fouling plugs, jetting confusion

[humbleslc]

kinda stumped with my jetting.

260 mains

stock pilots 2 turns out

pro circuit pipes and silencers

air box with a couple holes K&N filter

 

It runs great once it gets moving, but down low it feels like it's bogging, which confuses me since the stock pilot jets are in it. I feel like i should move to the next biggest size, because the more i turn out the screw the better it runs, yet i am fouling plugs like crazy, which makes me think i should lean it out down low. i am lost any insight? (fouling plugs like 4 fouled plugs in 5 hours of ride time) also running Klotz R50 with 93 octane 32:1

Also i cleaned both carbs about twice already, no help.

[csrmel]

banshee carbs have pilot jets for low throttle openings. its the opposite of a typical adjustable idle jet on a car or weedwacker. on a typical idle jet weedwacker card, clockwise leans it out and couter richens it.

 

on a banshee, as well as most dirtbikes and stuff, clockwise richens the idle, counter leans it out. the more you turn the screw out the better it runs is because its leaning out. probably bogging from being so lean. try run it at 1.5 turns out and see what happens to the bog.

 

whats youre needles set at?

something is wrong because you shouldnt be fouling out with those jets and pipes.

[humbleslc]

banshee carbs have pilot jets for low throttle openings. its the opposite of a typical adjustable idle jet on a car or weedwacker. on a typical idle jet weedwacker card, clockwise leans it out and couter richens it.

 

on a banshee, as well as most dirtbikes and stuff, clockwise richens the idle, counter leans it out. the more you turn the screw out the better it runs is because its leaning out. probably bogging from being so lean. try run it at 1.5 turns out and see what happens to the bog.

 

whats youre needles set at?

something is wrong because you shouldnt be fouling out with those jets and pipes.

forgot about the needle, it is 2 down from the blunt end

I understand that the more turns out it leans it out, i ran it at 1.5 turns but the bogging gets worse. when i let it idle and check my plugs they are pretty wet. when i check my plugs after a WOT run they look good, a tan color. so i figure my main jets are pretty dialed in. This jetting is just really frustrating me

[humbleslc]

would a hotter plug do any good without melting my piston, or changing oil maybe?

[dajogejr]

I would make sure your choke circuit isn't plugged open, etc...

It's surely not going to hurt if you throw a larger pilot in, odd that you'd need it with an airbox and lid still...though.

But that goes to show you, each bike is different...

 

Actually...csr...you're on the right track.

 

For low speed circuits on carbs, there's either an air screw or a fuel screw.

 

If the screw is behind the slides, it is an air screw...turning it out gives more air, in less air.

If the screw is in front of the slide, it's a fuel screw...turning it out gives more fuel, in less fuel.

 

Turning the screw clockwise will always give you more, air or fuel, depending where on the carb it is....

 

Turn your air screw 3.0 then 3.5 turns out. If it runs better, put bigger pilots in. I think the usable range on the air screw is 3 or 3.5 turns out...might be less.

Put bigger pilots in ...start with 1 turn out.

 

What are you gapping your plugs at...by the way? You shouldn't need a hotter plug....

 

Also, is your air filter cleaned and/or oiled properly? An over oiled or dirty air filter richens things up too....