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The starter doesn't seem to crank the bike as rigorously as it used to. The battery is almost two years old, and I'd like to load-test it. I have an analog VOM, and don't have a carbon-element load tester. Because the bike still cranks and starts in a few seconds, I'm not confident there'll be enough time to see the VOM's needle settle before the engine begins running and I have to release the start button.

Thus, I'd like to disable the bike from running, but still allow it to crank. 5 seconds' cranking should give me a good idea of the battery's ability to deliver. The bike has no fuses to pull (save the starter's, which obviously must stay in place, and the extra fuse I added to power the heated vest controller).

Disconnecting the electrical connector on each injector should do the trick: with no juice, the injectors won't open, fuel won't be delivered into the intakes, and the bike won't start.

Am I missing something, or is this a reasonable method?

???? I don't know about disconnecting anything on start up. With all the electronic stuff going on your taking the risk that the bike might take it for a major problem and turn stuff off. Not a technical answer by any means, but your question shows you also have concerns.

Can't you take the battery out and take it to a parts store to load test it. If you lived near we could swap batteries to see if the motor spun faster.

Probably could, Harry, but I guess I just don't trust that I'll get an honest answer, as opposed to one designed to make me buy a replacement.

Did you try disconnecting the leads to the injectors? Curious and too lazy to try that myself to see the outcome.

How far you are from a BMW dealer. My local one will always let me drop in and load test the batter with the BMW battery tester and I do put some faith in that one. If pulling the leads from the injectors doesn't work, load testers aren't that expensive. Even harbor freight's version has proved its value for me . . .

Still intending, but haven't done it yet.

My son and his family have come to visit, and he brought his digital VOM. We'll give it a shot this week.

I think you could also disconnect the fuel pump using the connector under the seat if you didn't want to mess with the injectors.

My current battery has always seemed on the sluggish side and never cranked the engine over very well. (Deka ETX14). But its done this for 6 years now and has never failed to start the bike even in colder weather.

Disconnecting the injectors took about 90 seconds, including loosening the right-side triangular plastic cover for access. The test results were:

ignition off 12.3v
ignition on drops to 11.5, then over twenty seconds rises back to 12.3v
cranking drops to 9.8v, and stayed there for the 3 or 4 seconds I held the start button down

So if the battery is not bad, do you think your starter is going?

I doubt it. After a ride, or after a night on the charger, it cranks pretty well.
Still in wait-and-see mode.

Has anybody done the battery drawdown test on a 2017 model? If so please post the kWh values you measured. Im looking at buying a certified 2017 model and I was wanting a benchmark to see what the battery degradations were on these certified FFEs.

DBrick, frankly this all seems much ado about nothing. Presuming you have an AGM battery 2 years old,the fact it "doesn't seem to crank the bike as rigorously as it used to" is pretty subjective and nothing to really test against. Batteries vary, how is the charging system, is it up to snuff, is the fuel good? If the bike starts and runs good, I would not obsess over it, I sometime think my bike does the same thing, I change the battery at the end of every third riding season whether it needs it or not, better to have a new battery than be stuck in the middle of nowhere when i do need it. In either event good luck, let us know what you do.

Shermanexott, what is a battery drawdown test? Are you referring to a parasitic battery drain test? Why is it even relevant?

dbrick,
Being it was so long ago, my guess is that the battery was replaced soon after. Your readings:
"ignition OFF 12.3v, ignition ON drops to 11.5, then over twenty seconds rises back to 12.3v.
Cranking drops to 9.8v, and stayed there for the 3 or 4 seconds I held the start button down"

The ignition off 12.3V indicates a weak/discharged battery. Should be 12.54 or higher.
The 11.5V says you had a weak battery BEFORE using the starter. Should go no lower than 12.1 or so.
The starter knocked it down to 9.8V, strongly indicating the cranking voltage of a weak/discharged, ready-2-die battery.

Thanks, CycleRob. Actually, I've just kept plugging in the charger when the bike won't be (or hasn't been) ridden in two or three weeks. No change in behavior is tolerable. When things get worse, then yes, I'll replace it.