Running Issue - electrical issue

[RiderMike]

I’m interested in buying a 2005 ST1300 a gent is selling. Unfortunately, the bike won’t hold a charge. It starts right up with an external charging source, but once it’s removed the bike dies. I’ve been told this is probably a voltage regulator/stator issue. The owner thinks it’s just a dead battery and wants to sell the bike as is. I’d like to know what any of you folks know or think about this. Externally, the bike is in great shape, but I’m more than slightly hesitant to buy something that will cost a lot of money to fix.
Mike

 

[Willsmotorcycle]

Mileage? Any obscene 300 watt lights or such added?

 

[Sadlsor]

It's easy enough -- or at least CHEAP enough, like FREE -- to have the battery load-tested at any auto repair shop.
If said repair shop doesn't / can't do it, I wouldn't be taking any of my machines to them...
Further, if said seller were actually motivated, he would have it tested for free, and thus avoid buying a new battery for it.
Further and further, he should buy a new battery, install it, and recoup his battery outlay in the sales price.
Otherwise, take him an itemized estimate for voltage regulator repair / replacement from a Honda motorcycle shop, and talk him down by at least that much.
So many ways to go with this... but how many miles on the ST?

 

[SMSW]

Troubleshooting a bike that is not yours is a bit of a problem. I'd think there are two ways to approach this. One would be to negotiate the price to something that is comfortable to you to assume an unknown but limited risk. The other would be to try to fix it. I'd take a car battery, disconnect the bike's battery, and use jumper cables to connect the car battery to the bike's wires. Start it up and use a voltmeter across the battery. At fast idle you should get 13+ volts. If you don't get this, chances are something is wrong with the charging system. A slightly different way to deal with this is to buy a cheap battery (any bike you buy might need one) and pop it in. Test again w. the voltmeter.

Or do what Mark suggested - oops, @Sadlsor.

 

[Sadlsor]

Troubleshooting a bike that is not yours is a bit of a problem.

Exactly. Add to that, all the questions we all have... as mentioned, there are so many ways to go. There's so much we don't know here.
But initial prospectus indicates a high likelihood of negotiating a price more to the favorable side of @RiderMike .
It can be fun, shopping for bikes, and more fun when dealing with private sellers.
"There's BUG guts on this fork tube! You need to sell it for $100 cheaper now."

 

[RiderMike]

It's easy enough -- or at least CHEAP enough, like FREE -- to have the battery load-tested at any auto repair shop.
If said repair shop doesn't / can't do it, I wouldn't be taking any of my machines to them...
Further, if said seller were actually motivated, he would have it tested for free, and thus avoid buying a new battery for it.
Further and further, he should buy a new battery, install it, and recoup his battery outlay in the sales price.
Otherwise, take him an itemized estimate for voltage regulator repair / replacement from a Honda motorcycle shop, and talk him down by at least that much.
So many ways to go with this... but how many miles on the ST?

The bike has just over 35,000 miles on it. He used an external charger to start the bike and once he removed it, it shutdown and could not be restarted with out an external charge.

 

[Andrew Shadow]

You can't check the charging system while a charger is powering it. Disconnect the current battery. Hook it up to another known good battery with booster cables. Start it, rev it up and put a voltmeter on the battery posts and see what you get. This will give you an indication of whether or not it is charging.

You can do this with your car battery, just make sure that the car engine is off so that you are not reading the car's alternator voltage instead of the motorcycle's.

 

[Sadlsor]

The bike has just over 35,000 miles on it. He used an external charger to start the bike and once he removed it, it shutdown and could not be restarted with out an external charge.

I see the sales price going lower and lower... just for the uncertainty.
But 35K leaves you many years, and many tens of thousands of happy miles once this is sorted out...

 

[RiderMike]

You can't check the charging system while a charger is powering it. Disconnect the current battery. Hook it up to another known good battery with booster cables. Start it, rev it up and put a voltmeter on the battery posts and see what you get. This will give you an indication of whether or not it is charging.

You can do this with your car battery, just make sure that the car engine is off so that you are not reading the car's alternator voltage instead of the motorcycle's.

Thanks