ZXR400 idle/fuel problem

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harrisonjc87
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Joined: Wed Mar 18, 2009 9:35 pm
My Bike: ZXR 400

ZXR400 idle/fuel problem

Post by harrisonjc87 » Sun Apr 19, 2009 2:21 pm

I know very little about bikes......

Think my ZXR400 is running rich?! Smelling lots of petrol, and others can smell it when I'm riding.

Also having a problem with the idle, whether this is because its running rich? The idle will either sit at just under 1000 and then when I ride cuts out when I pull the clutch in to stop, or if I change the idle to about 1500 and then blip the throttle it comes back down to 2500/2000 and doesn't go back to 1500..any ideas why this is?

If I then try to change idle to slightly lower than its sat at it falls to under 1000 and cuts out sometimes....totally stuck...thinking of taking it to get looked at as not very bike mechanically minded...but thought I'd see if anyone had any ideas on here first?!

Jeppo
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Re: ZXR400 idle/fuel problem

Post by Jeppo » Sun Apr 19, 2009 3:34 pm

The dying when you stop indicates a rich mixture. Check ure exhaust pipe, if its rich there will be thick black soot all around the edge. You need to adjust the mixture screws on the carbs.

As for the hanging revs, this usually means there is an air leak somewhere. Check the airbox is correctly fitted and there are no silly gaps between it and the carbs. I'm assuming this is your first bike? Get yourself a manual and work through the problems, these are very easy bikes to work on!

I'd get the rich mixture figured out coz it wastes petrol and bogs the bike down a bit, much more fun to ride with sorted carbs.
The hanging revs are pretty common and not a large problem, mine does it.

lewisdale
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Re: ZXR400 idle/fuel problem

Post by lewisdale » Sun Apr 19, 2009 7:51 pm

whats the easiest and best way to get the mixture right then? my end pipe is sooty as fook

harrisonjc87
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My Bike: ZXR 400

Re: ZXR400 idle/fuel problem

Post by harrisonjc87 » Mon Apr 20, 2009 7:23 am

Don't know if this helps..... When the fuel switch is set on Fuel on, its running like I first explained. But when I change it to reserve its absolutely fine!!

Since I first picked up the bike about a month ago the switch has been on reserve, the other day I thought I should really turn it to Fuel on then if it runs out I have reserve to use.

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MillaMeter
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Re: ZXR400 idle/fuel problem

Post by MillaMeter » Mon Apr 20, 2009 10:55 am

harrisonjc87 wrote:Don't know if this helps..... When the fuel switch is set on Fuel on, its running like I first explained. But when I change it to reserve its absolutely fine!!

Since I first picked up the bike about a month ago the switch has been on reserve, the other day I thought I should really turn it to Fuel on then if it runs out I have reserve to use.
Hi,

What model is your ZXR400? In the earlier ZXR models I know that Mr Kawasaki made some really shite ideas and 1 of them was the inlet manifolds. They work first of all but over the years keep going hot cold hot cold hot cold, the rubber deforms and starts to leak air coursing these problems! What I suggest is to take the tank off, and the airbox, hook the tank back up to the main fuel line, get a mate to hold the tank for you while you spray carb cleaner around the inlet manifolds. (they're the black rubber tubes that the carbs bolt onto) If the engine bogs down and sounds like it's gonna cut out, you've got an airleak. You'll have to then take the carbs off, unbolt the 2 bolts that hold each manifold on, and you can either 1. replace with new 1s from Mr Kawasaki (~£80) or you can seal them up with a bit of silicone sealer (~£3)

Regards

Rich
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ZXR400s 4eva! I miss mine already :(

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wildcat
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Re: ZXR400 idle/fuel problem

Post by wildcat » Mon Apr 27, 2009 9:22 pm

MillaMeter wrote:
harrisonjc87 wrote:Don't know if this helps..... When the fuel switch is set on Fuel on, its running like I first explained. But when I change it to reserve its absolutely fine!!

Since I first picked up the bike about a month ago the switch has been on reserve, the other day I thought I should really turn it to Fuel on then if it runs out I have reserve to use.
Hi,

What model is your ZXR400? In the earlier ZXR models I know that Mr Kawasaki made some really shite ideas and 1 of them was the inlet manifolds. They work first of all but over the years keep going hot cold hot cold hot cold, the rubber deforms and starts to leak air coursing these problems! What I suggest is to take the tank off, and the airbox, hook the tank back up to the main fuel line, get a mate to hold the tank for you while you spray carb cleaner around the inlet manifolds. (they're the black rubber tubes that the carbs bolt onto) If the engine bogs down and sounds like it's gonna cut out, you've got an airleak. You'll have to then take the carbs off, unbolt the 2 bolts that hold each manifold on, and you can either 1. replace with new 1s from Mr Kawasaki (~£80) or you can seal them up with a bit of silicone sealer (~£3)


Regards

Rich
gotta admit, this post have helped me out loads :smt003
had probs with this for as long as i can remember :smt017
decided to give my bike a good service, and while it was apart dedcided to have a quick peek on here and hey presto :excited :excited :excited, came across this and decided to do this little test and found out that thats exactly whats going on wiv my iccle zxr :smt003 , my dad gonna sort it 2moro :excited :excited :excited :excited :excited
thanks alot :smt003

Jeppo
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Re: ZXR400 idle/fuel problem

Post by Jeppo » Mon Apr 27, 2009 9:37 pm

Cheers rich, mine does this to but i assumed the air leak was between airbox and carbs! May aswell sort this problem out while bike is stripped bair and forkless lol.

harrisonjc87
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My Bike: ZXR 400

Re: ZXR400 idle/fuel problem

Post by harrisonjc87 » Wed Apr 29, 2009 11:51 am

Seem to have it running sweet now.. stripped it back at the wknd and found one of the carbs were loose....which was where the smell of petrol was coming from...everything seems ok now...put 150 miles on it already with no problems...off out today to stick some more on and enjoy the sunshine!! Thanks everyone for the ideas!!

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fstarocka
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Re: ZXR400 idle/fuel problem

Post by fstarocka » Wed May 25, 2016 10:38 am

fyi - a vaccum leak wont be on the airbox side but between the carb and engine.. so the airbox will do nothing to show this.. the airbox only cleans air with the use of a filter..

I bought fuel resistant rubber and cut out the shapes of the intake manifolds - all 4of them were the same.. punched out the 2 holes and basically screwed the intake down ontop basically making a permanent (for now) seal - since the leky rubber boots are a good 4mm away from the edge, theres plenty of rubber there now to seal it up.

and it cost me 2 quid for a huge sheet and I must have used 5%.. so a few pence then..

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