I've witnessed lithium batteries shut off if shorted or overloaded, and read zero volts. Then pop a charger on the battery for 10 seconds and it comes back as if nothing happened. You might have a charging system shorting out.

12.7 volts running seems low.

Edit- don't disco the battery. But your voltage does seem low. Basically a shelf battery voltage.

 

I've witnessed lithium batteries shut off if shorted or overloaded, and read zero volts. Then pop a charger on the battery for 10 seconds and it comes back as if nothing happened. You might have a charging system shorting out.

12.7 volts running seems low.

Does the bike run with the battery disconnected? (start the bike and pull off the battery leads, careful not to short them together)

With a new battery installed, bike starts up fine at around 12.8 volts. The voltage never changes from the time I start the bike and throughout revs. I pulled the negative lead off the battery and the bike died right away.

 

Reading the above it seems your alternator diodes are Kaput, or youve lost a phase inside the wiring of the thing. You should be seeing ~14.3-14.6v at the battery at about 3000rpm, 12.4v at rest. Seeing a continuous 12v regardless of rpm means your alternator isn't charging the battery.

These bikes are canbus and relatively sensitive to correct voltages, so if not enough, it will shut down to protect itself (ECU etc).

I think the battery might still be good enough, but needs to be tested on a carbon pile or quality battery tester. A lithium with in built bms will also protect itself by simply switching off if they get drawn down too low (e.g. below bms min voltage set point) if new, might be worth having it tested.

Dont just drop a new battery into it, as defective alternators have been known to drag brand new batteries down to failure really fast (cars and bikes).

An auto electrician would be able to confirm a failed alternator. Replacement diodes or alternator rewinds are possible. Also check all the earth connections.

Last point, remove the alternator and starter motor and clean them out with compressed air, carbon dust etc. can cause trackinh and spurious voltages. With the starter motor, you need to remove the outer cover to expose the windings, and add a bit of bearing grease to its bearings.

Best of luck mate

 

So removing the alternator and taking it to say... AutoZone... To have them bench test it, it should function the exact same as a regular car battery?

 

Alternator functions the same as a car's alternator. Similar size engines in some small cars.

An auto electrician can test the diode and check for continuity (resistance) in the wiring. If you have a multimeter, you can check if the wiring has a fault by measuring resistance between each phase and ground. Infinite resistance (Ohms) in any phase indicates a broken wire, as there should be some resistance. I'm not sure how to check diode function, hence the suggestion to take it to an auto electrician.

Get the battery checked as well as suggested.

 

Going to go ahead and pull the alternator tonight, thanks for the input.. definitely makes me feel better about pulling it out. I'll keep you posted!

 

If you have access to a GS-911 or a moto scan, that might save you a lot of time troubleshooting.

 

I fried my alternator diodes by starting the bike w/a 10 amp charger on it, FWIW.

Fortunately a replacement alternator was "cheap"

 

I fried my alternator diodes by starting the bike w/a 10 amp charger on it, FWIW.

Fortunately a replacement alternator was "cheap"

Going to go ahead and pull the alternator tonight, thanks for the input.. definitely makes me feel better about pulling it out. I'll keep you posted!

An alternator repair shop might be able to source the regulator rectifier parts of yours.
Blown lights are a symptom of over charging so voltage reg not rectifier.
Ebay is your friend.....maybe?

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I had good luck with eBay.

Stick it in, if it doesn't work, return it (if the seller stated anywhere that it's working)

 

A long list to remove the alternator.

 

Oh don't scare him.

I removed the gas tank on the side of the road using only the tools on the bike (and a 6mm allen key that I now put in the bike).

Mostly it's removing the tupperware.

 

Got the alternator out, try to take to my local shop to do a bench test but since it's not pulley driven... Any way to test it with just a multimeter? I'm not really seeing an easy way to get to the windings.

-took a stab at it.... Took the cover off, it looks like these are the windings. I have ~.1ohms resistance between the windings. I took each one to ground and also have continuity... That's pointing to a bad alternator right?

 

Got the alternator out, try to take to my local shop to do a bench test but since it's not pulley driven... Any way to test it with just a multimeter? I'm not really seeing an easy way to get to the windings.

I tested it by installing an ebay alternator and seeing that it was charging.

I did this without even installing the gas tank, just running off what's in the lines. Use the multimeter across the battery to see if you have nice juicy volts

 

To my understanding, you should not be seeing any continuity (resistance) between windings. From each winding to ground should also be infinite or open circuit,, to my knowledge, current flows to the negative terminal not to ground.

Seems to me the alternator is the issue.