a good news and a bad news

hello there.

my run-in of 850 kms is complete.
i was feeling very tempted to push it and i did.

believe it or not, bike has become insanely powerful.
it wheelspins if accelerated hard.
it drifts along the turns is revved hard on exiting corners.

the good part is that there's so much increase in power that the drifts are much smoother and long.
so it makes them safer.

with a pillon, bike wheelies on accelerating.

until 4k rpm, its normal bike and vibes pretty much.
from 4k to 6k it hardly takes a second for the bike to zoom from 60 to 90.
I've topped 120 on the speedo so far, and it is still very stress free, it feels like the bike can do more, lot more.
on higher revvs bike does not vibrate.

however, another good feature is overtaking.
at any constant speed just wack the throttle and bike turns into a dynamite.
it takes very very less time to reach 3 digit speeds.

1 more thing is that the bike's exhaust fires gunshot if revvs are decreased from very high.

all this goodwill lasted only for 55 kms

today, i went to visit a friends place, was 22 kms from here, i reached there quickly, took him along and was coming back.

there was a section where its a massive climb so i was on 2nd gear and pulled it up all the way up, its very small part though, within 5-8 seconds i reached the top, but while reaching bike knocked, which is normal i guess, but these knocks weren't strong enough anyways.

now as i rode it on the free road, it felt pretty much harsh.
but i thought that its a part of the upgrade, the cons with the pros.
and i reached to 80 within no time.
suddenly i heard ticking noise from the engine, wasn't loud either, but on de-accelerating i almost left the throttle but the bike kept on revving harder and harder.

i pressed the clutch and the revs increased to 12k, i didn't even touch the throttle though.
i left it back and suddenly those ticking noise turned harder and harder, too hard and i tried to stop the bike at a corner.

when bike came to standstill, it automatically revved way too hard as the clutch was pressed, so i hit the engine kill switch, it didn't stop however revvs did decrease, and all i could hear was hugh tock tock sound as a big hammer it hitting a big piece of metal.

i pulled the key off, engine still didn't stop.
it kept on making that tock tock noise, it was 1 tock in every 2 seconds or something.

i had no idea as how to put the engine off, i even had the key in my hand,
i hit first gear and left the clutch pressing the front brake, and engine stopped.
strangely the bike took a reverse gear, i.e in first gear it moved almost half a wheel BEHIND before turning off.

i bent down to see any possible problems.
it was all okay from the outside.
i was feeling as something massively has been damaged.
i waited for a while and started the bike, it did start and made that extremely rough noise just as before.

i used the same method to turn it off.

i had to pull the bike all the way to my friends building (5 kms roughly), and its standing there.

i am broke, physically as well as mentally, and have nothing left in my pockets to fix a crank damage.

what should i do ?

Can you tell approximately as to where the knocking noise is coming from? .Did it come from the bottom half or the engine?
It is obviously mechanical,but the bike wasn't switching off? and kept on over-revving even when the ignition was turned off? That sounds like a electrical problem combined with carb(stuck-butterfly).
Yes could be the main-bearing problem or the connecting rod and worst case scenario would be crank shaft problem.

The other relatively cheaper(compared to carank-shaft) issue could be the valve hitting the piston .Which could be due to the failure of the return spring.
Crank-shaft can be re-set at lathe and that involves main bearing and the whole crank shaft assembly.If the crank is damaged ,then it can be re-set at lathe.

I am sorry to hear this Gagandeep,let's hope that the damage is minimal.

sound of knocking is from the engine, i don't know weather bottom or top.

how come valves hit if the piston had been made grooves?

besides, when i turned off the ign key, the over revving stopped and that hammer hitting sound started.

1 more thing
as i mentioned in the earlier post, i did kick start it, and it did start.
bottomline is that if my kick went all the way down, how can the crank be damaged??

If the knocking noise was less compared with the rpm then my guess is its got to do with the engine-head.
could be a cam-shaft bearing,or the valve guides,spring or the rocker arms.

