Tis the Season for Battery Failures

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Ignacio

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This is the time of year people start posting up about weird things their FJR suddenly start doing. Weird symptoms manifest and diagnoses bubble forth.

It's usually the battery.

A battery that survived the previous winter made it to the spring...just barely. And then did their job in the ever-warming easy-life summer, through the prime riding season, and through the warm fall.

But then, a brisk mornings or two and you go to turn the key. Your battery with no previous warning....falls on its face. This may vary with your latitude and local weather of course.

This time of year, it's usually the battery.

Have a great autumn and enjoy the colorful rides.

Ig

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This ti
 
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I've been dreading replacing the one in the car. My brother just had to do one on his (different, domestic brand) at it was $400!

Damned EVs eating up all the resources.
 
Just replaced three bike batteries, FJR, Wing, and Madura. The ones in the Wing and Madura still started the bikes but failed when I load tested them. I put the OEM batteries in the Wing and FJR. Rocky Mountain ATV had the best prices on those two, had them in stock, and shipped them very quickly.
 
This is the time of year people start posting up about weird things their FJR suddenly start doing. Weird symptoms manifest and diagnoses bubble forth.

It's usually the battery.

A battery that survived the previous winter made it to the spring...just barely. And then did their job in the ever-warming easy-life summer, through the prime riding season, and through the warm fall.

But then, a brisk mornings or two and you go to turn the key. Your battery with no previous warning....falls on its face. This may vary with your latitude and local weather of course.

This time of year, it's usually the battery.

Have a great autumn and enjoy the colorful rides.

Ig

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This ti
Not for nothing but… Battery Tender always. 4 years into my 2nd on my original ‘06 and only replaced the 1st b/c I happened upon a freebie. Still have the old battery jacked into an old Buell which is now finally about toast.
 
Not for nothing but… Battery Tender always. 4 years into my 2nd on my original ‘06 and only replaced the 1st b/c I happened upon a freebie. Still have the old battery jacked into an old Buell which is now finally about toast.
Battery Tender isn't everything. It is, however, important that you don't over-charge or run the battery flat. You should also avoid charging at an excessive current (less than 1.5 amps is best - C/10 where C is the capacity in ampere-hours). If you leave the ignition on and flatten the battery, the worst thing you can do is jump start it and go for a ride. Not only did you run it way down but the bike will dump charge back into the battery at far higher than the ideal rate. (But sometimes you don't have a choice - I have certainly done it.) AGM batteries are more tolerant of cooler climates than hot climates - owners in the South replace batteries more often than Northerners do. Note: I have seen a few batteries that were killed by battery maintainers that failed to go into "float" mode when the battery was fully charged or "float" was at too high a voltage. (I have also seen people use a "trickle" charger as a maintainer and absolutely destroyed their battery in less than a few weeks.)

I have NEVER used a battery maintainer on a motorcycle battery. I ride from late March to early December and the bike lives in an unheated garage. I usually leave the battery connected (FJR has a very low parasitic draw) and an AGM battery in good condition only loses a few percent of its charge per month (if not connected). I do give it a top-up with a slow (1 amp) charger for a few hours a couple of times in the off season.

My 2007 got 10 years and 165,000 miles before I changed it - reserve capacity was down but it still worked. The battery in my 2011 is still the OEM after 11+ years (but only 100,000 miles). It has been inadvertently fully discharged a few times and the original owner (who put just 36,000 miles on it) let it sit for almost two years. (Battery is a bit "tired" and will likely get changed next season - but I said that last year too.)
 
Battery Tender+ "trickle" charger here. Went from swapping Wing batteries every 2 years (failed at 2.5 consistently) to 4 years. Longer on the FJR. Tried to use it when flashing the RS3 and it couldn't keep up. Was at about 10% battery reserve when the flash finished. Went out and got an 15amp Battery Tender and it does well. Man, talk about battery chargers getting all fancy and stuff. This has a display instead of needles, shows battery % and more.

Still use the trickle charger version on any vehicle except when doing like above (long/big load with engine off).

My brother just had to replace the battery on his 2013 Caddy and it was $400! EV and inflation are driving up the cost of all this stuff. Ugh!
 
I have a built in prosport smart charger for the boat batteries that stays plugged in all winter. A 3-4 amp battery tender on my wife's convertible (expensive battery and a lot of electronics that seem to always be drawing power). The bikes have battery tender juniors that get plugged in for a few days each month to all month in the winter depending on how much work I am doing in the shop - cords get in the way.
 
Two further comments on battery maintainers...

A "trickle charger" is usually a dumb transformer that puts out an unregulated rectified lumpy DC voltage that is limited in terms of current by the transformer design (usually 1-2 amps max for powersport devices). There is no circuitry to set a maximum maintenance voltage and leaving it connected for an extended period of time WILL eventually cook the battery. A battery tender or maintainer charges at a low current but stops and holds it at the "float" voltage indefinitely to keep the battery at close to 100% of full charge. Unlike lithium batteries, AGM lead chemistry batteries "like" to be fully charged all the time (and don't "like" to be discharged below 30% or so). Unlike some other battery chemistries, AGM batteries don't "like" to be cycled.

