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post #1 of 10 (permalink) Old 10-24-2009, 10:06 AM Thread Starter
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Battery dead - Battery Tender flashing red

The battery on my 06 Bonneville seems to have died. The bike started fine one day, but the next day not at all. I hooked the battery up to a Batter Tender and the Tender displays a flashing red light. According to the Tender manual:

"a red light flashing indicates that the battery charger has AC power available and that the microprocessor is functioning properly. If the red light continues to flash, then either the battery voltage is too low (less than 3 volts) or the output alligator clips or accessory ring terminals are not connected correctly."

The Tender seems to be connected correctly to the battery. Any ideas for what I should do next?
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post #2 of 10 (permalink) Old 10-24-2009, 10:15 AM
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Check the battery voltage with a VOM and see what it is. You could remove the battery and take it to a shop for testing. They will probably need to charge it for an hour or so prior to load testing it.
Don't be surprised if it is faulty and needs to be replaced.
If it checks out okay, have the charging system tested and repaired if faulty.
Let us know how things turn out.
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post #3 of 10 (permalink) Old 10-24-2009, 10:55 PM
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Get a new battery.
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post #4 of 10 (permalink) Old 10-25-2009, 01:16 AM
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Happened across this thread that suggests voltage and stability are not what they could be on many bikes including Triumphs due to guage of wire being to small (and wire too long) in a critical part of the charging system.

Those that have been following the "Interesting Battery Problem" thread (high voltage cutoff for starting efi bikes problem) may find the following interesting.


I have owned a few bikes in the past and ALL - VTX, VFR, FJR, KTM have had what I consider a weak charging system...
The Triumphs are no different.

A short personal history: I spent 15 years of my life designing and building high amperage electrical systems for automotive applications. I learned that in order for a charging system to work & charge properly you not only need a good voltage generator & storage source - the connecting system has to be solid, clean and generally over sized...


I bought an 04 Daytona last weekend...upon arriving home, I gave the bike a good going over.
Fluids, air pressure, battery etc...
One of my checks is to alway test the charging I took the seat off (HEY, that's where the owners manual is...) and broke out the trusty fluke meter.
Tested tha battery, and it read fine (12.6ish)
Fired up the bike and voltage is riding in the 13.3-.5ish area...Humph...low...
I grabbed the output wires of the regulator to test the voltage there and WHOA - they're fairly toasty...that's not good (hot wires are a dead on sign of either a bad ground or undersized wires.)

Upon further investigation, I found the same thing I found in the other bikes -the output wires from the regulator were ok size but once plugged into the actual bike wiring, it shrunk ALOT and ran the long way to the battery...

So here's the scoop (or the bad)
Triumph and other bike manufacturers down size the wiring in the bike to save on cost, size, weight or what ever thinking it should be OK but, In the real world, it isn't...
Not only is the wire gauge to small, but, although the regulator is 10 inches from the battery, the actual wires that charge the actual battery leave the regulator and go into the main harness that runs forward on the bike and aventually hooks to the starter where the main starter wire is connected and ran back to the battery.
SO - instead of a 10 inch run of proper gauge wire, they use a wire that is to small and way to long especially for its size and purpose (charging the battery).

The Good:
It's and easy fix...I had it done in under 5 minutes (I did have everything on hand)

Proceed with the following modification at your own risk

All you have to do is get a couple of piese of 12 gauge wire about 10 inches long - one black, one red (if you can use what ever color you want), some ring terminal connectors and a fuse holder

on the bike side of the regulator plug (a white plug), you will see (on an 04 Daytona at least) 4 wires - 2 brown, 2 black.
The brown wires are the voltage output
The black is the ground.

*right behind the plug (on the bike side of the wiring, not the regulator side), cut back the insulation on all 4 wires...clear your self about 1/2" area so you just have bare wire.
*take a small flat screw driver, and open up an eye in each wire (so you have a hole right through middle of the wire...this is a "button hook" connection)
*take the red wire, strip back about an inch of it and then insert it through one brown wire, then the other...then wrap it around both wires and sinch everything up tight (yes, you are connecting/wrapping the wires together). *keep tightly wrapping the wire around until it's all wrapped into one tight connection....if you chose a solder connection, go right ahead.
Now wrap the connection tight with a good dose of electrical tape.

*Now do the same with the larger black wire and the black wires in the plug.

*connect your fuse holder with fuse to the red wire and connect to the + positive terminal as you hook up the battery. (if you get a wired fuse holder with enough wire, you can directly connect the fuse holder to the reg wires and than to the batt - they are availble at car stereo shops)

*install your ring connector to the black wire and hook it up to the - (negative terminal) batt terminal as you connect the battery.

After doing this mod, I fired the bike up and there it is...14.6 +/- volts as it should be...a nice healthy charging system...wires stay cool, lights don't dim, bike runs better (better voltage) and more responsive....

But I can say the every bike this has been done to has shown a dramatic improvement.

This mod is safe, easy and cheap.
The only reason OEM doesn't do this is expense and it would complicate assembly.

Good luck.


This Electrical Charging upgrade thread and follow up post replys can be found at:
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post #5 of 10 (permalink) Old 10-25-2009, 01:30 PM Thread Starter
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Thanks, guys. I got a new battery and have it on the charger now. I wWill let you know if that fixes the problem.
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post #6 of 10 (permalink) Old 10-25-2009, 03:21 PM Thread Starter
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BTW - anybody know how long I should charge a new battery before using? The directions were missing from the battery box.
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post #7 of 10 (permalink) Old 10-25-2009, 03:43 PM
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Originally Posted by BerkBon View Post
BTW - anybody know how long I should charge a new battery before using? The directions were missing from the battery box.
Depends on wether it was bought dry-charged and the electrolyte was put in by the seller or it was already filled before purchase.

A dry-charged battery is stored on the dealer's shelf without electrolyte in it. The dealer must put electrolyte in the battery and briefly charge it before installation in the vehicle. Half an hour should do it.

A wet-charged battery is stored on the shelf with electrolyte already in it. It may require charging before installation. They lose something like 3% of charge per month. There should be a manufacturing date code on it and this will tell you how long it has been stored. We will assume that the dealer has not charged it while on his shelves. Overnight charging is recommended.

Wet-charged batteries that are stored too long without periodic charging may become permanently damaged.
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post #8 of 10 (permalink) Old 10-25-2009, 05:11 PM Thread Starter
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Main Motorcycle: 06 Bonneville Black
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New battery fixed the problem! Thanks for the help.
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post #9 of 10 (permalink) Old 10-30-2009, 12:13 PM
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The stock battery on my bonnie died within a few months of picking it up. I think they probably aren't great batteries and they don't get well taken care of in transit, I'm sure.
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post #10 of 10 (permalink) Old 10-30-2009, 05:33 PM
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My Battery lasted a good year. I now have a DEKA battery in there, It's much better, and it's Local to me(made in Eastern Pennsylvania). it's also an Absorbed Glass Matt Battery, so it's better anyway!

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05 Thruxton TPUSA Exhaust, ARK, Rear Fender delete, Woodcraft Clipons
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