No crank - 2012 1199S

Hi guys,
I have an interesting one for you that I can't get my head around.
Recently, I changed my battery and the bike was fine, no starting problems. I had a track day and again, no problems at all.
The bike sat in the my garage for six weeks without being started. I went to start her up, and no crank.
I can hear the solenoid "click" but no start. Headlights didn't seem dulled out like a traditional discharged battery.
Voltage at the battery was 13.6 and when attempting to crack would only drop to 13v
I connected the battery to a charger (just in case) and after 15min bike cranked and started.
I left the charger off for a couple of hours and again same symptom of clicking but no turn. I measured the voltage this time, from the main power cable on the starter and it only measured 10v when trying to crank and still the same 13+V at the battery = somewhere between the battery and stater there is a voltage loss.
I checked the main negative earth cable and it seems ok with very little resistance drop.
My experience with a discharged battery is not the same as this. Dim lights, slow turning engine. These symptoms seem different.
The voltage drop at the starter motor makes me wonder if it's the starting solenoid or even the starter motor?
Starter motor is $800, so really don't want to replace without having some confidence that it's the starter.
Any help would be appreciated.



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My 2013 is in the shop for same reason. Haven't heard back yet.

What battery are you using? Brand and model.

Mine is oem at the moment. I have a lithium battery but haven't changed it. This is definitely not battery related. Maybe a component of the charging system but not battery.

I’m guessing you need a new cable that goes from the battery to the starter and solenoid. Perhaps also need a new cable from the alternator to the battery/ rectifier. I suggest checking the battery voltage right at the positive terminal and then check it at the starter. If you see a difference between the two places of half a volt or so, could be a bad cable. How do I know this? I’m a Porsche owner and it’s quite common problemon 997.1 models. It cost me 1400 dollars to get fixed.

Lithium battery
Ultra batt twin plate.
Like I said it was fine up until a week ago.


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I was lucky enough to find a starter motor locally and the dude was kind enough to let me fit and try it.
Spun over first time with no problems. No more "clicking".
Part numbers was one number different between the one I removed;
4280009182
To the replaced motor;
4280009183
What I also noticed was how ...... the earth cable from battery to motor was. Not crimped properly and showing signs of corrosion.
I will be changing all the power cables, from battery to solenoid and solenoid to starter and earth cable with 4 gauge, oxygen free wire.
Also noted that the earth cable lug on the engine side is fitted between the earth bolt and washer and NOT the engine. After fitting the 4 gauge wire, I will be fitting the lug between the engine and washer.




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The bad exposed crimping on the cables causes a voltage drop, which then causes more current to flow and more heat. That of course all causes the cables to degrade even more and affects the starter over time. It’s the same thing in 997.1 Porsches. So yes good idea to get new cables and I would flow solder them too where the crimping is done before you install them.

Volt drop, high resistance, low current
low resistance, high current

Ohms Law

A electric motor requires power as determined by its load impedance both from its own internal resistance and its mechanical load, so when the voltage drops due to a bad cable the current has to go up to make the same amount of power available. Voltage drop by bad cable means more current has to flow. More current means more heat too. Heat breaks down insulation. Insulation degrades and it opens the cable to moisture. I’ve used Maxwells equations, ohms law, Fourier transforms, Bessel functions, Eigen values and things most people heard of for many years now. But two more to go and I’m out.

I know I just wanted to see the full answer