Kawasaki Sportsbike Riders Club - Australia - Online Forum

Hi all,

I come asking for some help with diagnosing a problem with my bike. I've got too many things in mind and maybe someone with some experience with this issue might know!

I have an '89 ZXR250 which is giving me some starting issues.

Background info:
*valves done around 2 years and unknown kms ago, (assumed between 25-30,000km)
*Battery is good and charging system is working well
*Plugs changed 1 month ago - when the bike starts it runs much smoother, but did not solve the starting issue
* I have noticed cracks in the leads and the leads are getting hard, but this hasn't caused issues so far
* I have a petcock which isn't flowing in the ON and RES positions, but is flowing fully in between them, and I have also checked the fuel filter for blockages. Fuel is flowing properly with the bike stationary.

Problem:

Bike will start perfectly with some choke when cold, once I ride the bike to operating temp it will run perfectly and behave exactly the way I want it to.

When I turn the bike off when it's at operating temp I can restart it on and off constantly and easily (though it does turn over a fair few times and require a little throttle to start, which it didn't need before). But if I try to start it again after 30 seconds it refuses to start. I just keeps turning over very fast and ALMOST starting but just doesn't.

The only solution I have had so far for this is to bump start the bike, and that works every time. It does however feel like the bike is bogging down for the initial 10-15 seconds after it kicks over.

If I leave the bike to cool, it will start back up again with choke and a few turn-overs.

Wtf is going on? I am now thinking compression is low, 2 years ago I was getting 150 in 1,2 and 4 cylinders and 140 in cylinder 3.

Thanks for the help!
Aj

Battery on way out, or valves too tight

I'll put in my 2 bobs worth.
If it's the carbs, pull them off & clean them out, buy some carby cleaner & spray all the holes & jets just in case.
What comes to mind is maybe the choke is on a little bit, check the cable tension, if all that's good then there still may be a choke leak so block them off with some gasket paper or a rubber stopper that won't leak & see if the issue persists.
It'll be an elimination process.
Another trick is to unscrew the plug cap off the lead & snip about 10mm off the end then screw the cap back on, won't hurt to tidy them up anyway, they sound pretty old & heat affected.
Could be a little bit of a few things, the more things you try the better it'll get & same with you.
Good luck, it's all part of the pleasure of owning a bike

From memory the fuel petcock works off vacuum from intake? Should be a small hose going to the petcock if it does.....

I'd be checking the valve clearances.
If they are in spec then look at carbs, check for blocked pilot/idle jets, fuel air screw settings and float heights in-particular
Post up your findings.

Cheers, Tim

Hi I have a problem with my zxr250 I cleaned the jets and put it all back the way it came off and now I can't get fuel into the carbs sometimes when I put on full choke and on prime it idles for a minute then dies.

Does anybody know what is causing the blocking of fuel

Thanks