think your right, im probably in a good range. I diddnt know the mains dont effect low end, that is good to know, thanks. any other suggestions?

[dajogejr]

Are all the wires disconnected as well, aside from the mechanical boxes that were on top the carbs?

 

I worked on an 01 that I had to cross the wires coming off the parking brake to close the loop.

 

Normally, if it runs good at mid and upper RPMs it's not electrical/spark related. Normally....

 

I would guess it's one of three problems, starting with the most unlikely

 

Slides in the wrong carbs, the half moon cutout must face the airbox.

Choke tube disconnected or sucking air, cracked, etc.

Carbs need to be sync'd. You can normally eyeball them pretty close. Jeff at FAST sells a tool that actually gets them dead on, it's called a syncrometer. It measures the vaccum pull at the carb. You set them at idle and again at about 1/3 throttle....and you're good to go.

 

 

What pilots are in the bike? What are the air screws at?

If you check the sync and it's good, remove the carbs, remove the bowls, remove the pilots and take a fine speaker wire and some brake clean and clean the pilots real good. They have tiny holes a grain of sand, literally...can plug. And that can quite easily cause cutting out at idle to 1/8 or 1/4 throttle or so....

 

Try this. Warm the bike up...then pull the chokes half way. It it runs much better, you have a fuel/jetting issue off the bottom (pilot and air screws). If it falls on it's face...and is blubbery...that's not the issue (again, check everything else out first...)

[FMF shee 98]

Are all the wires disconnected as well, aside from the mechanical boxes that were on top the carbs?

 

I worked on an 01 that I had to cross the wires coming off the parking brake to close the loop.

 

Normally, if it runs good at mid and upper RPMs it's not electrical/spark related. Normally....

 

I would guess it's one of three problems, starting with the most unlikely

 

Slides in the wrong carbs, the half moon cutout must face the airbox.

Choke tube disconnected or sucking air, cracked, etc.

Carbs need to be sync'd. You can normally eyeball them pretty close. Jeff at FAST sells a tool that actually gets them dead on, it's called a syncrometer. It measures the vaccum pull at the carb. You set them at idle and again at about 1/3 throttle....and you're good to go.

 

 

What pilots are in the bike? What are the air screws at?

If you check the sync and it's good, remove the carbs, remove the bowls, remove the pilots and take a fine speaker wire and some brake clean and clean the pilots real good. They have tiny holes a grain of sand, literally...can plug. And that can quite easily cause cutting out at idle to 1/8 or 1/4 throttle or so....

 

Try this. Warm the bike up...then pull the chokes half way. It it runs much better, you have a fuel/jetting issue off the bottom (pilot and air screws). If it falls on it's face...and is blubbery...that's not the issue (again, check everything else out first...)

 

im having a problem that my shee will only idle with the choke pulled out and if i press it in it will rev high and stall like its not gettin fuel

[blast off]

Are all the wires disconnected as well, aside from the mechanical boxes that were on top the carbs?

 

I worked on an 01 that I had to cross the wires coming off the parking brake to close the loop.

 

Normally, if it runs good at mid and upper RPMs it's not electrical/spark related. Normally....

 

I would guess it's one of three problems, starting with the most unlikely

 

Slides in the wrong carbs, the half moon cutout must face the airbox.

Choke tube disconnected or sucking air, cracked, etc.

Carbs need to be sync'd. You can normally eyeball them pretty close. Jeff at FAST sells a tool that actually gets them dead on, it's called a syncrometer. It measures the vaccum pull at the carb. You set them at idle and again at about 1/3 throttle....and you're good to go.

 

 

What pilots are in the bike? What are the air screws at?

If you check the sync and it's good, remove the carbs, remove the bowls, remove the pilots and take a fine speaker wire and some brake clean and clean the pilots real good. They have tiny holes a grain of sand, literally...can plug. And that can quite easily cause cutting out at idle to 1/8 or 1/4 throttle or so....

 

Try this. Warm the bike up...then pull the chokes half way. It it runs much better, you have a fuel/jetting issue off the bottom (pilot and air screws). If it falls on it's face...and is blubbery...that's not the issue (again, check everything else out first...)

 

 

Thanks man, Yes the wires are removed from the TORS. I tripple checked the slides and they are ok and i see the marks through the glass eye, the choke tube is good, i eyeball sync'd the carbs too but i'll double check that, I dont know what the Pilots are but i will remove them and check and clean them like you said too, and when i pull the choke halfway i think it runs better for the most part, i'll check that stuff out and get back as soon as I can.

Thanks a lot for all of your help, I appreciate it

Edited February 8, 2010 by blast off

[GrMeyer]

This will help you on jetting

 

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

[blast off]

This will help you on jetting

 

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

 

Thanks for the link, it helps a lot. I'll get back once i check the carbs out

[blast off]

Are all the wires disconnected as well, aside from the mechanical boxes that were on top the carbs?

 

I worked on an 01 that I had to cross the wires coming off the parking brake to close the loop.

 

Normally, if it runs good at mid and upper RPMs it's not electrical/spark related. Normally....

 

I would guess it's one of three problems, starting with the most unlikely

 

Slides in the wrong carbs, the half moon cutout must face the airbox.

Choke tube disconnected or sucking air, cracked, etc.

Carbs need to be sync'd. You can normally eyeball them pretty close. Jeff at FAST sells a tool that actually gets them dead on, it's called a syncrometer. It measures the vaccum pull at the carb. You set them at idle and again at about 1/3 throttle....and you're good to go.

 

 

What pilots are in the bike? What are the air screws at?

If you check the sync and it's good, remove the carbs, remove the bowls, remove the pilots and take a fine speaker wire and some brake clean and clean the pilots real good. They have tiny holes a grain of sand, literally...can plug. And that can quite easily cause cutting out at idle to 1/8 or 1/4 throttle or so....

 

Try this. Warm the bike up...then pull the chokes half way. It it runs much better, you have a fuel/jetting issue off the bottom (pilot and air screws). If it falls on it's face...and is blubbery...that's not the issue (again, check everything else out first...)

[blast off]

Hi dajogejr, I removed the pilots and the number on them is 25. They weren't very dirty but I'm gonna clean them and the ports out anyways. Do u think the pilot is small?

Thanks,

[dajogejr]

With FMF pipes and Pod filters? Yes.

25 is stock.

FMF pipes generally like a fatter pilot.

Is it really cold where you ride? Like...50 degrees or colder?

What is your altitude?

 

One step up from stock is 27.5, the next is 30.

At the very least, I would buy a pair of 27.5 pilots for that bike, turn the air screws out 1.5 turns from lightly seated...and try it again.

 

If you had an airbox with no lid, I'd try the 25 pilots and turning the air screw in.

With pods...I'd go richer.

[blast off]

yeah im in NJ and its 32 degrees and snowing lol. Im gonna have to get those pilots tomorrow and try it. I will get back once i do it.

Thanks for all of your help

[blast off]

Hi Guys,

I know that im SUUUUUUUUUUUUUUUUUUPER LATE with this but I just wanted to thank you all for your help. I was In FL visiting my old man so I diddnt have time to mess with the bike until now. SOOOOOOOOOOOOOO, I took the carbs back off and disassembled them just to tripple check and guess what! I had 1 of the stupid slides on wrong WOMP WOMP! Im a moron, "my bro prob sabatoged it when I wasnt lookin" lol. So I fixed that and put 280 mains in it and 27.5 pilots and the thing runs like a raped ape! Thanks again for all the help. I CAN RIDE NOW!