I have a 1991 Mazda Miata MX5 as a second car.
My commute is 53 miles, but it can take about 2 hours in the morning, although it is 55 minutes in the evening.
The battery is less than 6 months old. Given that this is a second car, how often do I have to make the commute to keep the battery charged through driving alone?
If you need any more info, please ask.
[Update] The car is parked on the street when not in use.
Btw, please note that I do not own a charger and am asking about keeping the battery charged through driving alone
[Upperdate] Some nice answers there, all amounting to the length of a piece of string. While I realize that it is somewhat subjective, I would be happy with a definitive, albeit qualified, answer once very X weeks
. I currently drive it once per week, but would be happy to do so less frequently.
[Yet another update] There are cheap and simplistic devices, like this one, which can read vattery charge from the cigarette lighter. If I get one, how much charge do I need before knowing that I need to drive to charge it - or shoudl that be a separate question?
[Final update] I bought such a device. I am currently giving the car 2 @ 50 mile trips once every three weeks. She always starts first time, no problem, and the device always read about 13(!) volts. I might stretch to once every four weeks and see how that goes