[druk]

My bike is a KLE 500 92', I think this model is not available in the USA, but you can think of it as an EX500 or GPX, more or less (are these available in the USA?).

This bike is almost new, just 28,000 miles.

The thing is the second cylinder quits INTERMITTENTLY, and I've had the carbs cleaned and adjusted to no avail, so I'm suspecting an electrical failure.

Spark plugs are new, and the igniter coil is OK because I put it in place of the other coil (cylinder 1's) and it works fine.

What I'd like is to rule out the CDI box. How can I do that myself, if possible?

Also, how can I rule out the pickup coil?

Let's say for one moment that the electrical part is ok. What else could it be? What could the mechanic have missed in the carbs? Could it be valve-related?

Remember that this problem is intermittent. Once the cylinder gets going, it won't quit until I stop the bike for some time, and then when I start the engine again, it may or may not quit. Although I can't be sure if the cylinder is fully working when it gets going, maybe it's working on a low spark.

Could it be that the cylinder floods and quits until it dries up?

All ideas are welcome, I kinda desperate right now.

 

[ZX Kawboy]

It's a rather vague description of the problem, but I'd suspect an electrical problem, to be sure.

Remove both coils and test them to make certain that they're within specification. After that, work down the list. Check your spark plug wires (arcing can sometimes cause what you've described) and if neccesary, replace them. While you're at it, replace the spark plug boots.

Failing that, test your CDI box, again, making certain it's within specification.

If none of these are the problem, I'd be surprised. And No, for the record, I don't think your carburetors were mis-adjusted.

 

[druk]

Thanks a lot, I'll give that a try.

 

[cjiom]

Ignition Problems?

druk,

Do you have a Haynes manual or a wiring diagram? This may give you a few pointers.

I have had some ignition problems with a GPZ500S D (EX500D) I would start with ZX's suggestions. Unless you have some posh test equipment its a case of working through things and ruleing them out. Start with the simple stuff.

The EX500A and EX500D/ER500 have slightly different ignition systems and I don't know which the KLE is fitted with. The EX500A (up to 93) has two pickup coils where as the EX500D (94 on) has just one and I believe it works on a wasted spark principal (fires every time the piston is at the top of its stroke).

The EX500D has 2 wires going to the pickup coil, the EX500A has 4.

Do you know which type is fitted?

If there is only one pickup coil then I would not suspect the pickup coil as one cylinder is working correctly.

If you have a tacho (rev counter) does it work normally when you have the problems? If it is like the one fitted to the EX500D it is driven from the CDI unit. A problem there would indicate a issue with the input to the CDI box or the CDI box.

The EX500A appers to have a tacho driven from the feed to one of the coils. (Cylinder 1) Appears to only be some models with this arrangement, some A models have a seperate feed.


I've had problems where I suspected were my CDI unit but they turned out to be an intermittent short in the wiring loom. Although I have read on ebay people saying the CDI units are "prone to packing up" people not selling them as spares seem to think they are very reliable. Also their opinion was that they either fail and stop working or work fine. Intermittent faults are "rare". Haynes says the main way of testing a CDI is to swap it for a known good unit. Not that easy to do unless you have a spare. They are not cheap :-( Keep an eye out for one though you may find one on ebay going cheap.

You say turning off the ignition clears the problem? How long do you have to wait? Quickly switching off and back on while riding doesn't solve the problem (temporarily) does it?

 

[druk]

Re: Ignition Problems?

You've made some very interesting comments, thank you very much.

Believe it or not, the culprit was some lint in the carb corresponding to the affected cylinder. The mechanic took out the mix screw, flushed some compressed air into the hole, put it back, and everything was instantly back to normal.

By the way, the KLE has only one pickup coil (one pair of wires, and only one coil showing in the diagram.

Thanks all, guys.

druk,

Do you have a Haynes manual or a wiring diagram? This may give you a few pointers.

