...
a little happy today... I disconnected the reed switch (rev limiter) and i felt a good throttle response and slightly less vibes, it went till 9k and 113kmph was the top speed i got, though it took some time, the same time it had taken earlier as stock. [there's a small correction, i had mentioned 9.5k earlier as the max rpm, sorry it is actually 9k]. Now feel like my old pulsar stock is coming back.
at 3k rpm when the reed switch is removed there is a decrease in rpm of about 1k.
But still the top speed problem is not sorted...

@psr: i take your advice, but before going back to stock i want to give it one more try, to know whats the maximum a K&N upgrade can give me...
& are crank breathers and the breather hose similar ones (the one near the electrical point from the alternator).


Please guide me. Since even at stock it gave me the same top speed problem. now since the tuning is almost nearer to the right mixture what might be the other problem.. CDI?? has reed switch got anything to do with it?

how much will a new filter and filter box cost?

@pavan- I am saying so about pilot jet not in regards to the top speed, but the torque and low and mid range power

I posted the sprocket info and no comments on it? Wasted effort I guess. And PSR yes it may not be worth it but it sure is a great experiment. And after going back to the stock filter I noticed that the engine RPM climbs a bit slowly on stock than K&N. K&N gives you awesome throttle response. But the noise was too much for me. So got rid of it.

@ARNadal: I am telling you again that there's no need to change the pilot jet. The size of the pilot jet is sufficient stock. Only the main jet needs to be enlarged. The a/f screw needs to be adjusted which you already did.
The a/f screw setting has got nothing to do with top speed as when trying to achieve top speed we open the throttle wide open. At WOT, the pilot circuit is inactive.

I don't say a 38 jet, I mean the next bigger size available, since I don't know what size the pilot jet is on the pulsars. For one time, forget your theory of "PJs have a very small role after 1/2 throttle". There is a large difference in the torque experienced after replacing the pilot jet. Going back to stock air filter will be a waste of all the efforts you have put in till now regarding K&N and getting more power out of it. Take my advice as one more step before turning back.
I can only suggest, pull out your pilot jet, read the number etched on its side. Then find pilot jet sizes for 200 and 220. I'm sure they are bigger. Else you will have to go to a few shops before you can find one, but trust me, it'll be worth the effort.

K&N is a one way street to slow destruction of your engine.Take it off and go stock if you want to have more life of your engine.Ignore this at your expense.

@shubhanker: if i go for 38 pilot jet(pj) , will i have a notable boost in the power/performance. Since pj's have a very small role after 1/2 throttle. Now am thinking of getting stock airfilters fitted. but will defnitely stick On, if i can in any way bring a more notable boost.
Am totally getting irritated with the sound K&N makes. I have just throttling sound and the bike pulls nowhere with the sound? Can pj be the issue

Am not able to figure out where i found 4k tuning, but definitely we have a post in our community where it says 3500rpm. The engine rpm difference is to just help exact tuning, since at higher rpm's fluctuations are easily noticeable and tuning will take less time and will be more precise. I think so

i dont have it here........???!!!
can you please post a pic. what will occur if it is absent...

@pavanchirmade: Ok, but if you are not in a hurry, it might take an indefinite time... am still a jobseeker so finances are an issue.
can you please sent me the those two pics to [email protected] am not able to download it.

the 2180UG4 has 39/14. I know a guy dealing with bajaj spares in my city. Got pics of his sprocket chain chart. He too was saying "Kitna confusion kar rakha hai in logo ne"
If you find an aftermarket front sprocket of 13teeth or a 40 teeth rear sprocket for a 580chain and which will fit a pulsar then please tell me.


I know how that feels. I got rid of my filter. It is sitting on my desk now. I really got fed up of the sound.

any idea about the cause, didnt hear anything after that. and as you no am running with 125mj. now i tried tunning and got it without any sputters (i hope i itz right now).... and it reaches 9.5k better... but the damn top speed has decreased (a high time actually) it is now around 109kmph, and i used to get 113kmph. bajaj n other p180 owners claim 125kmph (with no worries). i had actually wanted a boost, now experience a mere 9kmph increase in speed at till only 5k n 6k. (no where around expectation), and had n still compromising that noise of K&N. now everything is becoming a compromise... (worried and mad)

I have heard that p200 n p180ug4 has the same sprockets 38/14.
I dont know about sprockets from other manufacturer, sprockets are model specific and each model has separate number of fittment holes...
ours has 2 (p180ug3). i was planning to try gearing ratios of (48,50)/(13,14), dont know whether it will be foolish.
Will need to depend on aftermarket ones or from some jugads...
there are two risks we will need to, alter the chain, and those sprockets should be able to bear the heat produced with stress without bending and getting broken (the quality). and if we find some with 2 holes it should match the dimension parametres of the hole with the fitments (i have never seen those fitments, so itz a guess.)
The best way is to search online for parts catalogue of various vehicles, or get in touch with the spare parts in-charges through service managers of authorised stations saying that we are on a project (anyway we are in, ) and have a view of it. but hole dimension will still be unsorted.

