I'm in the process of trying to rebuild a M116 Alpina basket case. Among the missing & broken parts is the resistor (or as my parts manual says, Ressitor Assembly 85.21-217). Does anyone know of a source for this part? OR, does anyone    know the specs of the original part so I can look for a universal replacement? Thanks.

Try Bultaco Classics (Hughs Bultaco) in Crareyville NY.

Already sent an e mail. Thanks.

I would not worry about replacing that part.  It is only used as part of the lighting circuit.  I would replace all the lights with LED bulbs and make it a closed circuit running off a small 12V battery (should fit in the headlight bowl).  The original lights are 6V and frankly rubbish. 

Replacing with LED would make the machine a lot safer as it would be easier seen.I do have one somewhere that I removed from a bike so I will see if i can measure it up for you later.

 

Thanks for the response.