I have had some ignition problems with a GPZ500S D (EX500D) I would start with ZX's suggestions. Unless you have some posh test equipment its a case of working through things and ruleing them out. Start with the simple stuff.

The EX500A and EX500D/ER500 have slightly different ignition systems and I don't know which the KLE is fitted with. The EX500A (up to 93) has two pickup coils where as the EX500D (94 on) has just one and I believe it works on a wasted spark principal (fires every time the piston is at the top of its stroke).

The EX500D has 2 wires going to the pickup coil, the EX500A has 4.

Do you know which type is fitted?

If there is only one pickup coil then I would not suspect the pickup coil as one cylinder is working correctly.

If you have a tacho (rev counter) does it work normally when you have the problems? If it is like the one fitted to the EX500D it is driven from the CDI unit. A problem there would indicate a issue with the input to the CDI box or the CDI box.

The EX500A appers to have a tacho driven from the feed to one of the coils. (Cylinder 1) Appears to only be some models with this arrangement, some A models have a seperate feed.


I've had problems where I suspected were my CDI unit but they turned out to be an intermittent short in the wiring loom. Although I have read on ebay people saying the CDI units are "prone to packing up" people not selling them as spares seem to think they are very reliable. Also their opinion was that they either fail and stop working or work fine. Intermittent faults are "rare". Haynes says the main way of testing a CDI is to swap it for a known good unit. Not that easy to do unless you have a spare. They are not cheap :-( Keep an eye out for one though you may find one on ebay going cheap.

You say turning off the ignition clears the problem? How long do you have to wait? Quickly switching off and back on while riding doesn't solve the problem (temporarily) does it?

 

[cjiom]

Fantastic, goes to back up the simple stuff theory

I find it comforting to see other guys with 60k+ on their EX engines and still riding etc

 

[druk]

Fantastic, goes to back up the simple stuff theory

I find it comforting to see other guys with 60k+ on their EX engines and still riding etc

Now that you mention it, how many miles do you think one of these engines could last? I find them very sturdy, they don't really seem to deteriorate. Of course, I treat her very gently, but what do you think?

 

[cjiom]

Well mine has 28,000 and a bit on it.

I have seen several GPZ500Ss for sale with silly mileages on them. Well over the 60k mark. 72k rings a bell from somewhere.

From what I have read if you keep up the oil changes they do last well. The only downside is that if anything did go on a high mileage unit it would probably be better to throw it away than pay the stupid prices Kwak want for parts.

The Haynes manual seems to say that most of the engine and gearbox is pretty good for a rebuild when it gets worn too, cylinder liners can be replaced, etc. I seem to remember reading that the cam shaft bearings are part of the head and are not replaceable but that they thought a good engineering firm could probably sort them anyway. Could double check that if important but fingers crossed you won't ever need to.

I'm not expecting any big bills in the near future

Somewhere before I bought mine I read something about the flywheels being a problem. I believe that the design was modified to get round this.

Also another person wrote that you must not run them on the sidestand as one of the bearings drys up and can get damaged. I've never confirmed this though one of my friends thinks he has heard of the problem. Perhaps someone on here can comment.

I don't leave mine idling on the side stand, if I was going to warm it up I'd use the centre stand or sit on it, gets round that problem anyway.

Of course lots of what you hear on the net is complete bo****ks so unless you can confirm that stuff or it comes from a reliable source you have to take it with a pinch of salt.

Personally I am very happy with my second hand GPZ and find it to be a good strong engine. I learnt to ride on a ER that had done 30k in a riding school. That's not an easy life and they were running sweet. Got to be a good recommendation!

What do other people think?

Any tips for keeping them running longer?

 

[ZX Kawboy]

I have an American version (EX500/Ninja500) with 88,000 on it. This is an engine that seems to live forever, and I love it. I'm about to tear down the motor and build a racebike out of it. We'll see how it goes.

Cheers

ZX