will turn over but won't start and makes loud banging sounds

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charlie zxr
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My Bike: Kawasaki ZXR400 L9

will turn over but won't start and makes loud banging sounds

Post by charlie zxr » Sat Jan 22, 2011 7:45 pm

hi,
got a ZXR400 L9 and it has been running alright since iv had it.
but lately its not starting. i did run out of petrol but it seemed fine after that and that was a few months ago.
it wont start but turns over and back fires and pops around the engine and exhaust. iv done an oil change and filter change and also put a new reg-rec on it
any ideas guys?

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Mori Man
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Re: will turn over but won't start and makes loud banging sounds

Post by Mori Man » Sun Jan 23, 2011 2:20 am

1) You've sucked sludge into the carbs but unlikely with the inline filter.

2) Valve gap is needing adjusted and was well over due and just a coincidence with your running out of fuel.

3) CDI has a fault or part os the ignition system , pick-up , pulsar , coils or bad earth.

If squooshing "quick start" or the likes directly into the carbs doesn't get it running chances are No.2 fault, if after adjusting and still doesn't run refer to No.3

If the bike catches then dies out again chances are No.1 so remove carbs , strip and clean , replace filter and try again

But never rule out spark plugs so replace them with a new set to start with !!

MM!
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Living life on the edge, SuPposedly

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greenmachine
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Re: will turn over but won't start and makes loud banging sounds

Post by greenmachine » Sun Jan 23, 2011 6:56 am

charlie zxr wrote:hi,
got a ZXR400 L9 and it has been running alright since iv had it.
but lately its not starting. i did run out of petrol but it seemed fine after that and that was a few months ago.
it wont start but turns over and back fires and pops around the engine and exhaust. iv done an oil change and filter change and also put a new reg-rec on it
any ideas guys?
Dont know if this is any help but it might be I just went through the same trouble after my sat for two years when I put it back together it refused to run, It took me a week of trying everything to get it running I had spark and fuel but just kept flodding and backfiring and shooting flames out the exhaust.

I also learnt that you can stuff new plugs in less than a minute by them flooding with fuel, they will still look fine and still spark but when placed under commpression the goes weak and yellow and just starts going everywhere and firing at the wrong time I know this cause it happened to mine.

As moriman said maybe clean your carbys I was told a cheats way to clean without taking them off, drain all the carbs of fuel do up the drain screws fill the carbs up with carby cleaner through the fuel line and leave overnight drain the next day and try steps below but make sure you get the carb cleaner out by running fresh fuel through with the drain screws open to get it all out of the bowls.

also tried aerostart and "start ya b#stard" with no luck, took it to the bike shop and he could not get it started either this was his solution

1) dump all the premium unleaded I had in my tank
2) drain all the carbys
3) put fresh standard unleaded in the tank and leave the drain screws open bit for now
4) turn to prime let the fuel run out of the bowls to get out any leftover or sediment and tighten drain screws
5) take the plugs out and crank the bike for 5 or 10 seconds with know choke or throttle
6) replace plugs with new ones
7) leave bike sit for a few minutes for vapour to settle and disappear so you dont blow yourself up and then start your bike hopefully

Now heres the strangest twist to all this after I got the bike home on the trailer and was going to do what I just told you I tried one thing no one probably ever think to do when trying to run there bike,
after I got back I still had the number 1 plug out of engine and coil lead just hanging so no compression or plug at all in number 1 cylinder, I tried to start it just for the hell of it and what do you know it just started right up on three cylinders with one open bore took it for a ride down the street on 3 cylinders came home put one of my spare back in number cylinder started her up and had no troubles since.

shocking Bizzare but it worked the only I could think was less compression for the starter motor and harder to backfire cause it only had three plugs in it shocking shocking

:smt002 Good luck and keep us posted how you go :smt002

charlie zxr
Posts: 27
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My Bike: Kawasaki ZXR400 L9

Re: will turn over but won't start and makes loud banging sounds

Post by charlie zxr » Sun Jan 23, 2011 10:52 pm

the bike will start if the bike is bump started. does that mean anything else to you guys?
cheers for your help so far.
im abit of a newbie at this aswell so not confident on what im doing.
bike - Kawasaki ZXR400 L9 - turns blue at night
161 160

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gavinfdavies
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Re: will turn over but won't start and makes loud banging sounds

Post by gavinfdavies » Sun Jan 23, 2011 11:31 pm

If it start on a bump, then maybe the carbs are fine, and it's the starter system that's the problem.

i had a similar problem a month back. I fitted a new hid kit, and heated grips, then rode home (my local bike shop let me use their garage to fit my own parts and do servicing etc :smt007 and i get 15% discount!)... got a mile down road and power began to go. thoughts flash through brain... rev counter - check (ie i've got electrical pwer)... fuel - check, i filled it up earlier... fuel tap - oh buggar! I hadn't re-attached the tap or even attached the damn FUEL LINE! :pmsl luckily i had the tools in the back, so i just sorted it at the road side, cranked it over to get the fuel up through the pump and into the bowls, then rode off for a kfc, then home. Next morning... no start! Engine turned, but wouldn't quite catch. turned again, no luck. I decided that the heated grips must be overloading the generator, so disconnected the non-hid bulb (the hid bulb, at a mere 35w/35w is brighter on it's own than two std bulbs!), charged up the battery, and problem solved.

