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Discussion Starter #1
So this morning I tried to start the bike and it turned over a few times then I was out of battery power to start it. Had to jump it with a car battery.

I still took it to work (about a 10-15 minute ride), knowing well that I might have to come back in a taxi... but I had no other choice and it was getting late for work, so I rode the bike and got to work just fine.

When I got off work I told this guy who works there that my bike might not start so if I had to leave it there, to please keep an eye on it and I'd come back later to get it.

Went up to the bike and it fired right up, not a second of hesitation!

So I know the bike is charging the battery, cause I've measured the voltage and the bike puts out 13-14.5 Volts measured at the battery terminals. Also because the battery got a good enough charge to start the bike after just a 10 minute ride.

So what else could it be? Bad battery? Electrical draw even when the bike is off? How can I tell what it is?

I'd like to add that both times this has happened, it happened after the weekend... I don't ride my bike during the weekend.
 

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Could it be the brown wire you changed around last week?

If you think there's a draw, take a battery cable loose and touch it to the battery with the key off, see if there's any spark when you touch the terminal to the battery.
 

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Discussion Starter #3
It shouldn't be the brown wire since it comes from the R/R and not the bike's wiring... also because it's only supposed to be a sensor for the RR, but I'll check it anyway. I'm gonna try that and see if it sparks.

I do have more connections there than I should... I grounded a pin on the junction box to bypass all the safety switches and I put in the coil relay... and possibly something else that I don't remember.
 

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If you have a VOM or a test light check it for parasitic draw. Its easy. Take the positive cable off the battery. One end of the VOM or test light goes to the battery post, the other to the cable. If the VOM reads current or the test light comes on you will have found your problem. Engine off, key off.
 

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Discussion Starter #5
If you have a VOM or a test light check it for parasitic draw. Its easy. Take the positive cable off the battery. One end of the VOM or test light goes to the battery post, the other to the cable. If the VOM reads current or the test light comes on you will have found your problem. Engine off, key off.
That would be... one end of the VOM to the negative post and the other to the positive cable that I disconnected? Or the VOM between the positive post and the positive wire I disconnected?
 

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Positive post and positive cable. Probably best to use a test light, leave it hooked up where it is easily seen . Disconnect things/wires till it goes out. Doing automotive repair I start by pulling one fuse at a time.
If the light does not come on, you have no parasitic loss AT THAT POINT IN TIME. I am yelling from frustration at myself.
 

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Discussion Starter #8
How far do you ride to work? It's possible that even though the bike is charging the battery when it's running, your not running it long enough to fully charge the battery.
It's only a 10 minute ride... maybe around 4 miles.

Really sucks that my battery tender got fried. I'll try to replace it as soon as possible.

I don't have any problems during the week though, just when the bike sits for the whole weekend.

I tested it yesterday, precisely because it happened last week, but it started fine. However, it was already warm outside and when it's cold (like this morning) it has a bit of a harder time starting.
 

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It's only a 10 minute ride... maybe around 4 miles.

Really sucks that my battery tender got fried. I'll try to replace it as soon as possible.

I don't have any problems during the week though, just when the bike sits for the whole weekend.

I tested it yesterday, precisely because it happened last week, but it started fine. However, it was already warm outside and when it's cold (like this morning) it has a bit of a harder time starting.
How cold was it this morning Ceal?
(I suspect what you call cold, and what I call cold are not the same thing. ;))
 

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Discussion Starter #11
How cold was it this morning Ceal?
(I suspect what you call cold, and what I call cold are not the same thing. ;))
Definitely so. I just meant in relation to what's hot here.
 

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Yeah, 4 miles might not be enough to fully charge the battery. It's likely real close, just enough to get it to start every day, but a battery does lose a charge slowly while it sits. Two days over the weekend might be enough to get it down that last bit so the bike has trouble starting.

You need to ride longer coming home from work or get another battery tender ...
 

