How will I know if I'm running Lean?

I bought my bike used several months ago and found that it has had some modifications done to it. Aside from the suspension being lowered an inch and a half, there was a Jardin RTone can on there, but running a stock filter. The filter accounted for the bike not being able to rev over 7k without losing tons of power and was replaced with a K&N.

The question now is...how do I know if the bike has been jetted or not?

If I'm running lean, how will I know this?

If I just have a filter and slip on can will shimming the needle be a suitable alternative to an expensive jet kit?

[johnnyrod]

First, you don't without taknig the carbs off and opening them up. Surging on part throttle, or it feeling like it's speeding up as you strat to close the throttle are symptoms of leanness, but to get it sorted you need dyno set-up. Needle shimming can only fix the midrange, the top end will still be lean, you need to upjet, but there's not simple answer without a dyno. You don't necessarily need a DJ kit, it's just a set of jets, needlse etc, the dyno operator might be able to do it just with different main jets.

PS there will be people on svrider.com that will prbably suggest massive main jets, I don't know why, that's just the way it is!

Originally Posted by ClemsonSV

If I'm running lean, how will I know this?

?

A keen nose