Replacement Alternator for N15CS

Hi there I am helping restore a friends 1965 N15CS, we have a new loom from British Wiring which has the 3 wires designed to connect to a RM15 Alternator, is it feasible to use a 10.5 amp RM24 3 wire Stator/ Rotor setup [connected via Lucas 88SA switch], the reason is that as this machine has a magneto ignition and its use will be club runs etc our thoughts are that the 3 wire setup would be easier on the charging system, I am asking this as even though I know the basics electrics are not my area of expertise.

The 3 wire system is easier on the regulator / rectifier when the 3 wire stator is paired with a proper lighting switch.

In essence, the lighting switch selects 1/3, 2/3, or full (3/3) stator output, and matches (sort of)

the stator output to the load. One of the stator leads is common ( from memory, the GW wire), the other two wires are connected to 2 of the six stator coils, the other to four of the six coils. Thus, connecting one of the wires to common gives 1/3 output, the other to common gives 2/3 output, and connecting both to common gives full output.

Slick

Cheers Slick, I understand that, but will a RM24 3 phase connected the same way do the same job?

The simple answer is .......... I dunno, but I doubt it.

Sorry.

Slick

possm said:

but will a RM24 3 phase connected the same way do the same job?

Click to expand...

The RM15 is a three-wire, single-phase alternator (stator). The 3-phase RM24 needs all three outputs connected to a 3-phase rectifier (or 3-phase reg/rec) so it won't do the same job.

Why not fit an RM19 which is 3-wire, single phase?

L.A.B. said:

Why not fit an RM19 which is 3-wire, single phase?

LU47204 Alternator Stator GENUINE LUCAS RM19 6V - Triumph, BSA, Norton Royal Enfield - BBB

6V 3 Wire Lucas Alternator Stator

www.britishbikebits.com

Click to expand...

That is exactly what I did after I fitted LED lighting. Then I used the single pair coils for pilot or daytime running light, and the dual pair coils for main. No need for full output (dual plus single) as the load is easily handled by 2/3 output of the RM19.

Slick

Thanks everybody for their input, as there is no RM19 Stators available in New Zealand and current freight prices due to covid19 my freind and owner of the N15CS has decided to go with plan B, a RM21 stator and rotor and as we haven't got the facilities to test the Zener and rectifier properly we are going to use a podtronics which I have already previously used on my '66 Atlas and '67 650SS, it would have been nice to use the O.E. System especially as night time riding will be a rarity.