I went out for a long run at the weekend, car started on the button and was very well behaved until I got home.
I parked up on the drive, switched off the engine and opened the garage door, went back to the car and couldn't start it. The car would hardly turn over, a volt meter across the battery terminals showed as low as 4v when cranking.

I've tried plugging the battery into an optimate but after the charge cycle it turns on the warning triangle.

Any ideas as to why a 4 month old battery would suddenly stop holding a charge?

[Edited on 9/7/07 by chockymonster]

is it getting to hot ?

not that I've noticed, it's not near the exhaust and the area it's in doesn't get hot.

Chocky,

Had somthing similar with an R1 at SVA,

Is your voltage regulator earthed ?

regards

Agriv8

Earthed in what way?
It's mounted directly onto the ali panel over the driver's feet. As for electrical connections, it's as it was on the bike.

Sounds like it has been getting over charged

Is the alternator working and charging the battery as a initial check? I thought I had killed a bike battery because my alternator stopped charging when on a run. I just made it back but the battery wouldn't hold a charge using my bike battery charger. However at the bike shop their sophistomacated charger was able to bring the battery back from the dead!