Laverda 500 not charging

michipons

michipons

Hero member
Location
Palma de Mallorca
Hi all, Hi Rob :D

today a friend called me to help him to find out why his battery is apparently not charging. (Why he called me? because his elec knowledge is even worse than mine)

It is a Laverda 500, with this Volt regulator (see photo), I am not familiar with this kind of regulators. In my mechanical regulator, I could open it, understand it and fix it. But no idea how this one works. What are the necessary checks to detect the faulty item?

I have checked the voltage output at the end of the two cables from the generator, (yellow and black/yellow) they are producing peaks up to 40 Volts AC, when I put the voltmeter in the exit of the regulator, touching it on one side and the other one to earth, I only get a reading above 12 volts DC beyond 4000rpm's, when all is connected and I touch + and - in the battery, the voltage is constant to 12.6V, which is also the Voltage when the engine is stopped. We have tried two regulators (both original bosch) one of them illuminates the red light steady, the other one, keeps the red light always off :-\ The rest of the indications are similar...

May be both regulators are broken. So, how do I perform the checks correctly to know what is faulty and what is not?

Regards,
Miguel.

IMG_6425.JPG
 
that's an original rectifier/regulator, no longer available, 40 years old plus and probably  both of them are duff, simple fix is to get a replacement single phase reg/rect, it will be smaller than the stock one and you will have to drill one extra hole in the mounting plate (not easy as space is limited and a 90 degree chucked drill will be needed. they are available from Electrexworld and Rex's speed shop, but to get one with an extra wire to "drive" the red light will be very hard,
Bradders will tell you where to get that (much more) expensive item , he got one for me at the same time as he was buying one for himself.
Checko, I think, maybe, not sure.
CLEM
 
CLEMTOG said:
that's an original rectifier/regulator, no longer available, 40 years old plus and probably  both of them are duff, simple fix is to get a replacement single phase reg/rect, it will be smaller than the stock one and you will have to drill one extra hole in the mounting plate (not easy as space is limited and a 90 degree chucked drill will be needed. they are available from Electrexworld and Rex's speed shop, but to get one with an extra wire to "drive" the red light will be very hard,
Bradders will tell you where to get that (much more) expensive item , he got one for me at the same time as he was buying one for himself.
Checko, I think, maybe, not sure.
CLEM
Click to expand...

Hi Clem,

Thank you, as there are over 200 reg/rec, I will send them an email to recommend me the most appropriate. Who is Bradders?

Actually would be great to find 2 of those rec/reg that can drive the red light, as I could fit one of them in my 3C, when changing the rectifier, and activate the red light

regards,
Miguel.
 
Those original rectifiers are not very reliable.

The one on my ex wife's 500 died, the one on my new wife's 500 died.
Replaced by an Electrex item with provision for the charging light.
Put it in the tail piece of the bike on a metal plate for heat dispersion.

Paul
 
Paul Marx said:
Those original rectifiers are not very reliable.

The one on my ex wife's 500 died, the one on my new wife's 500 died.
Replaced by an Electrex item with provision for the charging light.
Put it in the tail piece of the bike on a metal plate for heat dispersion.

Paul
Click to expand...

Hi Paul,

could you specify which model did you buy and where??

Thanks,
Miguel
 
Still I am assuming that is the regulator that fails (most probably) however I have not an strong confidence in my diagnosis, so would be great to know how to perform the test properly :D
Miguel
 
michipons said:
I have not an strong confidence in my diagnosis, so would be great to know how to perform the test properly :D
Click to expand...

Hi Miguel

You've already tested it. Your measurement of the AC input and DC output voltage is the definitive test.
You have AC input to the regulator but no increase in system voltage when you rev the engine. That confirms that there's no output from the regulator.  I think your diagnosis is good.
 
michipons said:
Hi Paul,

could you specify which model did you buy and where??

Thanks,
Miguel
Click to expand...

I bought an Electrex RR51

https://www.electrexworld.co.uk/cgi-bin/ss000001.pl?page=search&SS=RR51&PR=-1&TB=O&ACTION=Go%21

I presume that I used the model for the Atlas.

Paul
 
The type of regulator/rectifier fitted is a single phase device.  This Electrex video explains how to test a three phase reg/rect ... but the principles are the same. 
This Electrex guide is a much more comprehensive series of tests
https://www.dropbox.com/s/b1x1ojthv4h7925/Troubleshooting%203P%20PMG%20%26%20RR.pdf?dl=0
But I agree with Cam, if you aren't seeing battery volts rise with the engine being revved, the reg/rect is faulty because you've checked AC output from the alternator is good.

