I am using the Pulsar K&N BA-2201 filter (Highly recommended for all Pulsar owners) and the Bajaj mech himself removed this from my bike, gives a bit roar sound which you normally expect after installing a K&N (which is absent with this filter).

Also, the mech told me to keep this safe, this is not a regular part which will be available in spare part section. So, all those doing this keep it safe if later you want to revert back !!

can u get more pic of how to get to that sensor????which part to unscrew to remove sensor....

Why do you think the manufacturer designed and installed this 'snorkel'? It is there to prevent water from entering the air filter box during washing and rains. Now you may say the seat prevents it. But unfortunately no. Even with the seat on, if you lift the seat after washing or riding through rains, you will see water in the under seat compartment. If the vehicle is washed with pressurised water, then water entry is definite. With the snorkel gone, this water enters the filter box. The reason it is removable in the Pulsar, is to allow fitting and removal of the AF box, since the snorkel comes in between the frame.

What happens next? Pulsars use an oil wetted foam type air filter element with a typical life span of 10k km with a cleaning interval of 3k to 5k km (ie 2-4 cleaning cycles in its lifetime). I believe most Indian bikes use a similar filter. When water enters the filter box, it will wet the filter element. This will erode the oil in it. It is the oil that does the job of trapping dust in the induction air. The foam is merely a stucture to hold this oil. Once the water washes out the oil, 1) it reduces the filtering ability of the element allowing in more dust to the engine, and 2) it releases the dust the washed out oil had trapped earlier.

(R-15 uses a dry paper filter. Water can directly damage this since it's paper, but R-15 doesn't have a removable snorkel, it's part of the AF box AFAIK.)

So, Yes, less filtering, more dust, engine damage.

Acceleration: The increase in airflow is very, very marginal. Not enough to upset AFR, or improve acceleration.The snorkel's opening is larger than the opening on the AF box, so it never restricts airflow. Only the accoustics of the AF box changes when this is removed.

The wheel popping abhiiceman mentioned may be because: listening to the new sound of the engine revving, your clutch release point changed, involuntarily. Most people use the vibes and engine sound to shift. If you are sure you have better acceleration, then i won't argue.

FI engines: Yes, it's bad for them too. True, there is no carburator to get dusty, but the next part is same with or without a carb. Dusty air mixed with fuel burns in the engine. A part of this dust which can combust, burns and leaves soot in the cylinder. What doesn't burn scratches up the cylinder walls, reducing the sealing efficiency of the piston rings, leading to oil entering and burning, emitting blue-white smoke as experienced by on2wheels. Dust also lines the ducts right from the induction to exhaust, blocking sensors, injectors etc...

So, in conclusion, sound changes, but don't be surprised when you get enigne damage after 8-10k km of riding.

yes you need to stuff some cloth inside the filterbox while washing ,actually even i did the same,but while riding in rain water wont splash their ,their may be only slight splashing near the tool kit region because of the gap in the mudguard near the tail lamp..sorry for not mentioning the cloth stuffing thing...
and you really think small drop of water or a stream of water washes engine oil or any oil away?if yes then why do they wash filter with kerosene or petrol instead of water which we get for free..
however i am using this method for the noise which we get while rpm above 4 nothing else,for me this is better then filter because in Aftermarket filter you wont get the stock note while sane riding
yes their will be only a slight increase in air supply hence mentioned tweaking and not complete new setting....

so by this method if engine goes kaput by 8k then for aftermarket paper filters it's 5k max?

No, a small drop of water does not instantly clean the entire air filter of all the oil. But many of these small small drops of water, over a period of 1-2 months (depending on rains / wash frequency) will significantly erode the oil in the foam element.

Next time you wash / park after riding through rain, wait an hour or so. Then go look under the bike where the water has dripped. Under the drain hose of the air filter box, you'll see oil stain, or oil floating on the water. Each time this happens oil is reduced ie. reduced filtering efficiency. I'm not saying suddenly one wash and your filter looses all its oil and lets all dust in. (In Pulsars, rain water (small drops) goes in through the side bottom edges of the seat, where the seat cowl assy. (rear fairing) does not have raised edges, ie mid and the part above the tail lamp. Pic attached, owner: abhiiceman . This goes down to the filter box, since it is the lowest part, and without the snorkel, into it.)


Again, 8 -10 k km is a very rough approximation. It all depends on how much oil is gone and how dusty the riding conditions are. Also, suddenly at 8k km the engine isn't goin to sieze. You'll slowly start seeing increasing engine oil consumption, smoke while starting which will progress to smoke while riding, oil dirtiying quicker than usual, and getting more serious as the kms progress. Why, we already have some one's first hand experience on this very thread.

OT: And about aftermarket filters, if you just search online for independant reviews and comparisons, you'll see than they are not that good in the filtering department either. Eg: Air Filtration Test , K&N air filter or OEM, why OEM is better Even K&N claims only 99% filtering efficiency of stock filter.

Finaly, a person's value for sound vs engine life, or looks vs performance, is entirely his personal opinion. I'm posting what little i know, and have experienced, to let you and other people following this thread, know what they're getting into, when doing this mod.

IMHO i dont think water will enter filter box when bike is left in rain because even if water enters from the seat cowl it wont enter the filter box through snorkel hole because theirs a jap between front mudguard part and filter box,only concern is if you leave the bike for pressurised water wash you must stuff cloth inside the box
and i am confident that this method wont result in increased in dust flow to engine is only because of the presence of stock foam..
anyway if admins feel this may result in damaging of others bike then they can remove the thread....also if it would then they wouldnt hav approved this in the first place...

Thanks abhiiceman for this amazing post. Will to do it on my DST

Hi all,

The somewhat aimilar idea went through my head to get this roar of the k and n on my yamaha fzs with the stock. and I removed the top glove box covering the
air filter. Two days later white smoke started coming out of the exhaust. Things got more worse when the carb started giving some problem and decrease in
the initial pickup was felt. hence I replaced the cover.
my 2 cent: let the stock be stock unless it is known if the changes will not affect the engine or its component.
ps: my bike has a paper element so there might be completely different behavior in your set-up or changes in the bike.