pistone broke... whos fault? [Archive]

Megazoid

9th February 2006, 07:36

i've had my 1986 FZR400 for a few months. it has always been smoking black smoke out of the exhaust . i could never figure iout why it was smoking and 2-3 times when i was taking it to fix various things that i broke, i was asking the guy at "KG Motorcycles" if that smoke is something to be worried about, but he told me that it's just gunk because the gas in new zealand is not very good, and that i should take it to the highway and to rev it out once week or so... so i did, and one week i put a lot of strain on the engine, then stopped for 10 minutes, and when got back on the bike, the bike didnt sound right, and i reved it a little, just before the red line one of the pistons broke in halfs... now my friend told me that my valve has been bad for some time now, and that i should have had it checked...

so that's why i'm posting here... is it guys from KG Motorcycle fault that he didnt checked the valves all tho i've told him about the smoke, and asked him directly if that could harm my bike... do i have any chance of getting any money of him?... cause i've spend sooooooo much money on that bike... just last week i've changed speedo, front tyre, and tuned carbs all together like 400-500... and now the bike itself cost like 1000 tops if i sell it for parts...

SimJen

9th February 2006, 07:47

It sounds like its your fault for wringing out an old bike.
Were you willing to part with big bucks to get KG to strip the motor and check for worn parts?
Machines don't last forever, no matter how much they are looked after.
With an old bike the smoke would likely be caused by worn rings or valve stem seals. If the ring broke it could jam in the bore and cause a piston to break.

Megazoid

9th February 2006, 07:50

yeah... but that's the point... i didnt know what was the problem, and the dude told me that the smoke is totally normal... i could have changed the rings... but now the whole engine is a pile of garbage

imdying

9th February 2006, 08:00

i could never figure iout why it was smoking and 2-3 times when i was taking it to fix various things that i broke, i was asking the guy at "KG Motorcycles" if that smoke is something to be worried about, but he told me that it's just gunk because the gas in new zealand is not very goodWell, that 99% of motors you see about town not doing this should've been an indication that this was untrue. Heh, KG motorcycles eh... back when I was a youngin and a group of us were cruising about on bikes, even then KG motorcycles was one place you didn't wanna take your bike :D

marty

9th February 2006, 08:13

free revving a 400/4 to redline? that obviously had a problem? no wonder it broke.

black smoke - probably running too rich. nothing to do with rings/seals etc. the garage guy sounds right that it was a fuel problem.

how much did you pay him for this written opinion that your bike was ok anyway?

T.W.R

9th February 2006, 08:17

Sounds like both of you are in the bin over this one.:Pokey:
Having a older bike that you know isn't 100% & still wringing it:bash:
KG for sayin what they did (old fallacy of days gone by, mainly 2strokers took heed of that rule):bash:
Black smoke is usually indicative of being over-rich, Blue smoke is oil related and without doing an explority its hard to pinpoint an area where the damage is<_<

Megazoid

9th February 2006, 08:18

what written opinion?... it wasnt a written opinion... but i had my brother with me, and my friend when he said it

it wasnt running rich... the carbs are juuuuust tuned... perfect...

Megazoid

9th February 2006, 08:19

thanks for all your help guys... oh btw, anyone needs fzr 400 parts?... quite cheap

SimJen

9th February 2006, 08:37

If it was the valve a compression test would have confirmed. But a lot of old bikes smoke.
Not really the place to publically blame a company, take the issue with them.
I know what they will say.....

Motu

9th February 2006, 08:58

Screw him for all he's worth - that'll teach him to become a motorcycle mechanic and think he'll get pleasure out of fixing bikes for other people...take him to the cleaners,who cares if it's your fault - that's not the point.

imdying

9th February 2006, 08:58

I have a friend in Chch with a few FZR400 parts, quite possibly an engine, PM me.

Sniper

9th February 2006, 10:24

Mate, your fault unless you asked the guy to take apart the motor to find out whats wrong. He did as you asked, Im sure you would have been annoyed to find out that he took apart your engine to see what the cause of black smoke was when you were only expecting a tyre job

marty

9th February 2006, 11:06

what written opinion?... it wasnt a written opinion... but i had my brother with me, and my friend when he said it
my point exactly

it wasnt running rich... the carbs are juuuuust tuned... perfect...

so if it wasn't running rich, why the black smoke? it's not oil, must be fuel. i'm pretty sure the carbs on my scooter are tuned as well as they can be, and i don't get any black smoke. ever.

slob

9th February 2006, 12:21

... but now the whole engine is a pile of garbage

This could be the perfect opportunity to stick an FZR600 (or even better a YZF600 Thundercat) motor in it! Heaps of people do this as the 400 motor and 600 motor have almost the same dimensions. You'd want a complete wrecked bike though as you need the rad, carbs and airbox off the 600 too.

