For now you will be good running on 12 volt. Just keep in mind if it ever does give trouble your spinning the starter twice as fast as it was designed for. Again, if it ever does give trouble you will want to upgrade your coils to a heavy duty/hi torque coil and a heavy duty 5 roller drive instead of the original style 3 roller. The new heavier coils will really make a starting difference without worrying about them being able to handle the 12 volt, lots more copper in them than originals.
Thanks
Ken
www.classicgenerator.com
