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Discussion Starter #1
So I just picked up an '04 with 11k miles. One owner. All stock except pipe and PCV. No damage at all.

Picked it up, rode 10 minutes, stopped at store, fired up fine.

Rode stop and go for 20 more minutes WITH HIGH BEAMS ON, stopped for gas and she wouldn't start. Turned over very slow but just not enough juice to crank.

Jumped it and got home. Put on trickle charger and the battery appeared to charge to "green" with 12.7 or so volts. Battery was replaced about 1 1/2 years ago (owner gave me receipt).

Only testing so far is voltage as follows (after full trickle charge and fully warmed up ):

Idle with high beam OFF: 14.3-14.6 volts
Idle with high beam ON: 13.0-13.4
4,000-5,000 rpm's: 14.3-14.6

I read a few posts about this happening. Plan on removing all fairings and detailing bike. At that time I plan on pulling the regulator and testing, pull all connectors and lube, etc.

Thinking it's the regulator or stator.

Anyway, thoughts?
 

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Check all those connectors. Find, clean, and tighten all the grounds as well.

My bet is the battery is toast, it's birthday has little to do with its effectiveness. Especially true with bike batteries.
 

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if your voltages are what you say they are, then it's probably the battery. did you use a good meter for testing? they're a little bit high, if anything.
 

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Take that battery to a shop (Autozone) for a load test.
If she comes up trump, the RR is at the rear/left. Undo the big white connector and do a resistance (Ohm) test and mease AC current over (each combo) of the yellow wires. di this with the engine (altenator) well warmed up. as the revs increase (to say 5k), so should your Vac.
Post up results here :-0
 

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Discussion Starter #7
if your voltages are what you say they are, then it's probably the battery. did you use a good meter for testing? they're a little bit high, if anything.
Thought that might be issue so used two....
One simple Volt gauge only and one multimeter (Harbor F. special).
Same results.
 

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Discussion Starter #8
Update: Pulled battery and it checked out ok.

Connected my small volt meter to the trickle connection and mounted it on the fairing support bar so I could monitor the volts during riding.

Took it on a 15-20 minute ride.

Cruising in 3500-6000 rpm range it was steady at 14.4-14.5 volts.

Stopped at light it would mostly stay at 14.3-.4

Then suddenly during idle or at low rpm cruise it would drop to 2.6 then come up slowly to 13.5 range then down then back up 14.4-14.6 when I would increase rpms. Seemed like it was acting weird but never saw 15.0+ volts... went to 14.6 max.

For the most part I left High Beams off but when I turned them on at speed it wouldn't affect volts... only when at idle would the V's pull back.

When I returned I let sit for few minutes (like when I got gas) and she started right up.

Next step, Regulator pull and test.

Any thoughts on why volts suddenly acted weird when at a consistent RPM?
 

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Discussion Starter #9 (Edited)
Update. Swapped the regulator and still the same. Reinstalled the original.

Think I have the issue isolated to the turn signals/high beams

After riding a while and stopping a lot to get the temp up, charging was consistently staying in the 14-14.5 range. High beam on pulled the volts back to 13 or so. It's when I use my turn signals that the volts plummet to 12.0-12.5 and act weird.

When i turn off the signals, volts slowly (and I mean slowly) climb back up, then when I rev with them off the volts jump back up to the 14 range.

I did the signal test many times with and without using the high beams and got the same result.

Short somewhere with signal wiring? Switch issue? Normal for volts to drop to 12-12.5 range with signal and high beam use? Thoughts?

Thinking Stator problem possibility as well.

btw, signals are OEM and appear to be functioning normal.
 

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it's more likely to be a wiring issue between the charging system and the battery. if the signals drew enough to pull the whole bike down to 2 volts the fuse would blow.
 

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Discussion Starter #11 (Edited)
it's more likely to be a wiring issue between the charging system and the battery. if the signals drew enough to pull the whole bike down to 2 volts the fuse would blow.
Yes. Did another test this afternoon. After 15-20 minutes again in stop and go traffic I didn't use the signals or high beams once and after the bike got hot it pulled from the 14.0-14.5 volts to 12.2-12.5 when stopped at idle. Then at idle while waiting in the bank teller line i watched it go from 12.2 to 14.5 slowly then it plunged almost instantaneously to 12.2-12.0 again. Seems like when the bike gets hot the volts start to get very erratic at idle. Maybe sudden drop is due to rad fans kicking on?
 

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Discussion Starter #13
fans will certainly pull the voltage down. have you watched the temp gauge and found a correlation?
Yes, there is a correlation. I went ahead and did this "Ricks Motorsport Electrics" Stator test it seems pass fine.

I think I am going to pause a bit here, relax, and just use the bike and monitor the volts. I won't charge the battery for a while and just let the bike do the work. Maybe I jumped the gun a bit with my OP and hit the panic button too soon. Maybe it didn't have enough juice to start because the bike hadn't been used much before buying, my ride involved a lot of stop and go (fans kicking on), and I had the high beams on the whole ride.

If Autozone says it passed the load test, could the battery still be a dud... a weak duckling for this big V-Twin?

Anyway, i'll update you in a bit.
 

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don't ride around with your high beams on for one. there's no need, and you're adding an extra 4-5 amps on your system. unless it's dark on the highway of course.

i suspect you may have got a bit excited. jsut make sure all the connections are good, and if you want, charge the battery with a charger. the systems on these bikes aren't for bringing a low battery back up, they're for maintaining the charge over time.
 
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