If i can arrange finances before you try, i can be of some help, here in chennai there is a place called pudupet... famous for bike mechanics. If we can have an open talk and xbhp backup, they are less likely for mistakes. so "buying each one and trying it" can be saved.
If you have some trusted mechanics have a chat with him, he might have observed sprockets of different vehicles. Castrol bike zone might be the best floor for that.

this cracker used to happen with my bike too....in my case it was like a back kick because of the absence of the exhaust valve decomp mechanism.

Pilot jet is perfect stock. Just open the screw more. All you have to do after changing your air filter is get a bigger main jet. It is not that complicated man.



Any idea if we get rear or front sprockets separately from a different manufacturer? Bajaj never sells them loose. They always sell sets. I would love to have the UG4's rear sprocket.

If the mixture screw is open more than 2 full turns for the constant rpm position, the current pilot jet is lean. Hence go for a bigger pilot jet. If the mixture screw is open less than 1 full turn, the current pilot jet is rich. Go for a smaller pilot jet.
I have never heard of a technique that says tuning the bike at 4000 rpm. The correct way is to warm up the engine and tune it at 1500 rpm.
I don't know if the jets will fit your bike. Since Unicorn and Pulsar use different carbs. However, when in doubt, go for it. I recommend a 38 size pilot jet.
The pipe going down towards Earth is for draining the carb in case of impurities or water seepage. The crankcase breather is connected to the air box. It would be a thick black pipe besides the cylinder.
I don't know why there was a cracker..

@all:

Today morning i heard i loud cracker coming from the engine while i tried to revv (not a heavy rev) in neutral a minute after starting the bike, i think it was from the juncture where the exhaust pipe is with the engine.
I had tuned it to 4n1/2turns from not so tight and went a ride about 55km yesterday night, didnt observe any problem during that ride.
What was that sound.

about the gearing ratio right it seems that bajaj themselves have no clue about it, in the manual its printed as 2.80 which should mean it should run on 15/42 sprocets, mine came out of the showroom with 15/43 which gives a ratio of 2.87 .the replacement kit that i added later was 15/44 which means its currently running a ratio of 2.93 which is way too short for the p180 thinking of adding a p180 ug4 (2.78) or p200 (2.71) sproket kit

as for the mixture screw i dont know man for me it leans out every time i unscrew it as for the workshop manual all i can say is that it has its differences from the actual bikes you and me ride

anticlockwise is richer. you are right about that.even i am trying to find the right ratio.that too on a tight budget.

@kbr100: i found anticlockwise as richer mixture...
@psr: thank you for the picture
@shubhanker: will that both fit mine?
and that is how tuning should be done with a K&N right.. setting it to 4000rpm leaning till the maximum and tuning richer till the engine rpm is constant,.. now itz 4 n1/2 turns from not so tight... now it reaches 110kmph at 9k without much strain, with still some bursts. And i find more booming than engine moving..
And ya itz true that am expecting more and getting frustrated. Will need to check the clutch plates...
@pavanchirmade: i read somewhere that this is how tuning with K&N should be done?!...
And i didnt know that this small difference in gearing contributes a small boost in top end only with a high compromise on time, Shit! difference since the stock is 44/15 = 2.9333 and yours is 36/14 = 2.5714
please suggest me the best front and rear sprocket sizes that you would suggest keeping in mind that i have similar plans as you did, 220F cam shaft. and sometimes getting along with the 200's block piston too. I really feel screwed up in a cycle.

@all: carburetor has in total 4 external connections right (excluding air intake and mixture towards the head) - the accelerator cable, the petrol line, the reed switch and one small diametre hose at the lower bottom leading a path down to earth (what is this?, is it an exit for impurities or unmixed fuel?) and is there any other connection towards the engine from here for engine breathing (something called a crank breather?), or is that an extra fiitting..