Series D 6 to 12 Volt conversion

timetraveller

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About forty years ago there was a thing called 'the Bell Conversion' which did exactly that. I fitted one and used it for several years. It had two idiosyncrasies. One, you has to rev it hard to get the cut out to cut in, after which it was fine Two, at low revs round some of the country road corners where I live it would not keep up to the demands of the headlight and coil ignition. One evening I was returning from a Club Night with Bill Turner on his open 'D' behind me. Bill had fitted a car alternator to his bike. On the low speed parts I could not even see the light on the road from my bike as it was totally overwhelmed by Bill's headlight. Later, Dick Sherwin and I developed what has become known as the 'Walkernator' and despite the non standard appearance many people are happy with it.
 

Chris.R

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12v Regulator

Hi there interesting topic this, can anyone tell me what make solid state regulator to use.
I am just fitting one of Goffys AO regs which I am hiding on a bracket made today under the battery carrier.
 

Chris.R

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I'm a bit puzzled by the AO regulator, because while most of the companies making electronic regulators make a 12 version for true 12V dynamos (which includes 6V ones which have had special 12V coils or coils and armatures installed) and 6-12 converters which let the output rise to 12V while restricting the field to 6V, the AO appears to be just a regular 12V regulator, which they tell you its OK to use on a 6V dynamo without any mods.

The first generation of 6-12 converters had a lot of trouble burning out field coils because most of them cheated, and ran the field coil at, say, 8V instead of 6V (all voltages given are nominal), in order to get reasonable output at lower rpms. But running a 6V coil on 12V does not seem wise.

Oh, one other thing. While its useful to know that the AO will fit in a Miller box with a little fin bending, those fins are there for a reason - to cool the components inside! Which they cannot do as effectively if the are bend and then enclosed so they are out of any airflow. Once again, I'm not sure how important this is, but is is something to be aware of.
Puzzled one might be I found that no way would the AO reg fit in the miller box so I made up a bracket and installed the AO electronic reg under the battery carrier on the Comet it will run a 12v Lucas E3L that has been built for me from parts with new field and armature so should be OK this in conjunction with standard magneto and LED lighting. the only additional electrical equipment will be a GPS. the Miller 6v has been well overhauled and put in a box as an original part.
Chris
 

mercurycrest

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I was just reading the newly posted "The Series D Comet" and came across this did bit. In short, that's the reason My D, that I bought in 1975, has a Chinamo.... and Koni's (the 2nd Koni on the rear).

"Every machine of course has its faults. Mine has two; the dynamo only lasts for about 15,000 miles, and the rear suspension unit is U/S after one continental tour."
 

bmetcalf

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Did Koni make a special unit for the rear of the D or was it meant for something else?
 

SteveW

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I have used the Podronics regulator w/out any problems. I have also used the original Miller voltage regulator set up w/ surprising reliability. I am a masochist at heart, apparently, and take great pleasure in seeing the little Rube Goldberg device actually work. Good Luck. Also, Doug Wood is a good guy to talk to about this.
 
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