Thread: battery power
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Old 30-Mar-2009, 22:25
twpd twpd is offline
Deceased 02/10/2010 - R.I.P.
Ducati Corse
 
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Quote:
Originally Posted by Glyn
after a good charge the battery holds a good 12.6 volts when running it shows 14.5 volts.
i think this means that the rectifier and battery is good?
have cleaned all my connectors down that way an all. so why does it still turn over slower than a slow thing. always starts but its a struggle

An easy way to check your charging system is working properly is to observe a rise in potential across the battery terminals when you rev the motor. At idle it should be around 12.5-13 volts. Rev the motor to about 3-4000 rpm and you should see it rise to about 14-14.5volts and hold steady from there (as yours seems to be doing).

The battery might still not be very good insofar as it's capacity might be reduced or it's not holding charge - there isn't really an easy way to determine this other than by seeing if it runs down overnight or a period of a few days when the bike is left standing or by doing a rundown test using a test load.

If yours is struggling to turn the motor over then that tells me that really it is lacking in capacity and the ability to deliver a high current when demand is placed upon it. This is possibly because of a build-up of sulphate on the plates - there's no cure for that other than a new good quality battery.

Sometimes batteries can recover by cycle charging them.
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