I had K&N installed for more than 2 years. dint get any appreciable performance wrt top speed and just a tiny increase in pickup, That too after rejetting it with zma main jet. I kind a liked the sound of it. but as i see and heard of reports damaging and killing INDIAN bikes, i'l get it removed ASAP.

One Question,

Do i have to change my MAIN JET to stock ones after removing the K&N or is it possible to get proper air-fuel mixure with the ZMA ones with stock filter??

well, puttin a +1~+2 size main jet with stock air intake will slightly increase performance,but i guess anything above that may make it too 'rich' which would be a waste.. i recommend +1 max for the main jet if on stock box..

well dude i dnt mind u ppl say anything but i am a die hard fan of K&n !
Let me try to make u understand.. K&N is named WORLD's best filter(not Europe's best filter ) and it was originally invented for desert dirt racing where dust will be max(stock paper and sponge filter used to clog)! and i am using r1100 from 15K+ kms in my zma(no jetting), also in my old unicorn i used k&n rc1060 for more than 30k kms! had no issues! Jetting is not compulsory! right tuning is Highly essential and i have got it done! i tour in my Zma upto 180kms to 200kms non stop at 110 to 120 speeds and i never got heating issues too. so moral of story "everything finally depends equally on ur mechanic(tuning) as much as u! "

*Instances by First Hand Experience*
1) some ppl never service their K&N filters and end up loosing performances
2) Some wash their filter with kerosine/shampoo and oil it with gear oil or engine oil again performance is bad
3) A friend of mine argued that recharger kit r all fake and he used to clean his filter with petrol and used a dry filter(no oil) and his engine seized-moral is that oil is most crucial part in trapping dust

Suggestion
1)Dont leave ur crank case pipe hanging open after removing air box again dust can directly enter crank case and ruin engine.(many seem to ignore this)
2)make sure ur engine is not lean after installing filter and proper tuning is most imp part! especially if u ride ur bile hard in lean condition then chances of lessening engine life is more.(check by spark plug colour)

Proof
A good Friend of mine has used K&n right from the 'first day he bought his bike' ie pulsar150 and he has rode 1,37,887 kms till date with only 180's main and has no issues

So conclusion is that K&n with proper servicing is 'Worlds Best' and wit improper service can be worst!

Bro ,Did your oil leak problem solved?

I am also having the problem,Please see here

Debunking the K&N Myth - Why OEM is Better : Nissan Articles

This article is very informative.
Recently, I bought a K&N RC1060 for my FZ. Its a well maintained bike. This is the first modification I have done. Acceleration felt easier, initially.
But now, the engine has become hoarse and its overheating big time while doing high speed.
I guess it does not go well with all bikes, from what I understand from all the posts in xbhp.
I am going back the to the stock. Its better for my FZ. I am not going to clog my bike's heart.

My decision to remove the K&N filter is based on my own experience.

Yes,you are true.I used to have K & N RC1060 in my karizma before,But i removed it due to over heating problem,i hadn't up jetted my carb.Also i dont saw any performance increase except a roar in sound. So personally i don't recommend K & N for bikes after that.

well here is where you went wrong. You Put a free flow air filter but you did not make any arrangements to increase the fuel flow.
Ill explain :
What the k&n filter does is , lets in more air than stock filters. So unless the fuel supply is also increased , you will getting an extremely lean mixture. Hence , the engine becomes harsh , pick up at high revs suffers and the engine overheats.

What you need to do is to "upjet" your carburetor. It effectively means , finding a bigger jet for the carburetor( in laymans terms , a bigger hole so that more fuel flows ).

Thus , the increased air flow along with increased fuel flow will result in better performance.
Many people jump into the world of free flow filters without upjetting. The sound it makes gives an impression that its going faster but its all psychological.
Only a free flow filter + bigger jet can result in better performance.

But still how much power will increase after up jetting and K & N filter?

the sad part is , its not much .. less than 1 bhp gain for indian bikes .. probably 0.5 bhp . But the bike will feel snappier and response will be better..

That's so disappointing!

No power enhancement can equal power gained through increased displacement(increase in CC of engine).

Hehe.But still many people are spending money on this just for a roaring sound and 0.5HP.

Hi,
I know very well what upjetting is. I did a lot of research before buying K&N.
It was a waste of money. Anyways, your info may be useful for someone else. But I still prefer the stock filter.

from your dp image,i guess you have a pulsar... so from 1lt,if 900ml is gone,then i cant be sure what the real prob is... how many kms did you drive for the oil to go to 100ml? what is the odo reading ? what oil were you using ? grade ?
See how the oil consumption is this time.if it drops to less than 700ml in 500kms~1000kms,you have to definately open the head,get the piston rings changed,and the piston if the ridges look worn out.Get the head cleaned and the valves remapped. this should be the first step,after this,you'll have to ride below 60kmph for atleast 1000kms,after which change the oil.Then start checking oil consumtion.It is fine for the oil to go down by 200~300ml every 2k kms. If it still exists,A new Bore Is inevitable. Whnen you open the head and remove the piston now,check if the cylinder walls,if they have any scratches deeper than 2mm,take the opinion of the mech about a new bore,if not,follow what i said earlier.