Remove the air filter and wash it with kerosene or diesel.
Without oiling it fit it back.

Kick start the engine,it should be at its operating temperature.
Now start the bike and turn the Air screw fully clockwise.
Start unscrewing the idle screw until the engine stalls.
Then turn the Air screw one turn out(anti-clockwise) and increase the idle rpm by screwing in the idle screw(clockwise.)

Listen to idle RPM and start tuning the carburetor.

If the screw is still not responding check by pulling choke lever if the engine dies or RPM decreases too much then you are running rich.If RPM increase and comes back to idle slowly then it indicates that your mixture is too lean
Check for any leaks.

A perfect tune should give good throttle response.

Air filter cleaned 500 km before, carburettor has also cleaned recently and o-rings too have changed. I think that is happening because of valves. As sibun ji said the mixture will not swirl now.

How is the bike running now ?

@paul- from your description your airscrew is not responding. the problem is not in carburettor or valve. the problem is with valve timing. you are saying pick-up is good. so you have advanced the timing by 2 or 3 teeths. so set the timing correctly and retune. your tuning will be correct and also change the spark plug because due to in correct timing your plug would have been sort. presently typing from phone. tommorow morning i will provide the details.

I'm 100% sure that timing is correct, i've match both of the points i.e, T Mark and point on a socket with that mark on a head....and my spark plug is also new.

@pinaki ji
bike is running good, pickup increased only valves are noisy and carburettor air screw is not responding.

Ok so grit is related to sand paper , i thought it is something different .
Is you get some big size ( A4 or big ) sand papers of the respected grit's in 100 rupees or some small & some big as in pic ?

Ok will check there .

Ok .

No one with battery mod ?

OK,As sibun said he is typing it from phone let me post the procedure to check timing.

Remove the Timing chain sprocket cover
Remove magneto cover
Make sure the engine is at TDC of COMPRESSION STROKE.
How to check compression stroke ?
Well,there are two methods to do check it.
1)Remove both the tappet cover and both the tappets should have some play when the magnet T is aligned with index mark on case.If not then rotate the magnet one full turn anticlockwise.
2.When the magnet is rotated slightly in either of the direction,less force will be required to rotate it(you will feel some play).

Now the circle mark on timing chain should be inline with the index mark on cylinder head (It should perfectly horizontal).

After taking care of parallax error,make sure the sprocket is aligned correctly.

If you advanced few teeth then-
Remove the chain tensioner spring by removing a #14 bolt which is just beside the oil drain bolt.
Use a small screw driver and lift one end of the chain from the sprocket and just take it along the perimeter of the sprocket to make necessary changes.

Also make sure the chain tensioner is working/installed correctly.

EDIT:
@above_all
You can fix the battery by using some t\kind of metal ties.

Silicon carbide paper is available for Rs.10 per sheet here in Hyderabad.

Only 600 got about A4 size rest are all half of it
one 2000g paper which is half of A4 cost 35 now which was of Rs.7 for A4 few years ago.

I've done as u said, its perfectly horizontal i mean both when T mark is perfectly vertical then circle mark is getting perfectly horizontal.

You have said the correct procedure but one method is wrong.
The wrong in the above method is that never adjust the timing with tensioner removed. Always timing must be adjusted by tensioner in place, because if you adjust timing with tensioner open then when tensioner is in place sometimes timing gets off mark.
Sometimes the timing mark on the sprocket is mis-aligned from company and creates problem.In this case the timing is adjusted by looking at the hole for the bolts on the sprocket. Both the holes must be perfectly in-line with the mark on head.
@paul- The t-mark matches two times with the marking.
1. During compression stroke and
2. During exhaust stroke.
If you have matched the timing with the TDC at exhaust stroke then also problem will be created.
Ok, do these steps and report:-
1. Just take out the timing sprocket. Use a thin screw driver to dis-mount the sprocket from cam and using a nose plier hold the two holes of timing sprocket and take it out.
2. Using the nose plier insert the ends into the two holes of cam and rotate the cam so that both valves are closed and the cam becomes free i.e it will rotate freely to some extent in both direction.If the cam is free then both valves are closed.
3. Do not remove the tensioner. The tensioner should be tight. Now match the t- mark. No matter it is in compression stroke as you have manually closed both the valves.
4. Now lift the timing chain using a thin screw driver and insert the sprocket by holding it with the nose plier. now keep on rotating the timing sprocket by one teeth at a time by lifting the timing chain using screw driver and rotating the sprocket using nose plier. Pay special attention to magnet as it will move. If it moves slightly then also timing will be bad. better find someone to hold the magnet.
5. When you see that the timing matches i.e the holes, the mark all are in-line with the mark on head. Sometimes the mark is defective. In that case see that the three holes on timing sprocket are perfectly in-line. Now with the screw driver push the timing sprocket and mount the sprocket on camshaft. Now slightly rotate the magnet and match the timing and see that timing match. If not then re-try the above procedure.
6. Now rotate the magnet and match the holes with cam shaft hole and fit the holes. Once again check the timing.

