Stator test

[memper]

Bike has sat for three weeks because I went camping. Taking a small trip two hours away and I wanted to check my charging out. New shindengen mosfet, new lifepo4 battery (a few months old).
At rest with the bike on read 12.3 or something like that
At idle it went up to 13.1 and then a little while after (turned the bike off and repeated the test) it went up to 13.6 at idle.
Revving it went up to the low 14's if I remember correctly. This seems "normal".
Stator tested .4 on all three wires.

My question is what can I do to make sure my battery isnt in the process of getting stuffed again? I'd hate to be on the highway and have another melt down.
I'm thinking just go for a short ride around town and test again after and if the charge keeps going up then I'm stuffing it. Sound right?

[Howie]

At this point the only field test for a lifepo4 battery is open cell (no load) voltage.  Fully charged is about 14.3 volts, 50% 13.1 and the battery can be difficult or worse to bring back to life if it falls below 12.7.  Though open cell voltage measures state of charge, not capacity, if the battery does not successful charge to 14.3 it is toast.  As of now further testing needs to be done by the manufacturer.  This is one of the reasons I did not buy one.

Ummm...Did the bike start?  Low 14s is a proper charging rate.  A rise in charging rate when the bike is warm is not abnormal.  Just make sure it does not go over 14.5.

[memper]

Yeah, a bit difficult to start at first but to be expected considering how long the bike sat. I think it's probably fine and I'm being paranoid from my previous rr failure.

Ah, I just remembered that after sitting a while the lifepo battery chugs a bit at first start and gets warmed and delivers strength upon further starting.

It's fine. I guess it helps to sometimes think out loud here.

[memper]

So I took my trip and when almost to my destination the battery failed. All went dead. Fuel pump would run and the rpm would cycle but not enough power to turn over. So I bump started it and I continued on to my destination. The power cut out once again while in town, and another bump start to get to the hotel.
I promptly called the nearest bike shop and had them put a gel battery on a charge. It charged at the shop for a couple of hours and when I went there to install it they said it was fully charged.
I rode home and stopped at a gas station just outside the Holland Tunnel. Same weird symptoms. Electrics would turn on but not enough juice to start. Bumped it and rode home.
That said I'm done with LifePo4 batteries. Enough is enough...

My thoughts:

1) Perhaps the new battery wasn't charged fully? Can two hours really be enough to charge a new battery?
2) Maybe I misread the meter when checking the stator? I got .4 Ohms on each wire from the stator (bike off) and the original battery was taking a charge. Got "OL" reading (bike off) when checking if the stator was shorted to ground. *This test was done prior to leaving*

[Howie]

The charging system should have at least maintained the charge when the battery was put in the bike.  You have a charging system problem.  To be sure the gel battery is good, fully charge and load test.  There is more to your charging system than the stator.  Do check voltage drop over all connections including ground!

[memper]

Pain...
Every video I've seen about testing the charging system it has included the stator, battery, and r/r. Is there more? I have no idea how to test voltage drop over all connections. But I'm always learning something new on DMF!

[Howie]

Yep, all the wires and connectors in between.  These should help.  They are for cars, but the important differences are your rectifier is in the regulator, not the alternator and your alternator uses a permanent magnet.  

http://www.maniacelectricmotors.com/chstsycivote.html
http://www.aa1car.com/library/voltage_drop_testing.htm


Oh, I assume you know about the regulator fuse?

[memper]

I will check those links as well as that fault finding flow chart you've posted. Thanks Howie. Hopefully I can get to it this week.

[brad black]

http://www.bikeboy.org/chargingsystemdiagnostic.html

might help.  work you way through it step by step.  being methodical is important.

[memper]

My findings:
Took apart all connectors and the looked good except for a small burn mark on the fuse that came with my mosfet on the positive battery side. Checked the fuse for continuity and it zeroed out signaling a good fuse.
RR checked out fine.
Stator read .3/.2 across the three wires. All were the same but I'm not sure if such a low number is bad.

New battery reads 13.3 dcv

Started the bike and at idle it read 14.2 dcv
Revved to 3000 rpm and it went up to 14.27
Revved to 5000 rpm and it went up to 14.27

According to the electrosport flow chart my charging system is ok.

What I did notice is that when taking off the fuse the positive wire was a bit loose. Could it have created an arc and caused my problems?

[Howie]

Yes.  Or just plain ordinary open circuit.