Dead Battery

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So I've had a 2008 Bonneville for about two months, and everything's been fine 'till the other day. The bike is kept on a battery tender and has always been charged up. I rode about 40 miles, shut the bike off for about 5 mins. and it started just fine. Another 8 miles or so, off and on again - no problem. 4 miles later, off and on again, started right up. 22 miles later, shut bike off, sat for 30 min. bike wouldn't start. No lights, nuttin' - no tools either, I should have known better. After a ride home with AAA, I hooked the battery tender up, in an hour I had lights, in an hour and a half the bike fired right up. Anyone had something like this happen, or have some idea what needs fixin'?
 
Can you determine the age of the battery? I learned yesterday, from a neighbor, that certain brands of batteries only have a realistic lifespan of just 2 years. She keeps her battery on a tender, and she started it the first time in a while two weeks ago, and then a little later, it wouldn't turn on at all. She was told that 2 years was about average for that brand of battery from Cycle Gear.
 
Can you determine the age of the battery? I learned yesterday, from a neighbor, that certain brands of batteries only have a realistic lifespan of just 2 years. She keeps her battery on a tender, and she started it the first time in a while two weeks ago, and then a little later, it wouldn't turn on at all. She was told that 2 years was about average for that brand of battery from Cycle Gear.
Hi, Greyfell - I don't know the battery's age, it's a sealed unit and hasn't given me trouble in several shorter stop and go rides - I've kept several bikes on tenders for years, and the batteries have lasted much longer - I owned a Sportster for 10 years, kept the battery "tended" and sold it with the original battery. I'd be happy if it is just the battery - I just wondered if anyone had the same problem and had a fix. Thanks for your reply!
 
This really sounds like a dud battery as it is charging to a degree from two different sources. It just sounds like it cannot hold the charge.

Once you have charged it what is the actual voltage.
 
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First up I would be checking the battery is holding the charge, take it off the tender when fully charged and see if it holds charge for a number of days, then I'd be checking the regulator/rectifier, there should be something on you tube for checking this, find the unit and check the wiring, if that is OK you check the current charging the battery is within spec when running the bike. Not sure about modern Triumphs, but rectifier/regulators are a weak point on a lot of modern bikes, they can just fry themselves and the first you know of the problem is a flat battery.
 
Thanks for the input, folks - I'll let the battery sit for a few days and check the charge - probably just buy a new one and ride with a charger and extension cord in the saddlebags 'till I know if it's dependable or not.
 
If the battery does hold it's charge after a few days maybe the short trips with multiple stops could have killed it. If there's not a lot of time to charge it between stops, could have run it down. Just a possibility to consider.
 
If the battery does hold it's charge after a few days maybe the short trips with multiple stops could have killed it. If there's not a lot of time to charge it between stops, could have run it down. Just a possibility to consider.
Hi, Steve - thanks for your reply - I thought of that, but have done very similar rides many times on various bikes, I'm lettin' the battery sit "untended" for a few days to see what happens. Stay tuned for the next exiting episode...
 
I think it may be the reg/rec that is failing. I had the same problems on a 05 T100, and an 07 Scrambler.
I would do the following checks,
start the bike up, let the engine warm up then check the voltage across the battery terminals with a multi-meter. Set the meter to 0 to 20 on the DC scale, you should have a reading of around 12.5v. Then increase the revs to 4000rpm, and the voltage should rise to around 14.5v. If either reading is outside these figures I would check the alternator output.

Follow the wire from the alternator and disconnect it, there are 3 wires in the plug.
Set the multimeter to 0 to 100 on the AC scale, start the bike and hold the revs at 4000rpm and check the voltage between each wire. There are 3 wires so you will take 3 readings, (wire 1 and 2, wire 1 and 3, and wire 2 and 3).
You should have between 60 and 70 volts.
If the alternator readings are good, but the voltage across the battery is low it has to be the reg/rec.
Unfortunately, Triumph have not issued any method of testing the reg/rec other than replacing it with a known good one.
On both occasions I replaced the standard unit with a high power Mosfet unit that is a plug and play direct replacement for the original. Here is a link to the one I used, Triumph Bonneville Black 2004-2009 Regulator Rectifier Hi-power MOSFET - RR155 | eBay

Good luck!
 
I think it may be the reg/rec that is failing. I had the same problems on a 05 T100, and an 07 Scrambler.
I would do the following checks,
start the bike up, let the engine warm up then check the voltage across the battery terminals with a multi-meter. Set the meter to 0 to 20 on the DC scale, you should have a reading of around 12.5v. Then increase the revs to 4000rpm, and the voltage should rise to around 14.5v. If either reading is outside these figures I would check the alternator output.

Follow the wire from the alternator and disconnect it, there are 3 wires in the plug.
Set the multimeter to 0 to 100 on the AC scale, start the bike and hold the revs at 4000rpm and check the voltage between each wire. There are 3 wires so you will take 3 readings, (wire 1 and 2, wire 1 and 3, and wire 2 and 3).
You should have between 60 and 70 volts.
If the alternator readings are good, but the voltage across the battery is low it has to be the reg/rec.
Unfortunately, Triumph have not issued any method of testing the reg/rec other than replacing it with a known good one.
On both occasions I replaced the standard unit with a high power Mosfet unit that is a plug and play direct replacement for the original. Here is a link to the one I used, Triumph Bonneville Black 2004-2009 Regulator Rectifier Hi-power MOSFET - RR155 | eBay

Good luck!
Thanks - I may give that a shot if replacing the battery doesn't work...
 
I haven't found a chart for other areas but here's the life expectancy of a battery in the US based on the area you live in. Each battery company has basically the same chart so I only grabbed the first one I saw.

TiresPlus-Battery-BatteryExpectancyZone.jpg


I haven't found a chart for other areas but here's the life expectancy of a battery in the US based on the area you live in. Each battery company has basically the same chart so I only grabbed the first one I saw.
 
Up here near the cooler north Atlantic our batteries last for many years.
In fact the original battery that came with my Bonnie is now 11 years-old.
Rather than risk it, I replaced the battery just last week. The old one certainly doesn't owe me anything.
I only use Yuasa batteries in all my bikes (including the vintage bikes) and I have no trouble getting 7-8-9 years out of them.

It's a known fact, as hemi has shown, batteries in hotter climates have a much shorter life.
 
I'm planning to change mine shortly, I'm running on borrowed time and don't want to get caught in the middle of nowhere with a dead scooter.
Probably a good move.
Sometimes it's better to spend the money than to end up in a bad situation that could cost much more to get out of.
That's why I bought a new battery for the Bonnie.
 
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