I have not stumped for a charger, as you can use a normal charger as long as it does not have one of the 'de-sulphate' (?) modes. And the post 81 BMW R100 regulator is up to the job.
Just remember, when you start it up, go for a ride. And switch off them heated grips/vest/seat a few minutes before the end of the ride, so the poor battery has some juice left in it when it comes round to starting her up again. They have a tendency to 'give their all'.
Ballistic actually recommend a 16 cell battery for airheads. This battery was apparently developed for Harleys. It is double the price of a 12 cell battery....Made me think twice. 12 cell should be fine for a stripped down 82 R100 with no extra's.
Cheers
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