Is it Dead?

Came back from a ride yesterday, got distracted and left the key on. Came back a couple of hours later to get something out of the top case and saw that key was on and everything was dead. Said things not worth repeating! Plugged in Battery Tender and left it on overnight. Now showing close to 80% charged. Bike has 36,000 miles, mostly long trips.

Yes, the quick answer is replace it. Are there easy ways to check if the battery is okay? I use old motorcycle batteries in a starter for my RC airplanes. Have run them flat a few times and they recover. Arthritic hands mean a trip to the dealer to get a new one but would like to ride until a service scheduled 3 weeks out.

Yes, I did search on NEPRT. Found a few "dead battery" threads but not the answers to my question.

Pretty good chance that the battery will survive just fine. Charge it fully and then let it sit at least overnight and see if it is still OK. Might not hurt to get it load tested. While letting an AGM battery go flat is not good for it, it certainly isn't (usually) the kiss of death. I had at least three or four instances where I left the key on for my '07 over the years - and came back to a flat battery. Ultimately got 10 years and 175,000 miles out of the OEM battery.

Same thing happened to me. I knew the battery was three or four years old, so it was time to step up and buy a new one. It's one of the few things I still get from my motorcycle dealer, though it was just about $150. The service department put the battery load tester on it and it showed just barely okay. I'm heading for a two-week ride including Tucson and the Grand Canyon, and I'm not in the mood for this kind of a problem. Also they will recycle the dead battery for you.

A load test will tell you if the battery is good or bad. Let the Tender finish charging the battery before doing the test. Harbor Freight has inexpensive load testers. I have a Clearwater Voltage Sentry on my FJR and it tells me of the battery is accepting a charge - works great and I am confident I won't get stranded by a dead battery.

Fontanaman said:

A load test will tell you if the battery is good or bad. Let the Tender finish charging the battery before doing the test. Harbor Freight has inexpensive load testers. I have a Clearwater Voltage Sentry on my FJR and it tells me of the battery is accepting a charge - works great and I am confident I won't get stranded by a dead battery.

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Also places like AutoZone will load test for free.

They no longer do for motorcycle battery last time I asked.

It's a battery. If it's an expensive battery, it's still $200. Small, small price to be sure of reliability.

Yeah, it's a battery. But the load test for a car battery that's supposed to put out 650 Amps is a bit different than the test for a motorcycle battery, and as they "upgrade" their shop equipment, they may not have anything that tests "only" a couple hundred amps. Just a guess, but I can see how it might be like that.

Edit: I was thinking the post above mine was criticizing the Autozone no-bike-batteries thing, and re-reading, he's just saying no big deal to replace one that is suspect. My bad. I'll get my coat now...

How much do you like gambling?

Yeah, the battery might be okay and last for a couple more years. OTOH, it is four years old and it WILL fail at the most inopportune time in the middle of BFE somewhere. I would replace it...or keep the AAA card handy.

~G

Small side track: Twice now Ive called AAA for the FJR, and twice theyve shown up unprepared to tow a motorcycle. $40 Canyon Dancer too much investment I guess.

My most recent battery is a Shorai lithium iron. Unbelievably small, light, and powerful all nice for something so high above CG.

I bought one of these and it's been going strong for a couple of years. Certainly cheap enough.

https://www.batterysharks.com/SearchResults.asp?Search=yamaha+FJR&Submit=

redzgrider said:

Small side track: Twice now Ive called AAA for the FJR, and twice theyve shown up unprepared to tow a motorcycle. $40 Canyon Dancer too much investment I guess.My most recent battery is a Shorai lithium iron. Unbelievably small, light, and powerful all nice for something so high above CG.

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Another small side track: the AMA cost less, has better coverage and the one time I called for their roadside assistance they were prepared to tow a motorcycle. https://www.americanmotorcyclist.com/

rbentnail said:

redzgrider said:

Small side track: Twice now Ive called AAA for the FJR, and twice theyve shown up unprepared to tow a motorcycle. $40 Canyon Dancer too much investment I guess.My most recent battery is a Shorai lithium iron. Unbelievably small, light, and powerful all nice for something so high above CG.

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Another small side track: the AMA cost less, has better coverage and the one time I called for their roadside assistance they were prepared to tow a motorcycle. https://www.americanmotorcyclist.com/

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I think AAA just contracts with auto tow companies and it'd be a crap-shoot whether bubba shows up properly equipped. I think AMA and other orgs (like HRCA, e.g.) contract largely with bike shops, or at least require the operators to be properly equipped. The one time I got stranded (Seattle: ST1100 with what turned out to be a dead battery) I was a member of HRCA. I called them and a local Honda shop came out with a truck/trailer.

K_Flyer - Did the battery charge up and the bike run OK?

Personally, I don't see the point in replacing a functioning battery if it isn't showing any symptoms of imminent failure.

1. I look for evidence of a "soft" short (high self-discharge rate) - apparently charging OK but weak after sitting for as little as a few days. For this, I would replace battery immediately - could be one start from total failure. (Self-discharge rate for a healthy AGM is very low.)

2. Reduced cranking amps - either from a load test or observation of cranking speed. If you aren't sure, see if it turns over a lot faster using a jump start battery to augment the bike's battery.

3. Reduced reserve capacity - may start OK but maybe not so well on subsequent starts unless allowed to run for a while. May fail to re-start the bike if key (and headlights) are left on for as little as 5-10 minutes after shutdown via kill switch. This is the reason why I eventually replaced the OEM battery on my '07 after 10 years.

If none of these raises a red flag, I wouldn't consider replacement. (Would you replace a car battery if you left the lights on for a few hours?)

I carry a compact lithium-ion jump starter on trips. Not because I am afraid of random battery failure but more because of the possibility of a brain-fart (leaving the key on). I do a fair amount of MC camping and don't want to find myself stranded. So far, I have only used it a couple of times at work to jump-start cars where the owners had a failed battery or left accessories on.

redzgrider posted: It's a battery. If it's an expensive battery, it's still $200. Small, small price to be sure of reliability.

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Yeah, but $200 is enough gasoline to last all riding season for many Forum members. Test the battery, KFlyer, before tossing it.

^^^^ Not to get off-topic Hud. But seriously...that's enough fuel (at west coast prices) for like, what, a short one week trip??

~G

escapefjrtist posted: ^^^^ Not to get off-topic Hud. But seriously...that's enough fuel (at west coast prices) for like, what, a short one week trip??

~G

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Not to stay off-topic, but no one is forcing you to live there, sir. Gas is exorbitant here at $2.15 or so, and I'll be reporting on Upper Midwest prices in June.

FWIW, two climbing/hiking trips to Mount Rainier have convinced me that you have the better deal when comparing scenery to gas prices.

So OP... What did you do?

Battery was on the Tender overnight. Friday morning the tender was showing battery was fully charged in storage mode. Removed Tender and went away for Easter (in the car). Got back late Monday with no time to check it out. Tuesday morning decided to go for a ride so turned on the key, waited for the start up sequence hit the button and the bike fired right up as usual. Noted that the clock was wrong so the battery had been really dead. Twice later that day did a restart but with the Motolights on (They come on with the ignition.) and all was normal.

Will probably try the Reduced Reserve Capacity test as soon as I get some medical crap out of the way.

Thanks for all the help, including the off-topic comments.

Somewhat off topic but we love these bikes more than we ever loved one of our Beemers!