Battery Tender

The FJR manual states that their "Valve Regulated Lead Acid" battery needs a "speical" constant voltage battery charger. I have a Battery Tender Junior. Will this be compatable with the FJR's battery?

I ask because this Battery Tender Jr manual states that it has 3 primary charging modes. The final mode "storage/float maintneance" is a constant voltage mode. But the 1st and 2nd modes are constant current and high constant voltage/decreasing current.

Thanks

https://goo.gl/photos/3HFkeBAMABD6C6vq5

No problem with the Battery Tender.

VRLA is a generic term for any sealed, no maintenance battery. The battery in your FJR is of the AGM (Absorbed Glass Mat) type of VRLA Battery. You therefore want a battery charger that is recommended for AGM lead acid batteries. The Deltran Battery Tender Jr is recommended for AGMs, so it should be fine.

Personally, I do not like to leave my battery on any tender continuously for the entire off season (Queue the southerners' jokes about "what offseason?"). I have two bikes and alternate which one is on the one tender every week or two (I have an Optimate 3, which is also a good AGM trickle charger). Cold weather actually slows the internal discharge of a lead acid battery, so even a 50% duty cycle of charging that I use is overkill, IMO.

The Tender Jr is compatible and can be used as a float/maintenance charger. It is a bit under size for trickle charging an OEM size battery, ideally, a trickle charger for the OEM 12 amp/hr battery should be 1.2 amps. Just to be sure, let me say that a float/maintenance charger is just maintaining a battery which is already at a full charge; a charger brings a depleted battery back to a full charge. If you are using the Tender Jr just as a maintenance device it's just fine.

Edit: I see that others addressed the issue while I was typing.

Not to be contrarian, but I don't think you'd have any big problems with charging a depleted FJR battery at 750ma vs. the recommended 10% of battery amp hour rating (1.2 amps). I think it would just take a lot longer. I've always taken the the 1.2 Amp figure to be a maximum charge rate, so as to avoid overheating and damage to the plates.

Thank you all for the clear and consise answers. This is a great place to get technical info!

Fred W said:

Not to be contrarian, but I don't think you'd have any big problems with charging a depleted FJR battery at 750ma vs. the recommended 10% of battery amp hour rating (1.2 amps). I think it would just take a lot longer. I've always taken the the 1.2 Amp figure to be a maximum charge rate, so as to avoid overheating and damage to the plates.

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Here I am having to defend my honor on the internet again I said, "It is a bit under size for trickle charging an OEM size battery, ideally, a trickle charger for the OEM 12 amp/hr battery should be 1.2 amps" I didn't say the Tender Jr couldn't/wouldn't charge an OEM battery, as Fred Said, it will just take longer.

JAB said:

Thank you all for the clear and consise answers. This is a great place to get technical info!

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Ask a good question and (usually) you will get a good answer. Look around for previous posts first and then ask a good question you will almost always get a good answer (and then the thread will drift off in several very wrong ways )

I agree with what has been stated relative to AGM batteries and (Deltan) Battery Tender Jr. I have been using them for years on both my FJR's and one of my cars. It does take a longer time to bring the battery up to full charge but not an issue for me. I have had very long battery life with my first FJR(2007) that I had on a tender from new until Jan 2014 when I sold the bike. It had the original battery and never showed any signs of weakness.

Yep, standard trickle charge is 10% of amp/hr rating.

Not like ionbeam needs backup. LOL

Like Fred, I think the 10% is considered a recommended maximum. Less than that will just take longer to backup, but it'll do it ..... eventually

FWIW,. I went on a 10-day bike trip a few years back and had left the dome light on in my pickup. When I got back the battery was so dead I'd lost my radio presets. That's a dead battery! I recharged it with a Battery Tender. It was the 1.2 amp model, but then, the battery was a car battery. It also took a long time -- the better part of two days if I remember correctly. But I used the battery for another couple of years after that.

Don't leave your bike battery on a 1.anything trickle charger for more than a few hours. It will overcharge it and dry it out, reducing the battery's capacity at best.

A true battery tender will detect the battery is fully charged and turn off its current, just keeping the battery topped up as and when required.

Also, don't leave any charger connected to the battery with the mains supply turned off. Some chargers will take a current from the battery that can lead to a deep discharge, from which the battery may never recover.

What unit would you recommend, Mc?

Yuasa also makes a great battery maintainer. I have 3 of them used on my bikes and even a car from time to time. Very good quality and very reliable.

Go to Amazon and search for "yuasa smartshot" .

Highly rated and reasonably priced.

majicmaker said:

What unit would you recommend, Mc?

