Intermittent dead short while starting

Whoops 

I am only going the "lithium" route on my build because of space, otherwise I'm a fan of AGM. Just my opinion but I put "flooded wet battery's" in the same category as wooden wheels (they were great at the time but the world has moved on)

This happens when the lithium battery is underrated for the application it's trying to do. Too much amps drawn, too small a battery. Best off using a lead acid battery or possibly a larger capacity lithium if available. I highly doubt an intermittent short or any other electrical problem on the motorcycle.

Thanks everyone for the insight. The battery brand is Ampxell, and the manual shows 120A max constant discharge current. 

Here is a photo of the battery model and specs.



The previous two batteries were a brand called X2 power that I got at my local Batteries Plus store. That manual unfortunately gives no useful info besides the charging min and max voltage.

Whilst the "capacity" isn't massive it shouldn't cut out on the current being drawn by your starter (for a couple of starts at least without  re-charge)

@Wookie58 I'm glad your train of thought matches mine on this battery. Although, I had it hooked up to the charger all morning and it was reading 12.3V across the terminals but when I attached the + & - cables, I had no power to the bike. Removed the cables from this battery and hooked another 12V battery to the cables and without starting the motorcycle, I had all my lights. 

Having the same electrical problem with three total batteries, two of which are different models and capacities certainly makes it hard to believe for me that it's the battery. There is a local shop in town that rebuilds and services starters and alternators so I plan to see if they'll take a look at mine.

My understanding is that LiPo batteries require a different charge voltage.  I have them on my RV and I bought a charger that provides 14.6 volts.  It's specifically made for LiPo batteries.  The RV batteries won't fully charge on a regular charger.

The battery's bms may be seeing something it doesn't like and shutting down. I'm just spit balling but you could have AC voltage from your alternator leaking past your reg/rec.

SLA/AGM batteries are heavy and inefficient but are simpler without the battery management system.

I would put an agm battery inside to see if the issues persist.

Put a voltmeter probe on your positive battery post and another on the positve post on the starter.

meter on DC V
key on

push the starter button.

your voltage should be 0.0v
any higher than 0.5v then you have too much resistance on the positive wire from the battery to the starter.

move one probe to the negative post and the other probe to the starter mounting bolt. Press the starter button.

Voltage should be 0.0v as well.
This will check the quality of the ground circuit from the negative terminal to the mounting bolt on your starter.
 

There has been some good ideas offered in the thread on your issue. Lots of what has been stated would point me towards the issue being what the starter is seeking and on what the new battery's protection circuit requires.  I think that when faced with issues like this, one needs to measure amps not volts in any attempt to find the solution to the problem.  The starter by far is the largest draw on the electrical system on bikes. Keep in mind that the starter is seeking a certain about of watts (volts x amps = watts) to function correctly. The starter does not care how it gets what it is seeking. It not enough volts it will attempt to pull more amps, or if not enough amps it will attempt to pull more volts. I am sure you could make use of an amp meter to aid in your testing. But have found this simple tool one can make for testing and use with a VOM.. I did not come up with this tool rather it comes from Mike Nixon's site  motorcycleproject.com      See attached


 

GD4now that is a great article, if anyone is looking at going this route but doesn't feel confident around the level of accuracy required to make this shunt there is an alternative from the marine world

Yeah, a current reading would be nice. I have a fluke 376fc amp clamp in my backpack. So I understand the benefit of that measurement. My KZ440 pulls 70amps.

The voltage measurement was just eliminating the wiring and ground connections to the starter as an issue. 
He most likely has a voltmeter so the readings could be taken quickly.

F64 wrote:

Yeah, a current reading would be nice. I have a fluke 376fc amp clamp in my backpack. So i understand the benefit of that measurement. My KZ440 pulls 70amps.

The voltage measurement was just eliminating the wiring and ground connections to the starter as an issue. 
He most likely has a voltmeter so the readings could be taken quickly.

Absolutely right. I think given it will start from a conventional slave battery I suspect the starter of being "on it's way" and the BMS doesn't like it ??