01-01-2020, 09:52 PM
Paul, my guess is you have a magneto engine? If so, the M position has the dynamo switched off, with only the mag working. The dynamo only operates when switched to D. On the face of it that charging rate should see you through the night, but I’d worry that the dynamo is working too hard. I’d turn the charge rate down to about 6 amps, and take a spare battery if you have one. You can always not use it, but if you need to.......
Alan Fairless