As it is a mech has to take a look at it.Let's just hope that it has to do with the engine-head.
If a return spring fails then the valve will hit the piston and it will get bent.

Since on pressing the clutch the bike over-revved.I am hoping that the crank is ok. The reason is once the clutch is pressed it frees the load on the engine .The thing which is bugging me is ,why did the engine reach 12k rpm when the clutch was pressed that too when the throttle was at zero position?

You just experienced pre-ignition. It happens because temperatures in the cylinder go high enough that the air-fuel mixture is ignited without the need of a spark, the phenomenon is often refered to as 'dieseling'. In carburated engines the engine can continue to run even after the ignition is switched off. preignition happens due to hot spots in the cylinder that have reached extreme temperatures or even carbon deposits that glow red hot and cause preignition. The carbon deposits reason is quite common on 2 strokes but i havent seen it happen on a 4 stroke (unless you're leaking oil into the combustion chamber). Otherwise on a 4 stroke its most likely caused by sharp edges in the cylinder or piston crown (like poorly cut valve recesses) that get superheated. Either way when this happens ignition is out of control and often runs super advanced which causes the engine to run in reverse. Thats why your wheel jerked in reverse when you engaged gear. You're going to have to examine your engine, ignition timing and jetting thoroughly to determine what caused pre-ignition to occur.

Coming from you i think that might just be it.Yes his bike has a new bore kit with newly cut valve recesses and i don't know whether head was checked .I certainly hope that the combustion area of the head was enlarged other wise as you know piston might have come in contact with it when it expands due to heat.

Anand

firstly its an honor to hear from you killer.

even i had the same thing in my mind.
since the bike was heated, it started, if it would have been cold, it wouldn't have been.

1 thing can also be there.
since my head was old one, and the blocl was bigger, and the ONLY reason my head wasn't bored was because the piston fell exactly on TDC.

there could be a possibility that piston hit the head as gixxer mentioned.
valves recesses were cut, but maybe they weren't upto the mark.

my bike is 22 kms away, and i will get it home tomorrow, i'll have to drag it all the way home, will take all day.

I'll realize things when i open it up, but for now.
if in case my piston did touch the head.
and all that caused this problem,
what damage is done totally.

is it a major one or a minor one (not soo major one) ??

i can settle down with a new head of A180 itself.
and i can do small knick knacks below.

so tell me honestly is it worth spending to make it right ??

@Nanotech

Don't be hasty buddy,if its just as killer put it then its a matter of tuning the carb and checking the rest.
I am using the old head for a bore of 65.5 mm ,so there's no need to change the head.Get whatever that's wrong sorted out with this head itself.
Coming to the idea about the head combustion area expansion being an issue, lathe guys usually take care of the bore size and the squish area expansion to accommodate it.So that is a very remote possibility and considering the fact that the new bore was ok for over 800 kms.That pretty much rules it out.My guess is ,it's a valve train issue if a mechanical failure did happen.

Let the mech check the bike and let us know about it.Simply don't go around buying a new head.
Whatever damage has happened ,if at all any mechanical failure happened that is .It can be sorted out ,don't worry and it will be cheaper than buying a new head.

Anand

As killer explained the pre-ignition part,i think valve train failed once the revs hit 12k rpm.The rev-limiter is obviously of no use when pre-ignition happens .So it couldn't keep the revs within 9.5k and on top of it no head work was done where they check and re-set the valve train.So hopefully it won't have anything to do with con-rod or the crank bearings.

Anand

Friends i think we should be thankful to killer for explaining to us ,as to what happened with nanotech's bike and how the bike behaves when pre-ignition happens.

Killer you are Absolutely spot on.If the valves are bent or not seating properly then the vehicle will actually stop,and not run.The reverse running indicates pre-ignition..ie., ignition taking place in advance .It is so advanced that the piston starts to run in the reverse direction.Either your CDI or the pickup coil is kaput or most probably HEAT..since you were able to ride it .Did the vehicle start normally after it cooled down ? and it goes forward or backwards then?..if it still has the problem after cooling down then CDI and pickup coil have to be checked. Do the checking one at a time,and leave it to knowledgeable mechanic ,if you are in doubt.