I think that the cranking to get the fuel through can be enough to drain the battery, so even though its starts after that the engine is warm, and easier to crank. The next morning, with lovely thick oil, there's not quite enough juice to get the engine going. i'd be tempted to try pulling the plug on the fuel pump (apparently these use alot of power) and start it using just what's in the float bowls - i got a mile down the road on just the bowls - then once turn the fuel pump back on. I haven't tried this, but it might work. I'm tempted to wire in an inline switch to the fuel pump to make this easier to try.

The worst thing is, if it doesn't start at once, it'll get harder, since the engine could flood, and the battery will drain. catch 22 eh?
I do 700 miles a week in all weathers including snow, that's roughly 35,000 miles a year, and some weekend warrior biker has the nerve to get out of his Audi at work to tell me to I was riding far too fast in the wet (over taking at 50... fast eh?).

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Re: will turn over but won't start and makes loud banging sounds

Post by TOMY » Mon Jan 24, 2011 9:02 am

I had a similar problem back when it was really cold. Would crank, but wouldnt start and sometimes back fired.

Turned out the battery just didnt like the cold weather, and when it turned warmer, it would start just fine. Charge the battery?

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Re: will turn over but won't start and makes loud banging sounds

Post by cargo » Mon Jan 24, 2011 10:33 am

As my ZXRs are race bikes they do not get started that often especially over the winter months..................................thus I have learned a few tricks.

ANY weakness in the battery will cause poor starting ZXR400 IMHO do not start well unless you have a fully charged battery that is holding it's charge.
A fully charged batery is NOT one you have left all night on a car battery type charger a fully charged battery is one that you hve charged with the correct charger and that has been tested to show that it holds it charge.

While a battery might be healthy enough to turn the engine over it is very possible that it will not be healthy enough to turn the bike over AND give good sparks to get it started once it's below 12.3V or 12.2V....................your bike IME will not start


ZXR400 even with a battery that is at 100% will still struggle to start after a lay up especially if it has been cold.


I have cranked and cranked and drained batteries try to start mine.........plugs in ...................plugs out............ plugs in......... plugs out sometimes it's the next day or more........................

One trick I have learnt is that if you can warm the plugs to the extent that they are inpossible to touch with you bare fingers that will help not easy to do and get all four back in and cranking the stater again but doable....................work out a method that suits you.

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gavinfdavies
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Re: will turn over but won't start and makes loud banging sounds

Post by gavinfdavies » Mon Jan 24, 2011 2:44 pm

During the Operation Barbarosa (The German invasion of Russia in '41) the winter temperatures got so cold that the petrol in the tank engines would freeze solid. To help with the cold starting the germans foud it helpful to light a small fire under the engine, cook their breakfast, then start the engine!
I do 700 miles a week in all weathers including snow, that's roughly 35,000 miles a year, and some weekend warrior biker has the nerve to get out of his Audi at work to tell me to I was riding far too fast in the wet (over taking at 50... fast eh?).

charlie zxr
Posts: 27
Joined: Wed Jun 02, 2010 12:07 pm
My Bike: Kawasaki ZXR400 L9

Re: will turn over but won't start and makes loud banging sounds

Post by charlie zxr » Sat Jan 29, 2011 2:19 pm

put a new fuel filter and sprark plugs in and it fired up straight away, cheers guys!
bike - Kawasaki ZXR400 L9 - turns blue at night
161 160

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greenmachine
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Re: will turn over but won't start and makes loud banging sounds

Post by greenmachine » Tue Feb 08, 2011 12:37 pm

charlie zxr wrote:put a new fuel filter and sprark plugs in and it fired up straight away, cheers guys!
just wondering how come I cant see the pictures.
good to hear you got it running :smt002

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fstarocka
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Re: will turn over but won't start and makes loud banging sounds

Post by fstarocka » Sun Jul 31, 2016 6:41 pm

also having the same issues, new battery, plugs good, cleaned carbs for 2 days - every passage and jet blows clean.. bumped with car and started..

batt full, high pitch swinging - kind of wants to start but keeps struggling real bad..

every now and then it makes an incredible BANG out of the exhaust! like a bomb went off -

tried no choke, 1/4,full - everything :(

starting to think one coil might be bad - cos it was alot hotter than the other one when i got off one day and felt it.

is there a way to test bike spark strength? and where does the green and red wire go? coils have green and black -

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