As Paul says, the Electrex RR51 will work as a replacement if you still want to have a charge warning light.
https://www.electrexworld.co.uk/cgi-bin/sh000001.pl?WD=rr51&PN=RR51%2ehtml#SID=439
The alternative (which is cheaper until you add p+p) is the Ignitech R82 (not on the website but listed in their price list).  If you need 2, then it becomes the sensible and cheaper option (only 1 lot of P+P charges)


 
Rob = Bradders
I told you he would pop up, very good with wires and the black art of see no evil, hear no evil, smell no evil, but don't bloody touch it! especially if its 415V
CLEM
 
Rob said:
The type of regulator/rectifier fitted is a single phase device.  This Electrex video explains how to test a three phase reg/rect ... but the principles are the same. 
This Electrex guide is a much more comprehensive series of tests
https://www.dropbox.com/s/b1x1ojthv4h7925/Troubleshooting%203P%20PMG%20%26%20RR.pdf?dl=0
But I agree with Cam, if you aren't seeing battery volts rise with the engine being revved, the reg/rect is faulty because you've checked AC output from the alternator is good.

As Paul says, the Electrex RR51 will work as a replacement if you still want to have a charge warning light.
https://www.electrexworld.co.uk/cgi-bin/sh000001.pl?WD=rr51&PN=RR51%2ehtml#SID=439
The alternative (which is cheaper until you add p+p) is the Ignitech R82 (not on the website but listed in their price list).  If you need 2, then it becomes the sensible and cheaper option (only 1 lot of P+P charges)
Click to expand...

Hi Rob!

thank you very much!! You are always a big help with this black art! I will check the video.

Regarding the R82, what is the difference with the RR51? Can I order it on the online shop or writing an email? I only pay one, for my 1000, the second is for that friend.

Miguel
 
I have read this guide like 8 times now (to understand it properly), it is really cool. I will print it and hang it on a wall of my workshop. I even read further on google about the RMS Voltage, very interesting 8)
Miguel
 
michipons said:
Hi Rob!

thank you very much!! You are always a big help with this black art! I will check the video.

Regarding the R82, what is the difference with the RR51? Can I order it on the online shop or writing an email? I only pay one, for my 1000, the second is for that friend.

Miguel
Click to expand...

The RR51 has the charge light wire
J
 
Both the Ignitech R82 and Electrex RR51 have the charging (Gen) light output.

Yes, if you order from Ignitech an email works fine.  They send you an invoice to pay
 
Rob said:
Both the Ignitech R82 and Electrex RR51 have the charging (Gen) light output.

Yes, if you order from Ignitech an email works fine.  They send you an invoice to pay
Click to expand...

If you're lucky - took 5 unanswered emails before I engaged a Czech expat who sent one in Czech and i had an answer that night! I've never quite understood how their communication can be so erratic. But it's very frustrating when you're in the middle of placing an order and just want clarification to get it right first time.

I know I'm not the only one to have had this issue - maybe the 'wholesalers' get ready access, but I feel as though something just drops out for individual buyers (even though I was buying two sets plus other stuff). I was glad when I finally had it all in my hands!
 
"Those original rectifiers are not very reliable."

We differ yet again Paul, and you (I don't think) have much experience of them, with your past and present history of triples not being exactly prolific, and a 500 you have not done many years or miles with as yet.

So I differ, TOG is going around the clock for the third time and has only every had the original one, which lasted about 20 years and a replacement (second hand) one from a wrecked bike, still going after another 20 years, good service from both I would say, I would like a working spare if any one has one to sell. If I had a few (say 5) broken ones I have a mate who is good with this type of problem and might be willing to attempt opening them up and seeing what has failed with a view to unfailing them.
CLEM
 
I beg to disagree Clem.
The reg/rect on Corinne's 500 was fried when we got it and my ex wife's 500 reg/rect died due to a connecting tang breaking.
And Corinne's 500 has probably done around 5000 km now. With an Electrex RR51.

Paul
 
I have to admit Paul your story does seem to be more common than mine, ex wifes bike probably suffered vibration/mounting woes, causing a broken tang, not really an electrical failure, and Corrinnes 500 did have some, err, lets say interesting DPO features, such as stripped bleed nipples, the wiring defects probably caused its demise, so poor mechanical ability evident (I still wish I had bought it for myself)  just saying its not always the case.
CLEM
 
CLEMTOG said:
I have to admit Paul your story does seem to be more common than mine, ex wifes bike probably suffered vibration/mounting woes, causing a broken tang, not really an electrical failure, and Corrinnes 500 did have some, err, lets say interesting DPO features, such as stripped bleed nipples, the wiring defects probably caused its demise, so poor mechanical ability evident (I still wish I had bought it for myself)  just saying its not always the case.
CLEM
Click to expand...

I hope to have time to look at it this winter. Cam chain will be changed, left inlet valve clearances need doing and I have doubts about the head gasket. It's pissing oil but I'm not sure where from.

Paul
 
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