Battery discharges at high revs

[adreid]

Just recently as the temp outside has got bad I have had problems with the battery/ charging system. I went out with a friend couple of weeks ago and we were giving it some welly then all of a sudden I lost all power and the bike stopped. We swapped batteries and it started fine. I returned the bike home and tested the output voltage from the charging system as described in the H model manual. The output was 14V at 4000rpm as expected so I thought everything was fine and I had had a poor connection. The battery charged up fine with a trickle charger.

so I took her out again last night to give her a run. All started well, went to local supermarket taking it steady. When I got back on the bike I gave it a bit of a thrashfor 10 mins then wen't for some fuel. When I went to start the bike again it was dead.

I can't understand it because it seems to be the high revs that kills the bike, though I can't be certain. I'm gonna test the output from the alternator through out the full rev range when weather is better. I am also gonna test the resistances of the regulater rectifier as the h model manual describes. Has anyone got any idea's, i've looked through the forums but no similar problems seem to have come up.

[Ballsout Racing]

At high revs tells me that your battery is weak, a battery can still charge up if it's faulty but may not hold the charge. Did you try a thrashing session with your mates battery?

[adreid]

Not yet as he needs it for his bike comuting, I'll give it a try.