if i take off my airbox lid and it runs better, does that mean that the jetting is better with the lid off and i dont need to rejet? or should i still rejet the carbs?
quick little jetting question
- Thread starter NOVIS
- Start date
You should still do a plug chop at least. It might run better because it was too rich (and now is perfect) or maybe it is too lean now (past perfect), engines like to run lean (until they blow up).
Jet accordingly.
Jet accordingly.
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A little lean will make it run better (for a short time) TOO lean and it won't run well at all. I'd rather be a little rich than any of the other choices.
If it was running too rich and you removed the airbox lid, it's probably a little on the lean side which will make it run great but short lived.
....................What else has been done to the motor? If it's completely stock and you just took off the lid, then it's almost certainly running lean now. If it has already been rejetted for an aftermarket pipe but had no modifications to the stock intake and filter, then you're probably safe since removing the lid probably just balanced the free flowing exhaust and the bigger main jet. There are a dozen different modifications that can lean out or richen the mixture, so much so that it's near impossible to come up with a formula for the right jetting. The best advice on jetting comes from your spark plug, it'll let you know whether you're lean or rich and then you can decide where to go from there. If you're not sure what a spark plug will look like under lean or rich conditions just check Google images, or in the back cover of most automotive service manuals. I'm with the other guys on running a little rich rather than a little lean, I'd rather be cleaning a gummed up spark arrestor and a fouled plug than pulling the jug for a top end. Good Luck!
well i havent even tried it yet. i was just wondering because i was gonna test it out when i get some gas. i have stated it and its a hell of alot louder. its its for my banshee in my sig, i know about running rich and lean and all that crap ive and i know how to jet according to all the stuff and more air= more fuel. i would normally just rejet for the airbox lid but i thought if maybe it ran better that i wouldnt have to rejet. my banshee has fmf pipes, K&N filter, white bros boost bottle (not sure if it really does anything). and some other little things. not sure what jets are in there cuz i got it like this.
Its always better to be richer than lean. Your plug should be a little darker than cardboard color. The darker and closer to black it is, the richer it is. The lighter and closer to white it is, the leaner it is.
Just get the bike warmed up then kill it and put a new plug in. Restart it and ride hard for 15 to 20 minutes, then check it. If you're lean get a bigger jet, and if you're too rich get a smaller one, then do it again and again untill you're happy with it.
Don't forget the air screw and the needle position have a lot to do with it too.
Screwing the air screw in will make it richer, and screwing it out will make it leaner.
Moving the needle up will make it richer, and moving it down will make it leaner.
If I'm wrong, someone correct me.
Just get the bike warmed up then kill it and put a new plug in. Restart it and ride hard for 15 to 20 minutes, then check it. If you're lean get a bigger jet, and if you're too rich get a smaller one, then do it again and again untill you're happy with it.
Don't forget the air screw and the needle position have a lot to do with it too.
Screwing the air screw in will make it richer, and screwing it out will make it leaner.
Moving the needle up will make it richer, and moving it down will make it leaner.
If I'm wrong, someone correct me.
