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#842808 03/14/21 1:28 pm
Joined: Oct 2012
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knuckle head
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knuckle head
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I have a nice looking generator for my A10 project....As usual the commutor is worn down and the field coil is shabby..I had planned for using a 12 volt system and have the battery and Rex Speed shop 12 volt regulator in stock....Looking around I see 12 volt armatures and field coils made in the UK are about the same price as new 6 volt items.
. Has anyone here installed the 12 volt parts and saw an improve in low speed charging as claimed in the ads? I'm more interested in actual experience than opinions, thanks


79 T140D, 89 Honda 650NT ,61 A10 .On a bike you can out run the demons
"I don't know what the world may need
But a V8 engine is a good start for me
Think I'll drive to find a place, to be surly"
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T
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I have rebuilt generators with both proprietary items and my own rewinds.
The cut-in speed is definitely in the same range as the six volt set-up.
However, don't expect to get a great usable wattage output as heating will be the limiting factor.

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R
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#1. The main reason to convert to 12V is that "iffy" connections won't have nearly the same effect on the total system. This is a function of Ohm's Law... which is why all cars converted over from 6V. Remember, it's a Law of electrical systems, not a request or suggestion.

#2. The other "must have", even if you stay 6V, is to get one of the newer fully electronic regulators. I understand you get that with the "12V conversion", but it's always the mechanical regulators that end up giving the most trouble. The generators themselves are extremely simple and reliable.

#3. The biggest single difference between 2021 wiring harnesses and 1960 wiring harnesses is the addition of ground wiring. Absolutely DO NOT depend upon the frame to carry electrical power. Frames carry engines; copper wires carry electricity. So new return wires not shown on the original harness diagram need to connect the battery, regulator, generator, head lamp, tail lamp and accessories. That alone will eliminate 50 electrical issues !

Hope this helps.


Don't hide 'em, Ride 'em !!

RF Whatley
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Make sure you use a regulator with a current limit.
If you don't as Trev says, the dynamo can cook itself.
The ones i make normally set at around 8-9 amps for a
12v setup. The heating effect is mostly current based
so if supplying much more current than the dynamo was
designed for you will generate more heat.
The 12v converted unit regulated at the standard 14.4v
will give around 100w at normal speeds rising to a limited
120w max. Any more and you risk throwing the solder off
the armature. These figures are for a unit at around 25 degC
with good magnets and windings.

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knuckle head
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knuckle head
Joined: Oct 2012
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My change to 12 volts is for the wide and inexpensive availability of 12 volt bulbs....The Rex regulator has current limiting , that's why I bought it..Automotve regulators have both current and voltage limiters.I always make my own wire harness with dedicated grounds and heaver gauge wiring...Other than this, I have no experience with this stuff..
Considering the bike has a magneto , 35 watt H4 headlight and less than 1 amp tail light, the amperage with a charged battery should be the same as the original 6 volt system... Well, I shall go to where no man has gone before with 14.5 volts and 8 amps of armature frying power.....
I appreciate the comments, thanks
Nick, this is the regulator
https://www.rexs-speedshop.com/product/negative-earth-6-12v-solid-state-dynamo-regulator-100w/


79 T140D, 89 Honda 650NT ,61 A10 .On a bike you can out run the demons
"I don't know what the world may need
But a V8 engine is a good start for me
Think I'll drive to find a place, to be surly"
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Mind you don't go blinding anyone with all that light power.............................

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knuckle head
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knuckle head
Joined: Oct 2012
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lol, maybe I'll use one of those super white annoying LED bulbs..


79 T140D, 89 Honda 650NT ,61 A10 .On a bike you can out run the demons
"I don't know what the world may need
But a V8 engine is a good start for me
Think I'll drive to find a place, to be surly"

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