RMxx Lucas Alternator wattages over the years

jimbo

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Does anyone have a chart of what the Lucas RM series alternator, stators and rotors put out over the years?
 
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Can we ask with what purpose in mind ? - reduce the need for long rambling answers that may not address the issue.
 

jimbo

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Well, I have a Scott with a 6v Miller alternator , its ready to give up the smoke, Millers are not available the Lucas's are drop ins. However the drive is wonky, like the Brits would say so I need to find a new old stock early Lucas 6v ,3 wire ,stator and rotor that has the least amount of drag ( lowest power).The alternator has to be three wire to be wired without an regulator, which is to say switch regulated.
 

jimbo

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Is there someone here that knows the output difference between a RM15 and a RM19?
 
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jimbo said:
Is there someone here that knows the output difference between a RM15 and a RM19?

A Osborne said:
British motorcycles prior to the mid 1960s would all be wired with 6V alternators; the earliest Lucas alternator would be the RM15 or RM18. These only gave of the order of 80W, so they were surpassed by the RM19 which, assuming that all was working correctly, gave 110W. The rotors and stators are not interchangeable between the two types, even if at first glance they might seem to be. The RM15/18 has a 70mm rotor diameter while the RM19 and RM21 and in fact all subsequent rotors are 74mm.
From: http://www.nortonownersclub.org/support/technical-support-electrical/6v-to-12v-alternator-conversion
 
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I don't suppose it would be a difficult rewinding job.

Are the coils shorting to earth at the moment?
 
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