Bonneville America Forums Forums Technical Forums General Tech Light Bar / Battery Question

Not sure if this is exactly the right section for this question, but here goes:

I recently had a light bar installed on my '07 America (Triumph model). During the installation, the mechanic said that there was a short in the original wiring harness, and it had fried the wires so they had to rewire it all. I wasn't psyched about it, but I'd bought the light bar used, so I figured thats a risk had to accept.

Anyways, fast forward about a week, I started having issues with the battery draining. Twice in one week, I had to get my bike jumped because I had no juice. I took it back to the mechanic (also a Triumph dealer) and they replaced the battery for me for free because it's still under warranty.

Everything was fine for about a month, and then I just had the same problem this weekend, with my battery being drained after a short ride and needing a jump.

My question is this:

If I am using the bike for primarily short trips in the city, should I expect this sort of behavior with the driving lights on all the time? Do other folks normally shut them off on short trips because the RPMs aren't high enough to produce enough juice for the alternator? Is there anything I can do to remedy this issue (install a better alternator)?

Any recommendations / advice / personal experience would be greatly appreciated.

I bought the driving lights primarily to help me be seen by other drivers, and I'd prefer to be able to keep them on at all times without a hassle.

-Brett

You should have enough power to handle the two 35 watt bulbs on the Triumph light bar. The best bet is to put a voltmeter across the battery, the voltage should be 12.6 volts, then start the bike. Note what the voltage is at around 2500 rpms. Should be between 13.5 to 14.6 volts with normal lights on. Turn on the extra lights and note the voltage. Should still be similar.

I run the light bars all the time on both mine and Karens bikes....no issues.

I leave my light bar on all the time too. I would suspect the battery if you didn't say it was replaced. Sounds like there may still be a short, but I would think it would drain your battery immediately. I would suggest doing the voltage regulator mod.

http://www.bonnevilleamerica.com/forums/...true#Post359794

Well, I live in San Francisco, and the place is only 7 miles across in any direction.

So, a lot of times I'm only riding a few miles. On the weekends I get out for longer rides, but weekday trips within the city are normally less than 20 minutes each way.

Thanks to everyone who has chimed in with advice. I am going to pick up a cheap voltmeter and take a look myself. Electrical systems aren't my strong point though, so if anyone has a little more insight into what exactly I should be looking for from my voltmeter readings, I'd be much obliged.

-B

I have a factory light bar on my bike, I use to shut the lights off when I was about 5 min. away from home (so the battery can recharge) but every body here said that the charging system can handle it, so I left them on. I have a 04' with the original battery!(knock wood) Something must be causing a slow drain on your battery.

Hey Brett... I'm thinking run a voltage test across the battery terminals with the bike running at about 2000 RPM. Run the test with and without the lights on. Either way you should get about 14 volts across the terminals. If there is a huge difference in your readings ya may have a problem with the charging system.

Sounds like you have a very small discharge probably all the time. If you have access to finely calibrated ampmeter disconnect pos terminal and connect ampmeter in series to it. If discharge is present should show it. Disconnect wiring loom in stages to isolate short-ie. when meter goes back to o will be in the wiring that you have just disconnected. This is with the bike at rest and no lights switched on. Have used this many times to isolate this type of problem. Hope this helps-the ammount of discharge can be just a trickle even milliamps but will drag your battery down. Obviously the longer it sits the worse it gets. Voltage can be misleading as the charging amps can still be under the spec as I discovered as a apprentice many decades ago.

Thank you to everyone who has chimed in, I feel like Im moving in the right direction now.

I guess my only question now is can anyone recommend me a decent / not too expensive voltmeter ( ampmeter? )to use for testing?

Electrical systems has always been one of my weak points, but no time like the present to remedy that.

-B

Look for something called a multi-meter which can do the volt thing, amp thing, resistance thing and so on. Ya don't have to spend much on one these days and they are pretty much available at any store that sells hardware, auto parts, building supplies. Try Walmart for a cheap one.

or get one at Target

Erwin and Kent1969 could both be right. Short in traffic rides will not recharge the battery adequately. But, if there is a systematic problem it's best to fix in the long run. If the problem is your riding habits then a BatteryTender should be in your future. I can't imagine owning a bike without one,. I own three, well till one got wet last week. I went to Engles yesterday and they were out of BatteryTenders, but they had the Triumph "tender" in stock for $58, nice thing is that they have a battery check option. Good luck.

Batteries Plus also carries Battery Tenders.