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There are many that are good, MrZappo's suggestion would certainly be a good choice, designed by Yuasa for their Yamaha OEM batteries.

Oxford do some, as do Deltran. Almost any will do that says it is for a motorcycle battery and that it switches to a maintenance state when it detects the battery is fully charged.

Some have additional features, like saying they can recover a battery from a deep discharge (read that as "might be able to get the battery functioning again"). Another possible "feature" is to periodically discharge the battery then charge it again. (I've never seen any benefit for this on a motorcycle battery.) The more features, the more it will cost, but unless you think you need these extras, there's no need.

More important is ease of connection, lengths of leads, mounting features, weatherproofness if necessary. You would need to attach a connector to the battery to plug the tender in, you can't use the glove-box connector as this is switched off by the ignition switch.

I warn again about leaving a charger connected without the mains supply on. I have seen the effect of a charger connected to my son's bike's battery to maintain it while he took over a year to recover from broken bones (long story). He attached a trickle charger, then put on a mains switched timer so that the mains was on for an hour or so every few weeks. It ruined the battery completely by deep-discharging it with its "leakage" during the off periods.

Caveat: Please note, although I am familiar with electricity and batteries and their characteristics, I've never put a charger on any of my bikes' batteries. All my batteries have lasted the full term of my ownership, up to four years or so, without any signs of problems. I do ride year-round, and here in the UK we don't get the extremes of temperature experienced in the US.

I also had concerns over the VRLA battery statement in the GenIII owner manuals. While VRLA includes AGM and Gel batteries, my research left it unclear whether the older Gens' AGM batteries were actually VRLA, ie, were sealed tight and had a valve. The GenIII batteries apparently do, and require a constant voltage charger. The sealed state will keep vapours in, and the valve will release gases if the internal pressure gets too high. When asked, Deltran said "Our charger will hold your battery at a constant voltage between 13.4-13.8 voltage at about a tenth of an amp. That is the constant voltage". Optimate on the other hand, overtly states theirs are good for VRLA.

It also important that your charger of choice does not have a desulphation mode, which boosts voltage for a period, i.e., it is not a constant voltage charger. Deltran does not have desulphation mode, BTW.

RaYzerman19 said:

I also had concerns over the VRLA battery statement in the GenIII owner manuals. While VRLA includes AGM and Gel batteries, my research left it unclear whether the older Gens' AGM batteries were actually VRLA, ie, were sealed tight and had a valve. The GenIII batteries apparently do, and require a constant voltage charger. The sealed state will keep vapours in, and the valve will release gases if the internal pressure gets too high. When asked, Deltran said "Our charger will hold your battery at a constant voltage between 13.4-13.8 voltage at about a tenth of an amp. That is the constant voltage". Optimate on the other hand, overtly states theirs are good for VRLA.

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The stock 3rd Gen FJR battery is a "Yuasa GS" brand, "GT14B-4" model battery, same as it has been since first release in 2002. This is a VRLA AGM battery. There is nothing new or special about the 3rd Gen battery or its requirements for a maintenance charger.

I don't know where this new "constant voltage" requirement came from (other than they just stuck in the manual), but I serious doubt the need for a truly constant charging voltage.

RaYzerman19 said:

It also important that your charger of choice does not have a desulphation mode, which boosts voltage for a period, i.e., it is not a constant voltage charger. Deltran does not have desulphation mode, BTW.

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The Optimate 3 charger (which I own a copy of), which the manufacturer Optima states is suitable for VRLA AGM battery charging, does have a desulphation mode. That mode is only triggered if the self-test determines that the battery has been deeply discharged and has (possibly) been internally damaged by sulfation of the lead plates. This would be a last ditch attempt to resuscitate an already damaged battery. For normal maintenance trickle charging that desulphation mode is never initiated, so should not pose a problem. My limited experience shows the Optimate charger works fine for maintenance of my FJR and Suzuki Vstrom VRLA AGM batteries.

I also have an Optimate III. Once I wired my GPS through the switched side of my Fuze Block I no longer have had any battery issues. Before I did that I had issues. Tender is wired direct to battery with inline fuse and an SAE plug tucked under the fairing.

mcatrophy said:

Don't leave your bike battery on a 1.anything trickle charger for more than a few hours. It will overcharge it and dry it out, reducing the battery's capacity at best.
A true battery tender will detect the battery is fully charged and turn off its current, just keeping the battery topped up as and when required.

Also, don't leave any charger connected to the battery with the mains supply turned off. Some chargers will take a current from the battery that can lead to a deep discharge, from which the battery may never recover.

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As I found out

in case anyone is looking for a bat tender - Costco $29.99