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 Post subject: Re: RZ 500 electrical problem
PostPosted: Mon Apr 09, 2018 4:23 pm 
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phildu31 wrote:
I also thought about defective venting but assumed there was no spark at all on four cylinders.


Me as well, as it is a well known problem and the symptoms fit, but dismissed the idea because there was no spark indicated.

As an aside; everyone should own an inline spark tester. Leave the plug in the head and install the tester between the plug and the lead. If there is spark, you'll see it.

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1985 RZ500 1GE Spec
1985 RZ500 47X Spec Project Bike
1986 RG500 ATR
1986 NS400R
1987 TZR250
1988 Honda RC31
2007 DL650 VStrom
2014 Triumph Thruxton Modified


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 Post subject: Re: RZ 500 electrical problem
PostPosted: Mon Apr 09, 2018 6:25 pm 
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Thanks fellas. I’ve tried that as well. Thinking I was possibly pulling a vacuum on the tank but that wasn’t the case. I’ve tried to eliminate all possibilities of something electrically getting hot and opening up and breaking the circuitry causing me not to have spark. I am definitely not the best electrically by no means. That’s why I reached out for those of you who are. I’ve checked my wiring harness my ignition coil‘s and grounds my stator coil my pick up coil my source coil my CDI. I’m just at a total loss on what else to check. One thing I haven’t checked is my rectifier but with my weak electrical knowledge I don’t know if that could be a factor with this problem.


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 Post subject: Re: RZ 500 electrical problem
PostPosted: Mon Apr 09, 2018 7:05 pm 
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It can be a very frustrating process. Starting with the main fuse and covering the rest of the system is a lot of work.

It is important that it has clean contacts and a clean ground. Both can affect the output voltage.

If you do want to check it, start the bike and meter the voltage across the battery terminals. Increase the RPM to at least 2000 and measure the voltage. You want to see around 14.5 V. A little more or a little less is good. My experience has shown that 4000-5000 RPM will give you a more realistic reading.

_________________
1985 RZ500 1GE Spec
1985 RZ500 47X Spec Project Bike
1986 RG500 ATR
1986 NS400R
1987 TZR250
1988 Honda RC31
2007 DL650 VStrom
2014 Triumph Thruxton Modified


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 Post subject: Re: RZ 500 electrical problem
PostPosted: Mon Apr 09, 2018 8:11 pm 
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Thank you so much. I will measure the voltage across the battery and see what I come up with their is well.


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 Post subject: Re: RZ 500 electrical problem
PostPosted: Tue Apr 10, 2018 4:06 am 
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Location: Toulouse France
Charging circuit is not involved in ignition on this bike with original CDI.
You could even start the motor with battery removed.
Elements involved are only : source coils, pickup coil, ignition key, kill switch, side-stand control unit for Canadian bikes and CDI.
And of course the 2 ignition coils on output side.
Did you check the side-stand control unit or tried by removing it ?
Last thing that could interfere is the pickup gap but the only way to check it is with an oscilloscope.
The only thing I could recommend is to swap the stator.


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 Post subject: Re: RZ 500 electrical problem
PostPosted: Tue Apr 10, 2018 6:30 pm 
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Thanks fellas. I’m going to keep at it with the recommendations you had given me. I will post my results. Thanks again 👍


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 Post subject: Re: RZ 500 electrical problem
PostPosted: Tue Apr 10, 2018 7:23 pm 
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rz ron wrote:
Thanks fellas. I’m going to keep at it with the recommendations you had given me. I will post my results. Thanks again 👍


The reg/rec is likely fine, but if you do find the regulator-rectifier putting out higher than expected voltage then you need to look at other failures. The excessive voltage will cause other components, like the CDI, to fail.