R1madness

9th February 2006, 13:57

Jackrat

9th February 2006, 18:39

Hey man i have a FZR400SP exup that is sitting around that i would be happy to strip out for ya. Motor runs good. Make me an offer. either for the motor or the whole bike. :rockon:
Ian 021 1876987 or 03 9816399

Hell man don't put your fucking phone number on a public forum.:wacko:
Plus when he roots your motor he's going to be looking to blame somebody,,,guess who??

hXc

9th February 2006, 19:28

Hell man don't put your fucking phone number on a public forum.:wacko:
Plus when he roots your motor he's going to be looking to blame somebody,,,guess who??

Why not put his own phone number on a public forum? He's obviously quite happy to do so and he doesn't need other people telling him what to do. Man, this shit pisses me off. I want to live my life and do what I want to do. Just the same as him.

Leave him be. If he wants to put his phone number on a public forum then it's his choice, not yours.

And Megazoid, sounds like your a dork for believing him. 4 strokes SHOULD NOT SMOKE AT ALL. If a 4 stroke is smoking, you just tuned it etc then it'll probably be major. Unless it wasn't tuned properly. Shouldn't have wrung it's neck though.

/Rant over. Just annoys me to see others telling someone else what to do when there is no real problem

Jackrat

9th February 2006, 19:56

Why not put his own phone number on a public forum? He's obviously quite happy to do so and he doesn't need other people telling him what to do. Man, this shit pisses me off. I want to live my life and do what I want to do. Just the same as him.

Leave him be. If he wants to put his phone number on a public forum then it's his choice, not yours.

And Megazoid, sounds like your a dork for believing him. 4 strokes SHOULD NOT SMOKE AT ALL. If a 4 stroke is smoking, you just tuned it etc then it'll probably be major. Unless it wasn't tuned properly. Shouldn't have wrung it's neck though.

/Rant over. Just annoys me to see others telling someone else what to do when there is no real problem

There HAS been a problem with people from KB abusing other peoples PH numbers.
It's already happened,I don't want to see it happen again.
So,,,there IS a problem,,,seems pretty relivent to me an that's why I posted it.

GB500nz

9th February 2006, 20:10

Everybody's quite right that the so-called mechanic was wrong to say the black smoke was normal. It ain't, and it has nothing whatever to do with the petrol you use. But a rich mixture would have lessened the possibility of piston seizure. You broke it. An aging sportbike is going to break if you redline it. Put another old motor in and do the same and you'll end up with another busted engine.

R1madness

10th February 2006, 07:04

Hi Jackrat. Thanks. I dont mind the odd call. I work as a Telecommunication tech at the moment, so its a bit of fun to trace those numbers back and call them (its instant if you have an exchange lock set up). Its even more fun when you give the police their number and address. Hehehe. Point taken tho. Was only trying to offer help to someone that has had a little bed advise.
HXC. Appreciate you living your life according to your own rules. Good on ya man.

crash harry

10th February 2006, 20:41

This could be the perfect opportunity to stick an FZR600 (or even better a YZF600 Thundercat) motor in it! Heaps of people do this as the 400 motor and 600 motor have almost the same dimensions. You'd want a complete wrecked bike though as you need the rad, carbs and airbox off the 600 too.

You tried finding an FZR600 motor recently? They've all been snapped up and those that haven't are bloody dear for what they are... Most wreckers seem to want about 2 - 2.5k for one! FZR400 engines are a dime a dozen though, wreckers seem to have heaps of them lying around.

inlinefour

11th February 2006, 00:08

I have restored a few of these older bikes in the past (1970s) and allways worked on the theory that if they was not thrashed then they would just keep ticking. Now it sounds like the engine in question had issues, but its hard to say exactly what without having a good look. Because the engine was rung out resulting in failure, then the responsibility for the eventual death should, IMO fall completely on the operater. rather expensive lesson to have to learn, but do treat it as a lesson.:crazy:

quickbuck

11th February 2006, 08:57

Wringing an engine because it seems faulty will fix nothing!

It is like smacking a TV because it won't work.

It might feel better doing it, but you are doing nothing to fix the fault.

Infact ringing any engine to redline without load on it is no good. (Okay, with the exception of gas turbines and others, and I'm sure there are some others).

Megazoid

12th February 2006, 09:39

thanks again all you guys for the words of advise, and this is personally for Jackrat... SCREW YOU!!!!!!!!!

now that's that out of the way...
(for one, i was wrong... i was really tired that morning after a night shift at the restourant... the bike is not 1986, it's 1989... infact 1986 is not when the bike was made... it is when i was made... woopsy...)
the reason why i was asking thous questions is because the dude precisely told me three stinking times that that smoke is ABSOLUTELY normal for a sport bike... it has to do with shitty new zealand gas, and that there's nothin that could or should be done. it is NOT because i'm a jerkhead and i want wege money out of anyone, it is simpely cause it is my first bike, and cause i knew NOTHING about taking care of it... but if there is still a person here that thinks that i am wrong, and i should not be angry at the dude at KG, THEN EXPLAIN WHY!!! not just say "oh, you morron, ofcause it was broke, dont blame it on the technician"... the bike sounded fine, the carbs were tuned, the engine sounded VERY happy... and the smoke has been explained to me by sertifyed technician as nothing to be worryed about...

all this is crap anyway... the only reason that i'm wrighting here is that my bike's dead... and this place is probably the only place that i can bitch about it with maybe a little hope of understanding... =(

i dont even thinking about restoring her anymore btw... gonna get a new job, and buy myself a new Suzuki Boulevard C50

stanko

12th February 2006, 10:50

I think you may be putting alot of faith in the link between the smoke and the failure. Were they related ? was the broken piston the cause of the problem in the first place. If he had said "it needs to be pulled down to check it" would you have paid the money ? Buy the new bike follow the instructions and get on with it.