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just a shot in the dark here, but see u put in a coil relay? , maybe u hooked the relay to a constant power source ??? that would cause a slow drain on ur battery
 

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forgive me if this info was stated already.....
What battery do you have and how old is it?
How did you "fry" your battery tender?

I am thinking there might be a internal short on a cell of the battery. Did you load test the battery?
Cold will cause the plates internally to warp and possibly short causing the battery to "leak down". in warmer temps, the plates might not be warped the same amount and the problem goes away.
This could also have contributed to damaging the tender....just sayin.

If it's a wet cell battery and is older than 3 years old....replace it...jmo
 

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Discussion Starter #15
Thanks for the tips and info guys! I'm gonna head out to the bike and check all this stuff.

The battery is an Everstart AGM, which has been awesome. The "cold" here is just a bit below freezing at the lowest in winter and only a few days. Right now it's not cold at all, just a bit cooler in the mornings.

I think the battery tender stopped working because of the outlet I put it in, it's quite questionable. Should have used another outlet. I had already owned the tender for maybe 2 years or so. Same time with the battery some 2 or 2 and a half years.

I was already thinking of checking the coil relay. I remember I checked it when I put it on to make sure it only activated when I turned on the key, but I'm still gonna check it again and see if nothing has changed.

I don't know of any place that will do a load test on my battery. The only place I can think of is autozone, but I've never seen any sign that they do it here. They won't even check computer codes anymore since they seem to have "lost" some of the harnesses and won't replace them.
 

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x2 thats also a possibility
 

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Discussion Starter #17
Could it be the brown wire you changed around last week?

If you think there's a draw, take a battery cable loose and touch it to the battery with the key off, see if there's any spark when you touch the terminal to the battery.
You nailed it, it was that brown wire. There was absolutely no spark when touching the terminal to the battery though.

If you have a VOM or a test light check it for parasitic draw. Its easy. Take the positive cable off the battery. One end of the VOM or test light goes to the battery post, the other to the cable. If the VOM reads current or the test light comes on you will have found your problem. Engine off, key off.
This procedure however, allowed me to determine that the brown wire was indeed drawing some current from the battery. I measured voltage between the positive battery post and the cables I had directly connected to it. Since I have two different cables going directly there (the usual positive wire and the one I sent there from the R/R), I could pinpoint that brown wire easily.

If I just disconnect the brown wire I get wayyy too much voltage going to the battery, up to 18V. If I connect it to its normal place towards the JB, I still get 15.9V. So since I needed to send voltage to this wire to keep my battery voltage below 15V, I spliced the red wire onto the coil relay output, which only turns on when the key is in the "on" position.

So now I get no draw from the R/R when I park the bike and I still reduce the voltage to a nice ~ 14.5V :)

Thank you guys for your advice! Everything worked out great.

Now I'm gonna see about hooking up my new R/R. It's not a mosfet (stupid mistake) but it's certainly many many years newer than my current R/R.
 

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Discussion Starter #18
Well... funny how things work out.

Turns out that my new R/R didn't need that brown wire anyway. The new R/R does have the pin for it, but if I leave that disconnected I get 14.7V at any RPM!

At start up, it gives me a bit lower values, around 13V, but as it warms up (and doesn't take long, just a few seconds) it gets up to 14.7V and holds it right there.

So maybe I didn't get a mosfet (I think) but I got about the same results!

My inexpensive multimeter says that once it's warmed up, I get 14.72-14.75 volts. Revved up the engine and never saw it go past 14.75V.

The new R/R does get just as hot as the old one though, so I'm assuming this is normal then. The wires are staying nice and cool though, so I don't think I'll have any more trouble with the insulation melting on them.
 

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14.75v. Hopefully that will come down a little when the battery gets charged.

If that continues, I would have to load test the battery.
 

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Discussion Starter #20
14.75v. Hopefully that will come down a little when the battery gets charged.

If that continues, I would have to load test the battery.
Why?
 
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