What's causing the knocking sound?Something mechanical right?

thank you all guys for showing support.

today i went back to my friends place to bring back my bike.
the first thing i did was sit on the bike and very very slowly i tried to see the kick's travel holding the clutch.

the kick went gently all the way down as it does in stock.

i switched on the ign key, hit neutral and tried to kick start the bike.
believe it or not, the bike did start in 1 single kick.
and was humming like a bee

it was idling very very smoothly at constant 1.7k rpm.
i revved a bit, pulled it to 2k initially and it was revving nicely.

i tried to revv till 4k once or twice and very smoothly it was vrooom vrooom till 4k.

i was shocked and surprised.

sitting on the bike with main stand on, i pushed myself forward and hit the 1st cog, i was seeing the rear wheel and it was rotating very very normally.

all was just as it was, smooth and silky, no one can say that this engine made that hammer sound.
i got it off the stand and tried to ride till a small distance, it rode normally.

i was still scratching my head as how this could happen.
bike was behaving very very normally.
i switched it off, and tried to start again, after 1 or 2 massive kick backs it did start.
again it was behaving very normal.

i hit the road, and bike was performing amazingly, same upgraded power and all was smooth and silky.
i even stopped at a corner and was carefully listening to my bike's engine for any sort of unusual noise.
all was very very normal.

i rode towards home, i did try to rip it, as i wanted to make sure that is the problem gone or not.

i did a very quick 50-90.
i did it again 2-3 times, suddenly the same thing happened.
after a kilometer or so of riding, once when i revved it, REVVS DIDN'T COME DOWN.
it was precisely 7.5k
i pulled over, hit the clutch, saw the revvs reaching 7.5k and that tock tock tock tock noise from the engine started.
i did bend down and listened as where it was coming from, it was the head, i am pretty much sure.

as soon as i turned off the engine using kill switch IT DID TURN OFF and those noise also stopped.

notice this pals, whenever the revvs increased, the tock tock noise was slower compared to piston's travel speed i believe.
it was like 1-2 tocks in 2 seconds, even at 7.5k rpm.

i was waiting for a while and kicked it back, it started, but that 7.5k of revvs still continued.
after revving for a few seconds, the noise starts.

now since my bike is starting and behaving very very normal initially, i feel there's nothing MAJORLY damaged.
besides all my electricals are okay, as revv limiter is working, everything else is also working, suddenly why those revvs increase ??
i noticed the butterfly valve too, carb is hardly a week old as all of you already know, there's nothing wrong with it.

whenever the bike heats up, this things happens.

what i think can be a problem is the HEAD.
maybe the piston is getting hot and expanding.
it may be traveling say 0.1mm more towards the head.

AS THE HEAD IS NOT BORED AT ALL TO KEEP HIGH COMPRESSION, THERE CAN BE A POSSIBILITY THAT THE PISTON MIGHT BE HITTING IT.

after this, i and a buddy of mine, towed the bike all the way home, that classic 2 guys on 2 diff bikes and the one behind pushing with his leg the guy in the front.

we took turns to cover 22kms, was a good experience though.
bike is standing under my house now, what should i do ??

@Nanotech

Good to hear that your bike's ok buddy .So thankfully there's nothing wrong with the crank and the reciprocating parts.

Get this clear

Do exactly what Killer and psr have suggested .Your bike is running seriously lean and looks like the timing has to be checked again.

Get the bike's head opened up and pleasedo get the head matched with the bore.

STOP PLAYING AROUND WITH THE CARB

If the bike continues in this same state it will seize.Take my word for it!!!!

You are lucky that nothing has happed during the running in period.I've told you buddy ,stop fooling around with the carb and get the carb tuned ASAP
If you continue riding in this state you will ruin the new bore-kit.

@Nanotech

Killer and psr have got it spot on.Do as killer has suggested and gladly nothing serious has happened yet.