ZXR 400 Cutting Out

[JayC]

Hi guys I'm new here and new to biking! I've had my ZXR 400 L1 1991 model for a month now but it's spent most of that time off the road. I'm hoping someone can help me.

I'll start from the beginning. The bike initially broke down with various issues all at once -it had a flat battery, a burnt out fuel pump relay, broken fuel pump, blown bulbs (tail, headlights, neutral indicator and rev counter bulbs) and the rev counter no longer works.

Since then in an attempt to get the bike running I have replaced the regulator/rectifier, new battery, new fuel pump relay, new fuel pump, replaced the bulbs, new coils and leads, fresh oil and petrol.

The bike will now start with the choke and and run for a short while before cutting out/ stalling. Sometimes it will idle for a while and get to temperature before stalling, sometimes not very long at all. The battery does seem to be charging.

If anyone can suggest reasons and possible solutions for this problem I would be very grateful. I'm not a mechanic but willing to give anything a go to get it running!

Thanks!!

[JayC]

I guess your all as stumped as me?

With more of a chance to test it the battery does seem to be charging intermittently and has run flat.

With a multimeter on the battery it will sometimes sit at 12.5v at idle up to 14v+ when rev'd.

Other times it drops to 11.8v at idle before stalling.

[acergremlin]

Have you checked the wiring going to the regulator to because with that much electrical gear gone wrong together that could be the problem. Failing that it does sound like the CDI is breaking down when getting warm, not sure with your bike but the rev counter normally gets its signal from the CDI also but the only real test for the CDI without kawasaki testing equipment is to replace it with a known working one.

[JayC]

Hi thanks for your post.
The charging problem was down to the ignition switch. The switched live going to the regulator wasn't making a good connection and so charging was intermittent. As a temporary fix a dab of solder on the connections worked.

What's left is a fueling problem. The bike will cut out when given a short burst of revs. This can be overcome by hooking the fuel pump up to a permanent power source.

Any suggestions as to why the bike isn't getting enough juice under normal conditions?

[JayC]

It turns out that the new fuel pump relay I had bought was dodgy. The fuel pump only had power when pressing the starter switch but not whilst idling. This starved it of fuel when rev'd!

[beano4390]

Hi
This probs is too late now and no one will see this but anyway...

I've got a ZXR400 H2, and it has a running problem.. i was riding the bike home from work most of the roads are dual carage ways all was fine until i came to a junction. i slowed down as usall and came to a stop, and my bike cut out. Hit the starter and it started fine but went to pull off and it was really juddering and didn't want to go... i set off again anyway and once revs are above 4grand bike runs fine... again come to a junction and the same happened the revs drop to about 1.5 grand and the bike cuts out.......... When i finally got the bike home it cut out again surprise surprise. i got the bike in my garage and up on paddock stands started it up and left it to idle and it ran revs where up and down but it ran.. i gave it some throttle took revs to about 6 grand let them off again slowly and the bike cut out........... if i leae the bike to idle and don't touch the throttle it will run, but as soon as i give it revs and then let it go to idle it dies................. HELP ME

[QKENUF4U]

JAYC thanks for the imput........just learned some new things by you posting what you found as the problem (im a bike tech and that was great info)

beam - sounds like you may have float height/level problems....... maybe check your fuel level in the floats and see if its low........ also make sure your bike is charging correctly also.........

[beano4390]

Hey

qkenuf4u - thanks for that i will have to have a look at the levels later and see.. Bike is annoying me thou cause i have started it today and taken it for a ride was out for atleast an hour and it hasn't cut out once, revs where still up and down slightly but it never cut out. As far as i know the battery is fine it recently had a new battery cause previous owner let it stand. i had a garage do the battery and the restrictor kit at same time and they said it was ok but this was like a month ago it might have chnaged...... I will try and have a look at the levels later if it not to dark when i get home from work......

Anyone else got any idea's of what to check... Btw it has had a service since i have owned it and so filters and plugs have been changed so i don't think these are the causes............. HELP ME SOME MORE PLZ !!!!!!




P.s anyone no if the exhaust headers of a L Model zxr400 will fit a H-Model.... i no the attachment for the can is slightly different but i just wondered if the headers would fit as i am looking into changing the system as it still has the standard on and it looking a bit worse for wear lol and i can't seem to find anywhere / anyone who makes the headers for the H-Model everywhere say to fit 91 -00 (L-Model) ..................