anyone know if battery testers are any good? i hate to be caught out
> with a knackered battery and wonder if there is any good testers
> avalible to show when your battery is getting a bit knackered.
A decent electronic tester ain't cheap - it will cost more than several new batteries.
Older types merely measure the voltage while a heavy current is being drawn. You can do this yourself using an ordinary DVM and the starter motor. Disable the ignition or fuel pump and turn it over. The battery voltage shouldn't drop below 10 volts with a decent charged battery.