R 26 electrical problem

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PINCK ANDRE

R 26 electrical problem

Post by PINCK ANDRE »

R 26 ELECTRICAL PROBLEM



I have a problem with a R 26 manufactured in 1958.


These parts are new :

Battery, capacitor, ignition coil ,capacitor, centrifugal regulator, ignition cable, breaker plate, spark plug.

With a charged battery, the motor runs perfectly. After 2 or 3 hours, it stops and it is impossible to restart.
The battery is empty.

I never have more than 6,9 V on the battery when the motor is running.

MEASUREMENTS

I measured the current just before the + side of the battery and there are the results :
Full lighting

slow speed 6,95 A The battery is discharging

medium speed 0,5 to 1 A The battery is discharging

high speed ~ 0 A The battery is discharging

I have the wiring diagram and an electronic voltmeter.

The voltage regulator was manufactured by BOSCH.

How is it possible to make the difference between a defect voltage regulator or a defect dynamo ?

Thanks in advance for your help and suggestions.

André Pinck
Andreas Belau

Re: R 26 electrical problem

Post by Andreas Belau »

Is the BOSCH voltage regulator as it was originally, or has it been changed to an outside-one?
I have a R26 too and I changed the regulator to an outside-one and had no more problems since then.
What else did you do?
I bought my bike 22 years ago, took it completely to pieces an rebuilded it from the beginning.....
And it is still running very good.
rolf

Re: R 26 electrical problem

Post by rolf »

hallo,
your dynamo is charging, but not enough( because you a difference of discharging under different revs).it could be different things.
1. check the dynamo, you have to measure the dynamo by checking the current between D+(61) and DF( or between the 2 charcoals(?)these black square things with a wire).
Attention: if the complete dynamo is ok., your current runs over 15 Volts(that is why you need a regulator).
if it does not, cheque the "Feldspulen"(these 4 round wiring in side the dynamo), when you put 6 V on DF and D+, they shall become magnetic(strong)
if it is all ok, it is your regulator( I think you have the original F-Regler), you can check it and repair it, but my english is too bad to explain it.
rolf
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