Bad rear left turn signal + draining battery

[JPSmee]

So, I'm back

I've been having an absolute blast with my 750C for the past year (!!!), and I've come to my first major problem since getting her road-worthy. I've noticed that when using my left turn-signal, the light on the indicator is not flashing, but solid. I noted that my rear left signal light appears to turn off, while the front one turns on. No biggie says me, I can always get a new light.

Except, now my bike is draining it's battery, much as it did when I first got her. My knowledge is quite well documented here as being highly novice (), but I was wondering if there was possibly some sort of connection between my dead turn signal, and my draining battery (I'm imagining the circuit being like a set of Christmas tree lights with one burned out bulb breaking the whole circuit . . . )

When I checked the stator last year, all seemed well. I've not torn things down yet, as this only just started, and I thought I'd hit you guys up before I got too far into things.

[TOOLS1]

I doubt the two problems are related. The turn signal sounds like the rear bulb is burned out. As for the battery, you will need to check it, and the charging system.
TOOLS

[LukeM]

Most mechanical flasher systems depend upon a certain amount of resistance to work properly. That's why replacing incandescent bulbs with LED types calls for a different flasher.  I agree with TOOLS: probably a bad bulb or a loose connection to the socket.  Not enough resistance: the flasher won't flash.

Some things to check for the battery issue:
The charging system typically won't supply charging voltage/current until the engine is around 2500-3000 rpm.  There's a graph in the FSM that shows this (at least for the DOHC manual). If everything is working right, you should have about 12.5v at the battery when the bike is not running, maybe 13v or so at idle, and between 14 - 15v at 3000 rpm. Check the 3 yellow wires from your alternator to your reg/rec, and make sure those connections are clean and shiny. Make sure your ground wire to the frame is clean and tight.  Same goes for the reg/rec.

I hope this helps.
Luke M

[sgtslag]

Probably the easiest way to monitor the charging system, is with a battery monitor (or an automotive Voltmeter, but these are not as useful).  This is the unit I have, and I won't be without, again:  link.  It is not cheap, and the battery life monitor, is somewhat questionable, but it will tell you, at a glance, how your charging system, including your battery, are doing.

There are less expensive units, which will plug into a cigarette lighter plug (link; a very useful accessory on a bike, especially if you take 1+ hour rides:  cell phone charger, GPS unit power, voltmeter, etc.).  Almost any type of Voltmeter/battery monitor, will give you a head's up on problems with your charging system.  Cheers!

[JPSmee]

Looks like the battery had just been slowly run down over time (admittedly, I have been dealing with awful traffic lately). I fully charged the battery, then got the bike running. The battery began charging once I hit about 3000 rpm, which is where it is supposed to be.

Now about the blinker. What exactly would I need to do to swap out my blinkers with LEDs (you mention that a different type of flasher is needed)? I imagine they pull less juice, and thus will give me that much more of a buffer for my electrical system.

[shinyribs]

There are some LED turn signals that are direct bolt on,without the need for any modifications. The ones I've seen really dont cost much more than the LED's that require adding your own resistors or changing to another type flasher relay.

[JPSmee]

Well, I'm back . . . I still can't figure this thing out. My volt-meter shows a positive charge at 3000 rpm, yet I can't go for more than an hour without running the battery down to roughly 50% capacity. It's just *not* taking a charge from the charging system. When I took out the battery to set it on the charger again, I happened to notice this disconnected wire (always a good sign, right? ) I've never noticed before:



Any idea what this is? It seems to have the same connector for my turn-signal relay switch, yet there are no available posts for it. As I've never messed with my relay, much less have seen this wire (and I doubt sabotage), I doubt this is the cause.

If not this mystery, any other ideas? I miss being able to ride without worry

[rich]

My 79K has a spare green wire like that too. Maybe they're made to accept a different flasher that requires a ground (I believe that color green is used for grounds throughout the bike). Anyway, I don't think it has anything to do with your charging problem.

If you're putting out a charge at 3000RPM (~13.5 to ~14.5 volts) then your charging circuit is good. I'd suspect the battery.

[JPSmee]

SUCCESS!!!

So, after banging my head against the wall all this time, I figured out what the problem was. The brushes that provide power to the rotor had deteriorated. I ordered some new ones, and voila, no more draining battery. Just in time for Spring!!!

[alehman]

excellent! also, that green wire you pointed out doesn't go anywhere.