Timing should be matched on TDC at compression stroke and not on TDC of exhaust stroke. Also do it with tensioner in place.
If the timing is advance then your air screw will not work when tightened and if timing is retard then then your air screw will not work no matter how much it is opened.
Do it once again and report back. If it doesn't work then there is problem in air screw.Usually when the o-ring in air screw is damaged or is placed in wrong manner then also air screw will not work.
While fitting the air screw always put the spring on screw first,then the washer and then the o-ring. Now hold the air screw with the o-ring facing up or the tip facing up. From the tip end the o-ring will be first, washer next and spring last or from the screw end spring fast, spring next and then the o-ring.
While inserting in carburettor never insert the screw in carburettor. This way the o-ring will fall in a wrong way into the air screw hole and will give in correct setting. Hold the screw facing up(obviously up otherwise all will fall) and insert the carburettor on the screw not the other way. Once the screw is fully tightened then you can put the carburettor straight.
The most common problem in fitting air screw is when you fit the screw by inserting it into carburettor and not by inserting the carburettor on the screw.

@Sibun
As follow the exactly the same procedure when i fit the sprocket for the first time and rechecked two three times....again today i open to confirm. Actually when i match the circle with mark on the head the two bolts doesn't stay parallel to the ground, our head is not 180* so the bolts stay horizontal with respect to the head.
I opened it again, followed the same procedure, and this time i rotate it anti clock just one teeth to check what happens, and the pick-up decreased and the bike is pushing very hard to go beyond 60. I realized this is not good timing, previous timing is the correct, and i returned to that.

I know this is the correct timing, u can believe me i'm not dumb in such things.
When i tried to adjust the screw both times, air screw not responding at all. But when air screw is fully closed (on previous setting) i turned the choke and bike shuts down.

Also the o-ring of here was also found damaged

so i went to the ASC for new one, but unfortunately the one i got have right diameter but its tinner and the fuel was leaking so i was having one old local o-ring and using for just temporary purpose for now, if u've part number then pls give me... and i think, not sure, the bike may be sucking air from that. when i sprayed the carb cleaner the rpm doesn't increased.

Edit: Regarding carburetor air screw oil-seal.....its seat perfectly on its place...im sure.

One more thing...i was going to open my head today but unfortunately is stopped because when i previously removed the head the exhaust pipe hit the one long rod (the 4 long bolts where block and head stays) and the block feel the jerk and the Mobil leaked from bore packing.....it was my carelessness.
I think now the mobile is started leaking.....not sure...so i cleaned it perfectly to check further leaking....i'm worried
if it is leaking then? opening a block and refitting it may damage the bore i think...whts your recommendation?

Ok i will get the part number today night itself.
Also change the air screw of carb to new one.
The new air screw will consist of air screw, o-ring,washer and spring.
You know how to fit the air screw. Today night i will get the part number.

You know i cant wait to change my valves...its noisy....will that noise will go after new one?
and u know the price of o-ring of carburettor bowl (where fuel collects & there are two jets)? my ASC mechanic told me its priced for Rs.500

I got the float bowl o-ring for Rs.13/-.

@Sibun
Thanks for the info,I will correct my post.

lol i get that too, is there any other o-ring inside carburetor? no?
Is jets are available??

My passion when ridden at high rpm ( around full throttle ) in lower gear make sound's like crackers , my mechanic checked & said Valve Assy. Air Suction DIAPHRAGM needs replacement , but its not come seperately , it comes as complete valve assy & cost around र 800 rupees . Any one knows any aftermarket one available or any other fix ?

@paul.1911 HeroHonda Passion's Cylinder Head Cover Inlet Pipe O Ring's technical name is "O-RING, 27X2" and part number is "91301028000" it will cost you around र 6/-
There is only 1 type of O Ring in Carburettor assembly of Passion whose technical name is "GASKET, SET" and part number is "16010198901" and it costs bomb around र 710/- for only 1 piece . I hope the price is wrong or it may be complete SET of each & every Gasket/packing
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