stator or not

[500.FLETCH]

Morning All

its seems that after about ten mins or so the top cylinders stop firing
is this a stator issue.it starts fine?
but once cold they work again any ideas?

many thanks
Fletch

[MK]

On a 350 that'd sound like source coils.
Secondly it could be the CDI.

But there's an easy fix : Get a decent DC CDI which will get rid of both at once AND adds you around 10 ponies.
Though there are people who run an Ignitech on their RD500, I'd recommend a Zeeltronic here.
(Because I had issues with 3 different RD500's using an Ignitech but none with a Zeeltronic).

Note that you need a PDCI (that works on 12V) and NOT a PCDI (which requires working source coils)!

[phildu31]

If you have one bank still firing that's definitely not the source coils nor the stator.
That leaves you with a faulty CDI or the HT coil or even only one spark plug wire cut as the two plugs are serialized.

[MK]

Ups - over-read that the lower bank runs!
That leaves HT coil, cables and CDI as main suspects.

[silverstrom]

The hot-cold thing sounds like a CDI cold solder joint. It works until it gets hot and breaks the circuit. It cools down and once again completes the circuit and starts working again.....until it gets hot. This is a common problem with the first generation RZ350 CDI. I've never heard of it with an RZ/RD/RZV500 CDI. Swapping in a different CDI will be the only way to test that possibility.

Coils will do something similar. You can check that theory by swapping coils. I would expect an HT problem should be there from the start. You can cut 5 mm from the HT lead ends and then reattach to the coil and plug cap. That will give you a known good connection at both ends.

[JonW]

...Get a decent DC CDI which will get rid of both at once AND adds you around 10 ponies.
Note that you need a PDCI (that works on 12V) and NOT a PCDI (which requires working source coils)!

Martin, Is that +10 nags on an otherwise standard bike, ie OEM carbs and pipes?

[silverstrom]

...Get a decent DC CDI which will get rid of both at once AND adds you around 10 ponies.
Note that you need a PDCI (that works on 12V) and NOT a PCDI (which requires working source coils)!

Martin, Is that +10 nags on an otherwise standard bike, ie OEM carbs and pipes?

Took me a minute to get the +10 nags reference.

[MK]

Yep, but with a decent advance curve and optimized PV actuation.
I have more dyno-data for 350's but there it's around up to +4kW for ignition only and up to +3kW for PV only.

That's why I don't hesitate to use DC CDI's whenever there's the slightest chance of the source coils or the CDI to be faulty.

[JonW]

...Get a decent DC CDI which will get rid of both at once AND adds you around 10 ponies.
Note that you need a PDCI (that works on 12V) and NOT a PCDI (which requires working source coils)!

Martin, Is that +10 nags on an otherwise standard bike, ie OEM carbs and pipes?

Took me a minute to get the +10 nags reference.

Ahh sorry, Er... I was just broadening vocabulary for the forum?! lol

[JonW]

Yep, but with a decent advance curve and optimized PV actuation.
I have more dyno-data for 350's but there it's around up to +4kW for ignition only and up to +3kW for PV only.

That's why I don't hesitate to use DC CDI's whenever there's the slightest chance of the source coils or the CDI to be faulty.

Thanks Mate. I was thinking of having my bike tuned here by a guy who knows the Zeels and didnt realise that could add 10bhp to a 500, Its tempting to do that as the mod is reversible and invisible etc. My bike is a resto so want to keep it mostly standard etc.

I have Zeels on one of my 350s and my 421 already.

[500.FLETCH]

Hi guys
sorry for late reply and many thanks for all the reply's
ok so I have changed coils+leads
still happens so need a cdi box? so where can I get one of them?

many thanks

Fletch

[phildu31]

So, if possible, try a swap with a good CDI if available : either swap the good CDI on your bike, or swap your supposedly faulty one on another bike.
Just to confirm.
Once done, best option would be to go with a Zeeltronic CDI/YPVS one.

[silverstrom]

Hi guys
sorry for late reply and many thanks for all the reply's
ok so I have changed coils+leads
still happens so need a cdi box? so where can I get one of them?

many thanks

Fletch

A little more info will help your search.

Which do you need...47X or 1GE? And where are you located?

[500.FLETCH]

Hi Silverstrom
47x location uk unable to swap onto another bike.
or I could send it to a forum member to check it out for me

[silverstrom]

Hi Silverstrom
47x location uk unable to swap onto another bike.
or I could send it to a forum member to check it out for me

I have a spare 47X here if you can't find something closer.

Did you swap coils to see if the fault followed the swap?