Alternator question

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nortncom

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So here is my situation. I have a mk3 commando that my father built in the 90s; however, he passed away in 2000 when I was 13, so the only way I know what was done to my bike is through a spread that Classic Bike magazine did on it in 1994. I am in the process of swapping out the Boyer ignition for the Trispark and rewiring the whole bike. My main question is about the alternator and the Boyer power box. My alternator/stator has three wires coming out of it, and two are joined together so it could be connected to the single phase boyer power box. Upon doing some research, I found out that the mk3 came with the rm23 from the factory, which is a two wire setup. So, my three wire setup has to be a rm19 or rm24; moreover, the rm19 would be a downgrade from the rm23 I would think, so is it safe to assume the bike was fitted with an rm24?
 
If its a Lucas alternator the stator should have a part number stamped on it, assuming anything on these bikes is fraught with danger. Especially in this case as it you know its not standard any more. Once you have the number google it with Lucas and see what comes up.
 
Also, a Lucas type 3-phase stator has nine laminated core poles. A two or three wire single-phase stator has six.
3-phase:
Alternator question
 
My GUESS is your Dad retrofitted an older type stator. Three wires vs two is of no concern if both versions are 6 pole, as connecting the wires externally is the same as what is done internally with 2 wire stators.

I would not be concerned about the wattage as long as your lights stay bright above 1500 rpm. Having an excess of wattage over and above your needs is simply superfluous.

Slick
 
When I pulled the primary cover to clean the clutch plates, I do remember seeing Lucas on the alternator/stator, so I'm sure they are of Lucas origin. I was hoping to not have to pull the primary cover again because I finally got it to stop leaking when I installed it the last time. What is making me think it is a 3 phase (besides three wires) is the bike has never had headlight/horn issues, even with a 55w 9003 headlight bulb. Assuming it is a 3 phase, it is safe to run it to a single phase 180w Boyer power box? It has been running that way for quite some time without an issue as far as I can tell.
 
Don't do anything until you verify 6 or 9 poles on the stator.
I ran MY MKIII for 4 years in a no headlight state on a single phase 180w. No problem?
One week at Daytona florida ( headlight state) for bike week and I was limping home to the hotel...60W head light OFF.
 
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