flat batt

[fuel]

just been out for a stonking great ride on my 98 cbr600 fw, got home, turned bike off to open gate, got back on, wont start

seems batt gone flat, but dont know why

any ideas

also, can i use a car batt charger to charge my bike batt

please help

thanks guys and gals

[DanceLikeAMon...]

This is something I am looking at on my GS500 (my battery went flat mysteriously as well), and from what I have read on this site it sounds like your regulator/rectifier isn't working properly.

You can check it by starting the bike, and then revving it at 5000 revs, stick a multimeter onto the battery, and the voltage should be coming back as between 13.5v and 14.5v (basically meaning the battery is being charged). Anything less and there's your problem.

Someone with more knowledge will be along shortly with more info I'm sure, but that might help for now.

[Bezzer]

Sounds like the usual Honda reg/rec problem, just to clarify the above, multimeter(on DC volts) across the battery terminals, start it and it should rise from around 13 volts at idle to just under 15 volts at around 5,000 on a CBR. Much more or less voltage wise and it's putting out the wrong charge, in your case probably won't rise anywhere near 14 volts and it hasn't been charging the battery. If you're getting acceptable readings then it's probably your battery given up the ghost.
Car battery charger will do your bike if it has a low/trickle charge function or is one of those "intelligent" type ones, with others you stand a chance of overcooking the battery.
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