Some maintainers are temperature compensated and others are not. This is really only an issue if the ambient temperature is much higher or lower than "normal". The ideal "float" (maintenance) voltage for a battery varies as a function of temperature. Higher voltage required at low temperatures and the reverse for high temperatures. In very cold conditions, an uncompensated maintainer will "float" at lower than optimum voltage which may result in a battery that is not kept at full charge. On the other end of the scale, the device could damage a battery by maintaining too high a voltage. (i.e. Battery Tender Plus has temperature compensation and BT Junior does not.)

TEMPERATURE COMPENSATION (BT PLUS Only): The output voltage is compensated at -3.5mV/ °C/Cell. This increases the output voltage in cold climates to keep the battery from being undercharged and, more importantly, reduces the voltage in high temperature climates to protect the battery from overcharge.

So, if you do the math, a 30°C change in temperature (54 °F) changes the output "float" voltage by a very significant 630 millivolts. Certainly possible in unheated spaces in northern regions (if you consider 20°C/68°F as normal). Pretty extreme on the other end although possible in an unventilated shed. (Even a few hundred mV too high may cause substantial harm over time.)

A 3-4 amp battery tender on my wife's convertible (expensive battery and a lot of electronics that seem to always be drawing power).
I certainly understand that! Thankfully, the "ignition-off" parasitic draw for the FJR is VERY low under normal circumstances. Worth checking with a decent ammeter (placed in-line, key off) if your battery loses significant charge (or goes flat) with a week or two of idle time. If the issue is not with the bike's wiring (or accessories) as evidenced by a measured parasitic draw much over a milliamp or so, your battery may be on its way out due to a "soft" internal short causing self-discharge.
mcatrophy did some measurements on his 2014 and found parasitic draw on the order of 10 µA (micro amps)!! Yours might vary by model year, accessories and accumulation of semi-conductive salt deposits or "dirt".
https://www.fjrforum.com/threads/fjr-ignition-current-draw.160097/
 
Battery Tender isn't everything. It is, however, important that you don't over-charge or run the battery flat. You should also avoid charging at an excessive current (less than 1.5 amps is best - C/10 where C is the capacity in ampere-hours). If you leave the ignition on and flatten the battery, the worst thing you can do is jump start it and go for a ride. Not only did you run it way down but the bike will dump charge back into the battery at far higher than the ideal rate. (But sometimes you don't have a choice - I have certainly done it.) AGM batteries are more tolerant of cooler climates than hot climates - owners in the South replace batteries more often than Northerners do. Note: I have seen a few batteries that were killed by battery maintainers that failed to go into "float" mode when the battery was fully charged or "float" was at too high a voltage. (I have also seen people use a "trickle" charger as a maintainer and absolutely destroyed their battery in less than a few weeks.)

I have NEVER used a battery maintainer on a motorcycle battery. I ride from late March to early December and the bike lives in an unheated garage. I usually leave the battery connected (FJR has a very low parasitic draw) and an AGM battery in good condition only loses a few percent of its charge per month (if not connected). I do give it a top-up with a slow (1 amp) charger for a few hours a couple of times in the off season.

My 2007 got 10 years and 165,000 miles before I changed it - reserve capacity was down but it still worked. The battery in my 2011 is still the OEM after 11+ years (but only 100,000 miles). It has been inadvertently fully discharged a few times and the original owner (who put just 36,000 miles on it) let it sit for almost two years. (Battery is a bit "tired" and will likely get changed next season - but I said that last year too.)
I am by no means an authority on batteries of any type but I can report I had a 2007 with original battery and sold the bike in January 2014. The original battery was still going strong. My current 2014 battery was replaced in May because the dealer said it was weak and since I was about to embark on a 3000 mile ride through Nevada, Arizona, N. Mexico, Colorado, and Utah I thought it wise to replace the battery. For the past 22 years I have kept my motorcycles on a Battery Tender Junior. Over that period I bought two batteries, the first was for a 1995 Yamaha Virago 1100 that had sat for three years. The second was the current FJR after about 8 years.
 
I am by no means an authority on batteries of any type but I can report I had a 2007 with original battery and sold the bike in January 2014. The original battery was still going strong. My current 2014 battery was replaced in May because the dealer said it was weak and since I was about to embark on a 3000 mile ride through Nevada, Arizona, N. Mexico, Colorado, and Utah I thought it wise to replace the battery. For the past 22 years I have kept my motorcycles on a Battery Tender Junior. Over that period I bought two batteries, the first was for a 1995 Yamaha Virago 1100 that had sat for three years. The second was the current FJR after about 8 years.

Yeah. I've found that batteries last longer in milder climates, too.
 
On my 2004 bandit 1200 my battery was the factory original after 10 years before I needed to replace it twice in a 6-month period with no electrical issues just the batteries were crap my FJR I replaced it within the ownership of a month it was a 2010 and then lost two batteries within 6 months one had a cracked post 20 days out of warranty AutoZone replaced it anyway and then I still had troubles with that one so said the hell with it and bought a Lithium-.. and that cranks my bike over twice as fast as the other ones did and I don't foresee any problems as I live in the Seattle area and we don't tend to have extreme Winters there are no sub zero temperatures around here
 
I rode this last weekend with a bunch of FJRs @ a COG Rally in WI. We started @ 33' and snow, came home 3 days later (after 1000 miles) @ 45' and some sun. Everyone was running electric gear and some have heated grips too.

My buddy found his battery dead on Saturday morning ... due to cold or just run down. We jumped it and it lasted the rest of the weekend on it's own.

I found out later it's the original battery in his 2005 FJR!!! I'd say he got his money out of that one. YMMV
 
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