I have a 2001 GS500 and my bike is having trouble. I have bought 2 new batteries and still having the same problem. The bike starts fine for about a week or so and then the battery goes dead and I have to charge it. I have also started the bike and it has run fine than I get somewhere and come back 30 mins later and the battery is dead but the ignition, oil and headlight are on but the bike won't start so I end up push starting it. I am also having trouble cruising it seems like it takes it a second to get going. I switch gears and it has hardly any power and then it takes off to the speed it should have any ideas.
sounds like you have some kind of charging issue
You can find a charging sytem troubleshooting guide on Kerry's website. I suggest you work your way through it:
http://www.bbburma.net/Documents/JohnBates_ChargingCircuitTests3.pdf
Are you charging the new battery before you drop it in the bike?
My ol' pappy used to say that new batteries come with only about half a charge, and should be charged to full before being put to use... but good ol' pappy used to love the drink :cookoo: so he could be wrong.
Your generator isn't charging the battery, I had the same problem twice, on a Yamaha FZR600 and a FZR1000 (which is why I don't ever buy Yamahas any more). Run the tests on the charging system, but I bet that's what you will find the problem is. Hunt for a rewound unit to replace it, new ones are outrageously priced.
are you running any non-stock wiring? you could have something pulling juice from the battery if it wasn't installed correctly. I had this same problem with a battery. the PO had put on a bunch of running lights and they were draining the battery. I stripped em off and went back to stock wiring. no more problem.
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