Bad Battery

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BTW, the battery is a new Yuasa and is fully charged. I'll start pulling fuses and see if I can find a problem.
Yes, do that. Just a suggestion but I would leave the battery ground strap disconnected until you find the source of the parasitic draw. Running an AGM battery flat doesn't do it any good!

 
My Amazon sourced battery, labeled Yuasa is just about 3 years old and about to die on me. Original Yuasa lasted 7/8 years. Go figure.

The philter eBay type above for $39 seems attractive.


Well, the Yuasa copy died on me. Just gassed up, wouldn’t restart.

S.....O.....A......B

Luckily, wifey was at home just around the corner, so she came along with car and leads.

One more try.....she started! Rode home, switched off, wouldn’t restart.

Guess it’s time to install the Caltric battery I bought for $39 two weeks ago!

When I recover from the beating wifey handed to me.

 
^^^

Sure you don't have a problem with the switch, starter relay or battery connectors?

It could very well be the battery but I would at least give it a slow (2 amp rate) charge let it sit for a couple days in case of an internal "soft" short and then get it load tested.

If the cause something else, you may be faced with a repeat performance in a week or so.

 
Good advice RossKean though I have had it on the battery minder regularly, a few days of not riding and she turns over noticeably sluggish before firing up.

Tried to turn over after getting gas as above and after getting home but just not enough power there to spin her over.

Dvm shows 12.6v across the terminals though as I understand it, that’s no indication of amps available. Correct?

I am out of town now, not on bike, but will have a closer look when I get back.

Thanks for the suggestions.

 
12.6 V is absolutely no indication of amps available. See what the voltage does while cranking. If it drops very low, it MIGHT be the battery or (see below)...

Another thought - quite possible that your starter motor is on the way out. The only real diagnosis for that is to use a clamp-on DC ammeter on the battery lead while cranking. You will see something north of 100 amps if the starter is going bad. You might replace the battery an it could work for a time but the starter won't get better (if that is the root problem).

Note: If the resting voltage is 12.6 V (after not riding or charging for several hours), it is not indicative of a full charge. A fully charged AGM should read around 13 V, after a couple hours off the charger to let surface charge dissipate.

Before anything else, take the battery off the bike, charge it fully, let it "rest" 24 hours, check voltage and have it "load tested".

 
Since I ride year round, I’ve never had the need to put a tender on. I’ve had just as good service from batteries plus batteries, but I order a specific battery. They sell different qualities (I’ve had the stock guy bring me me and had the manager stop him, noting that I ordered a higher end battery. My 2014, purchased new, ridden daily, started stumbling at start after less than two years. Put a BP replacement in and no further issues(knock on wood) at almost 70,000 miles.

 
12.6 V is absolutely no indication of amps available. See what the voltage does while cranking. If it drops very low, it MIGHT be the battery or (see below)...Another thought - quite possible that your starter motor is on the way out. The only real diagnosis for that is to use a clamp-on DC ammeter on the battery lead while cranking. You will see something north of 100 amps if the starter is going bad. You might replace the battery an it could work for a time but the starter won't get better (if that is the root problem).Note: If the resting voltage is 12.6 V (after not riding or charging for several hours), it is not indicative of a full charge. A fully charged AGM should read around 13 V, after a couple hours off the charger to let surface charge dissipate.Before anything else, take the battery off the bike, charge it fully, let it "rest" 24 hours, check voltage and have it "load tested".


Hi Rosskean. So finally took your advice and got the battery charged up, then took it to local car parts store for load testing. They say it’s good!

12.6 volts, 207 ca. Re-installed on the bike making sure connections are good but still having same issues, slow and/or labored cranking.

I can borrow a clamp on DC ammeter from work and I guess some plastic removal will be needed to access cables. Should I be checking any other stuff first, would you say?

The bike has really low miles for the year, is it really possible the starter could be playing up?

Thanks for any more advice you can give.

 
Still two possibilities

Starter motor - high current, labored cranking, especially when hot.

Starter solenoid could also be an issue. I haven't done so but you should be able to use something to jump the solenoid to see if bad contacts are the culprit.

Good luck! - at least you didn't needlessly replace the battery!

 
Thanks again for the input.

So yesterday, after battery on the bike had been hooked up to the battery tender overnight via the pigtail, then tender unhooked for a time, battery was showing 12.9/13 volts.

Hooked up DVM to the pigtail and hit the starter. Engine cold, spun over somewhat slow and voltage dropped to around 9.5 for a split second before she fired up.

Other thing, kept her running to get the four bars coolant temp, and up to 3000 revs DMV only showed 13.5 charging volts max.

Going by some other posts I read, that seems a little low, would you agree?

 
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Dip is a bit excessive, and charging voltage should be 14.1V or more after several minutes. Both of these leads me to believe the battery is no good regardless of what the load tester said

 
Dip MIGHT just be due to excessive current draw - if the starter is pulling 100+ amps, the battery won't hold voltage. I think a cranking current test (hot) is still needed. It could take more than the few minutes (to get to 4 bars) for the voltage to get back to 14V after a high current start and his older bike may also be suffering from the voltage loss issue that dcarver ran into. (I don't see 14V on my '07, even with a fully charged new battery - will be interesting to see what I get on the '11.)

dcarver's thread:

https://www.fjrforum.com/forum//index.php/topic/146331-krzy8-gen2-charging-circuit/page-1?hl=roadster

Huge thread but the synopsis is in the first post. Issue solved with aftermarket wiring harness for $60 or so.

Not saying it can't be the battery but the starter (and possibly solenoid) should be verified; certainly before replacing a newish battery.

 
13.5 volts at the battery posts is the most I have ever seen on my '07 in 10 yrs of ownership. Details: Fluke meter, new battery or 10 y/o, anywhere from 2500 to 7000 rpm. 13.5 Vdc max.

 
Always seen 14.2 on all of my FJRs. Latest one often shows 14.3 under normal running (and within a few seconds of starting whilst on fast idle). Factory spec is 14.2 to 14.8, though I've never heard of anyone measuring anything above 14.4.

 
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Thanks again guys. Just got to make time to run the clamp on ammeter test now.

Interesting point from dcarvers thread,

9. Measured VDC across battery unloaded then with key on, 200 mVdc drop. Not bad

Just tried mine. 12.8 v ignition off, 12.4 and dropping slowly ignition on. Off again, slowly recovered to 12.8.

 
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May be a weak battery, may be a starter issue, may be some of the voltage drop stuff demonstrated by dcarver. Quite possibly a combination of all three. Get the current draw test run and decide on what to do from there. Good luck.

 
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