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KimT110, kommando
Total Likes: 3
Original Post (Thread Starter)
#852288 06/24/2021 5:52 AM
by KimT110
Hi Forum,

i am getting confused about the electrics on a T6 1965 the I am looking to buy, and hope that some of you can enlighten me:-)

The bike has been "converted into a bonneville look alike. i.e the Nacell has been removed and a smaller US tank mounted.
Seller says it is a 6 volt bike, and here I get confused.

As far as I know the 6T in 65 had a 12 v system with a Zener under the seat.
In this case I expect the Zener would be used to regulate the voltage?

Now the Zener has been removed and I do not see any other means of voltage / charging control, and there is one 6 v battery mounted.

I believe that the 65 Bonnevilles had a 6 v system.

Looking in the spares catalog it looks like both the 12 v and 6 v systems of the year uses a RM19 stator.


can it really be the same stator in both systems?
how is the charging / voltage regulated in the two systems?
also it seems that at least the 6 v system currently on the bike can run with a disconnected battery?
What is the benefits of the seller having converted the system to 6V?
I do have Photos of the schematics , but I am not able to attach photos into this message.

Anyone who can help me understand these differences?

Liked Replies
#852295 Jun 24th a 08:05 AM
by gavin eisler
gavin eisler
The 12 V set up uses a Zener Diode, much simpler wiring
The 6 V set up switches the alternator coils, and the switch has an Emergency setting for starting with a flat battery, this has a lot more wiring to the switch. it does not really regulate, just changes output to max with the lights on, its not great and will boil a battery if a lamp bulb fails since the lamps loads are needed to balance the demand/ output.
2 members like this
#852324 Jun 24th a 02:15 PM
by gavin eisler
gavin eisler
if you go to 12 V, and wish to run with Electronic ignition the 6Volt coils can remain, EI works better on twins with two 6 volt coils.
1 member likes this
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