Prince...

is this your upgrade...?
p150 with p180 piston & piston rod, stock (bore, cylinder, head) and stock stroke length, but increased stroke speed...

Knocking

I found this on Yahoo answers


"To a lot of technicians there is a major difference between a knock, a ping, and a rattle inside an engine.
1)- knock- when an engine has excessive wear between bearings(rod or main) and parts actually make contact.
2)- ping- ignition spark pre or post detonation. This can be caused by several factors. a) bad fuel, b)timing, either static or advance. 3) faulty part. Everything can be correct and a faulty knock sensor can give a false reading. This can cause the computer to advance the timing and can cause ignition ping. An external part can actually make a noise that the knock sensor picks up.
3)- rattle--this can be when a lifter has lost prime and there is excessive space.
These are just some examples. To me a knock is bad and indicates serious engine problems. "

This is from Wikipedia

Engine knocking - Wikipedia, the free encyclopedia

"Knocking (also called knock, detonation, spark knock, pinging or pinking) in spark-ignition internal combustion engines occurs when combustion of the air/fuel mixture in the cylinder starts off correctly in response to ignition by the spark plug, but one or more pockets of air/fuel mixture explode outside the envelope of the normal combustion front. The fuel-air charge is meant to be ignited by the spark plug only, and at a precise time in the piston's stroke cycle. The peak of the combustion process no longer occurs at the optimum moment for the four-stroke cycle. The shock wave creates the characteristic metallic "pinging" sound, and cylinder pressure increases dramatically. Effects of engine knocking range from inconsequential to completely destructive."

Improper ignition time (too quick or too slow) can lead to knocking, overloading can lead to this improper combustion... it is piston that contributes to knocking sound...

as far as i know...knocking can also be due to
* overheating, (well in your case OH can be a reason. )
* Is that you who changed to new exhausts? exhausts can also lead to knocking if gases are restricted flow,
*crankshaft bearings can? (another possibility in your case)
* improper delivery of power, if the flywheel is damaged can also lead to this
* load on alternator, stator coil (another possibility) ~ improper winding or low quality.
what your mechanic at A.S.S told about piston noise is knocking...

in my knowledge it is piston noise that is refered as knocking, and issues told above are reasons, which are most oftenly mis-understood as knocking..

In your case some reasons highlighted above might not directly contribute or have a noticeable share in your case..
So start a proper troubleshoot with the jet, itz a long Que of possibilities...
all we can do is guess the possibilities and tell you... we dont have an oppurtunity to have a test ride on your bike..

Please correct me if am wrong, i have found some having opinions claiming it to be wrong...
So prince... try to reason my statements for yourself before taking it in

i really don't understand why you want me to change jet size......i have not done any significant modification. its a bit difficult to think why a stock jet should not perform well. i will discuss this jet matter with my mechanic. see i am already getting a low mileage of only 40kmpl.

Ok..

Keep us updated

hey all pulsar experts.............where are you.................HELP...

@ prince

the plug should be brown in color to be completely perfect mixture, even i agree with PSR, seems that you are running lean, why don't you post the close up snap of your plug ?

regarding the knocking issue that started over an year ago, i think you have damaged your CON-ROD bearings with prolonged knocking.
the heat and knocking doesn't seem to be related directly to each other.

1 more thing, did you open the carb completely and re-attached it, maybe your air or fuel screw has some problem, the heat issue (considering you piston and oil are upto the mark) only highlights the carb problem.

get your con rod bearings checked, i think they have taken toil from last 1 year, and have finally given up, maybe your mech when installed the new piston kit, didn't check the play.

but first and the foremost, do upload your spark plugs pic..

ok....i will post the pics of my spark plugs on sunday.

bearing and all are perfectly ok......as they were properly checked duriing reboring work one month back. actually i am not sure whether it is knocking or piston noise.

regarding the carb, yes it was completely opened two times--once for replacing diaphram and slider block and another recently during engine reboring for replacing float, float pin and a few other things, but over heating problem pre-existed, before all this.

i have a doubt that my stator rewinding might be loading the engine too much and therefore the engine si running hotter, that is why, spark pplugs give an indication as if engine is running lean. confused.

will check carb in detail on sunday.

its definately not because of the coil my friend.
i am running a 35 amp alternator, imagine the load it puts on the crank, but still bike doesn't knock.

is your timing set up properly ?

ok, i will get the timing checked too, can you tell me how timing is checked and set. what is the standard procedure for it.

just one thing 35 A stator???? how come?? i want to know the details?

the timing can be checked by your mech after pening the head cover.
get the tappets clearance also adjusted so that it can rule out that possibility too.

regarding the 35 amp alternator thing, read this http://www.xbhp.com/talkies/desi-bik...tml#post598694

are you sure that sound you hear is really knocking, and nothing else ?

no yaar, i am not sure whether it is knocking or something else, ASS says it is piston noise .....i m confused ....

The number of turns alone is not enough to get the perfect mix. I have a friend whose P180UG3 had to be set to 8 full turns to make the spark plug chocolate brown. Looking at the service manual, I set his carb at 2.5 turns and it ran too lean. The spark plugs clearly showed the same.

Also, to check whether the mix is lean or rich one needs to read the spark plugs at different throttle openings. One at a little opening. Little throttle opening will bring the pilot jet into the picture. The screw that we set controls the flow through the pilot jet.
Another reading has to be taken at WOT [Wide open throttle]. When you open the throttle completely, the main jet comes into the picture. The WOT spark plug reading will tell you if the main jet size is adequate.

Note: WOT test is to be carried out in the following way:
1. Find an empty stretch of road.
2. Start the bike and start riding.
3. Rev through each gear and finally open the throttle wide open and gain some speed.
4. Kill the engine using the kill switch, hold the clutch and freely coast to a halt.
5.The color of the spark plug at this moment will show your main jet readings.

I had a similar problem of knocking when i was using some Castrol power 1 oil recommended by BASc ... but then I switched to Motul 5100 and the problem completely disappeared... now i've poured in castrol 20w50 in P180 ..and this problem shows up again along with it the engine oil is seeping around the gasket,it is not leaking excessively..just seeping around the round rubber ..the engine oil level is above mark
Behavior is typical
1. After idling in the morning the engine produces slight knocking sound when i rise the throttle ...that is when there is load on the engine.
2. after 7 Km ride..the bike runs smooth,no knockings..revs crisply..
3.leave it for a 3 -4 hours ... bike comes back to normal,produces knocking sound but slightly less than morning.

Checked the sparkplugs it is black at the tip,brown on the threads.
Mileage is 40, screw is tuned 3.5 turns from complete_tight_position



if it is rich why does it poroduce a knock as if there is no circulation of oil in the engine? due to engine oil? and what about the leak? due to overheating?

when the engine revving crisply engine heating is normal but when it knocks its temperature rises....
after a 90Km ride and going through city traffic , i could feel the heat on my legs ...

what exactly causes this knocking ? since i am running slightly rich engine is supposed not to produce knocking.



I'll carry out this test, I had checked the LHS sparkplug since i do not have the tool to open the right one. Does it make a difference?

AFAIK LH spark plug is the main plug and the RH is the subordinate one.

do you mean to say that i have done 1500kms since last servicing ....so if i open the plugs they wont give me the correct reading. instead i have to get them cleaned and put back in then go for a short ride and check, again adjust the carb, clean plugs and go for short ride and check plug and so on till i get a good reading. this is a really cubersome process if you mean this.

regarding your friend's P180, did you tried to find out, why it required 8 full turns to get a good colour on spark plugs, what was the reason his bike required such extreme setting. and i am already getting only 40kmpl.