Query Moved and Approved.

its running lean if you are on the oem jet.

you need bigger jets mate!

Yes thats it, you need bigger jets

when you instal a K&N the air/fuel mixture leans out i.e. more air less fuel. This is because K&N is a high flow air filter which simply increases the air intake capacity. So now you have more air flowing to your engine. This disturbs the air/fuel ratio. This balace of air and fuel should be just right and is very tricky.

I would advise you to get a good mechanic to do it for you(one who knows what a K&N is.. The one I went to asked me- "ye kya lagaya hai".."air filter kaha gaya?" )

Now what you have to do is get bigger size main jets and pilot jets for your carb. Usually a jets that are 3-4 sizes bigger do the trick.

If you want to know more there is a lot of usefull info in other threads..
You can also visit

How to: Fit a K&N Filter and Rejet a Carburetor

ride safe

Thanx buddies but can any one tell me which sizw of Jet should I install??

not jets needed get spark plugs clean and also have a look at engine oil...