_________________
1985 RZ500 1GE Spec
1985 RZ500 47X Spec Project Bike
1986 RG500 ATR
1986 NS400R
1987 TZR250
1988 Honda RC31
2007 DL650 VStrom
2014 Triumph Thruxton Modified


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 Post subject: Re: RZ 500 electrical problem
PostPosted: Tue Apr 10, 2018 7:32 pm 
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The original Yamaha CDI is the only electrical component not connected to the +12V from battery/regulator.
Ignition power is given by the coils of the stator.


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 Post subject: Re: RZ 500 electrical problem
PostPosted: Tue Apr 24, 2018 8:50 pm 
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Well I borrowed a stator and pick up coil From a friend of mine and left with the same problem. Thanks to Bill Wilson‘s recommendation I have another avenue to try. I’m going to check continuity from the battery throughout the whole ignition circuit when cold. Then once it gets hot and will no longer start I’m going to check it again to see if there are any differences. I’ve reached the end of my rope with this problem. Unlike anything I’ve ever experienced.


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 Post subject: Re: RZ 500 electrical problem
PostPosted: Tue Apr 24, 2018 9:22 pm 
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It may be worth checking the main fuse as well. A heat related defect there will cause the same problem, and such a heat related defect is not unheard of. The fuse may test fine when cold, but with heat it will fail. Either the fuse, or the holder, or both.

_________________
1985 RZ500 1GE Spec
1985 RZ500 47X Spec Project Bike
1986 RG500 ATR
1986 NS400R
1987 TZR250
1988 Honda RC31
2007 DL650 VStrom
2014 Triumph Thruxton Modified


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 Post subject: Re: RZ 500 electrical problem
PostPosted: Wed Apr 25, 2018 8:12 am 
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Thanks Silverstrom. I have already checked the main fuse and holder along with all the rest of them.


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 Post subject: Re: RZ 500 electrical problem
PostPosted: Wed Apr 25, 2018 9:23 am 
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As said before, battery and fuses are not involved in this ignition.
Elements involved are only : source coils, pickup coil, ignition key, kill switch, side-stand control unit for Canadian bikes and CDI.
Is your bike a Canadian RZ ?


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 Post subject: Re: RZ 500 electrical problem
PostPosted: Wed Apr 25, 2018 12:33 pm 
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Which have all been tested and retested. Perhaps it's time to think outside the box Philippe. Clearly conventional thinking isn't solving the problem. This is the kind of frustrating snag that makes a person want to reach for the gasoline and matches.

Maybe it's time to run a spare wire harness.

_________________
1985 RZ500 1GE Spec
1985 RZ500 47X Spec Project Bike
1986 RG500 ATR
1986 NS400R
1987 TZR250
1988 Honda RC31
2007 DL650 VStrom
2014 Triumph Thruxton Modified


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 Post subject: Re: RZ 500 electrical problem
PostPosted: Wed Apr 25, 2018 3:10 pm 
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Location: Germany
MK wrote:
https://www.reichelt.de/Cold-Sprays-and ... stct=pos_0

If it starts after cooling down, you have a bullet proof evidence.


I didn't read you tried cooling down any other components with the spray?
If you say you ran out of options, then how about systematically cooling down ANY involved devices, plugs, cables, coils ?
Cool down one after another and hopefully one of them will be to blame.

You didn't mention using new plugs and maybe plug caps. Use BR8HIX (or BR9HIX if you riding fast/hard very often.)

What about the HT coils. Have you tried exchanging them?

In very rare cases the tach can drain the energy from the capacitor in the CDI. Unplug the grey cable on the tach and unplug the PV controller (both share the tach signal that'll kill the spark if grounded)

And cross check thrice that it's not the tank vent, i.e. the carbs have enough fuel (try transparent hoses for debugging this one)

And do not waste time with the battery, fuses, Power Valve or charging system. That can be completely faulty and it'll still start & run.

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Martin


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 Post subject: Re: RZ 500 electrical problem
PostPosted: Thu Apr 26, 2018 5:04 pm 
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Thanks for all your help everyone. I’m going to try and look at my wiring harness that’s associated with ignition real closely and check continuity before/after starting failure. Will keep updated.


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