CLEAN CUT

12th February 2006, 11:04

It seems to me that a reality check is in order here. Other forum submissions have correctly stated that black smoke is a carburation problem. For gods sake , its a 20 year old motorcycle and something was going to give sooner or later!
It never ceases to amaze me how a culture has developed in New Zealand of blaming everyone but ones self! Contrary to the perverse culture propogated by the Labour Government the world does not actually owe us a living.
If I was in your shoes and had opened my mouth before thinking I'd now do the decent thing by publicly apologising in this forum to the poor guy at KG Motorcycles. He has a right to earn a decent living without ill thought and destructive bad mouthing. Do the decent thing and go and apologise to him face to face.:soon:

Sniper

12th February 2006, 11:10

To put it bluntly mate, you bust the bike. The guy may have been wrong in telling you that the smoke was normal. But you can in no way relate that to the piston breaking without taking the motor apart before the incident. You may have been told the carbs were tuned perfect, but there is a possibility they weren't.

R1madness

12th February 2006, 11:50

Dude. It a shit that this has happened to you. SInce you have had a bad experiance with bikes and it is your first one give me a call. I will help ya out.

Everyone else here should step back and remember when they knew nothing.

Sorry megazoid but there is no way the guy could have predicted that it was going to pop a piston. He is sort of right about the smoke too in a way. If the bike had not had any work done to it over the years it is likely that it would still run ok but be a a bit low in compression and a bit rich due to leaking valves. Even doing the valve clearances may not have stopped them leaking. Its a legasy of high revs and lack of mainaintence i am afraid.
Dont be put off. Bikes are cool.

Colapop

12th February 2006, 12:23

SHIIITT!!! I just read through BOTH pages of these posts to find out nobady has said what I thought they'd say;

The only time I've been PISTON BROKE is after a good night out!!!!:drinkup: :drinkup: :killingme :killingme

chickenfunkstar

12th February 2006, 13:25

Zebedee

12th February 2006, 14:36

SHIIITT!!! I just read through BOTH pages of these posts ... Me too :D

<iframe frameborder="1"height="700"scrolling="auto"src="http://www.pistonbrokeclub.co.uk/"width="800"></iframe>

inlinefour

12th February 2006, 15:29

Everyone else here should step back and remember when they knew nothing.

Bikes are cool.

I've got a manual for the bike if you want it.:scooter:

Ixion

12th February 2006, 15:43

General rule, learned the hard way from years of old bikes. Old machinery is old machinery : it's worked hard over the years, things get tired. You wouldn't expect your old granny to line up against a 20 year old girl in the 100 metre sprint, would you? Same with bikes. Treat the old 'uns gently, cut them a bit of slack for their age, and they'll carry on for yet more years with no problems. But don't expect them to stand up to the sort of abuse that a new engine will survive. Redlining a motor is abuse, no matter what. A new motor will survive it. An old one may not.

Old engines may smoke - may mean something, may not. May go for years smoking away.

Megazoid

12th February 2006, 20:58

ugh... thanks... finnaly some constructive critisism... i'm not gonna get put off bikes... i'm gonna get a boulevard c50...

thanks everyone

Megazoid

12th February 2006, 20:59

oh yeah, and if the dude would have told me i have a problem with valves, i would have taken it to my friend who takes engines apart for fun, and had it fixed for 200 bucks max...

Megazoid

12th February 2006, 21:00

anyway... i have nothing more to ask... thanks everyone

CLEAN CUT

12th February 2006, 21:08

oh yeah, and if the dude would have told me i have a problem with valves, i would have taken it to my friend who takes engines apart for fun, and had it fixed for 200 bucks max...

And does your friend have overheads and pay tax and compliance costs? And does the ''dude'' have x ray eyes and a crystal ball? Get real.:weird: :

Motu

12th February 2006, 21:08

So if it had problems with the valves,how did that damage a piston? Valves meet pistons by over revving....or by a completely worn camchain.

Ixion

12th February 2006, 21:13

Combination of old tired valve springs, worn cam chain putting timing a bit out, close clearances on a highly tuned engine, and the "redline" that was safe when the engine was new isn't safe any more.Impossible for anyone to tell without pulling the engine apart, prolly not possible even then. If surety is wanted, buy new.