Deltran Battery Tender Lifespan

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To start like a dog (or even not start) one time and then start right up the next (after a short wait) doesn't sound like battery to me! A battery can "recover" by waiting (to some extent) after a heavy drain (like leaving lights on) but that does not describe this circumstance.

By bet is on the starter! Possibly the contacts on the starter relay are going south instead but I think this is the direction you should look.

Best way to diagnose whether the starter is going bad is to check the cranking amps using a DC clamp-on ammeter. Of course, you need to make sure that the battery is OK. If you do not have an on-board voltmeter, pull the battery, charge it fully using a trickle charger and get it load-tested.

Note: You can check the battery tender function with a voltmeter. Assuming you are running at near room temperature, the float (maintenance) voltage should be around 13.6, if I remember correctly.

 
I read on the instructions of one of the replacment batteries I installed that they should only be charged to a specific voltage,and not left to float for long periods. Was this a dream old farts have from time to time?

 
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IF the battery tender is temperature compensated and IF it is working correctly, it shouldn't hurt the battery to leave it on a float (not trickle) charge indefinitely. That said, there is no need to leave it on a tender. Self-discharge rate and parasitic current draw on the FJR are low enough that a "top-up" every month or so is sufficient (as long as the battery and bike are working properly). In a 3-4 month winter layoff, I top-up my battery maybe twice. The bike is a 2007 FJR with 147,000 miles and still has the original battery. Bike is winter-stored in a heated space. (Will likely replace the battery next season - it is noticeably weaker; but I said that last year too.)

Note: A lot of battery tenders are NOT temperature-compensated and/or to not accurately regulate the float voltage. If the float is too high by even a couple tenths of a volt, you will eventually cook the battery.

 
I've got two of the old 1.25 amp Battery Tenders that I've had for 15 or 16 years, and they're still going strong. I don't use them full time, though. If I know I'm not going to ride either bike for a couple of weeks, I'll plug it in, but if I'm riding fairly regularly I don't worry about it.

I also have a Battery Tender Junior that I keep on my lawn tractor virtually full time, and it's probably 7 or 8 years old.

 
I disconnected the tender after an all night top off. I left it alone for a few hours then started it up. It started right up super strong. I put a meter on the battery and it showed 13.75v and it dropped to 10v at start up. That looks good. I'll keep an eye on how it behaves. I'll keep you posted.

 
My original Battery Tender is probably about 18 years old now and working fine. Won a Battery Tender Jr. as a door prize about 4 years back and it works well also. 5 bikes in our garage I just rotate which one is on tender every week or so in the off season.

 
I have had two Battery Tender Jrs fail. Both of them lasted about two years before failing. I have three more in use today.

When the first failed, the light would just flicker when I plugged it into the wall. Tried it on several different batteries.

When the second failed, it would not turn on anymore at all.

 
Thanks for all the replies. I charged the battery last week and all seems to be good nowwith the battery and tender. Can't imagine what happened a while back on my OP. Let's see if that continues.

 
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I've had a BT Jr. for 8 years, still going, but, remember it doesn't have the guts to charge a dead battery... best use it for maintenance on a reasonably charged battery. I have three of the "good" BT's and they all work fine after 3 or 4 years.

 
Yikes! Almost the exact same situation here at my house.

I got my first Battery Tender in '96 for my wife's then new EX-500 then a second in '97 for a then new GSXR 600. So, that's about 18/19 years each and I'm still using both tenders with no issues. They've outlasted the bikes.

I too, also have a couple BT Juniors I rotate around for daily maintenance to help keep up on current 5 bike fleet. Funny how many of us have similar stories.....

 
I've had the Deltran BT Jr. model for about 10 years, and I use it regularly on my riding lawn mower. I sometimes move it to a bike if the mower is OK and the bikes needs it. These were recommended to me first by a BMW Parts Department Manager who thought that the BMW charger was way over priced.

I've also got one of the Deltran multi-station units... I think it's 4 stations, but it might be five.

That one is probably 8 or more years old, and it has never hiccuped either.

I've also got one of those fancy Triumph badged Optimates of some flavor. Maybe 3+ or something. I've had that one for about five years. It has also been trouble free.

 
I've had really mixed results with Battery Tenders. Weirdly, or ironically, I've had far more success with the Sears house brand of BTs.

The first few Battery Tenders with the old metal case kept boiling out my batteries on my bikes and my generator. I had to replace too many batteries! The Sears Craftsmen ones I replaced them with eventually failed after a few years but never damaged a battery or boiled it. My last one is still running and I switch from the FJR to the generator every few weeks.

However, I have a couple of the weatherproof models of Battery Tenders and I have had GREAT luck with them! One has be going for nearly 3 years on my FZ1.

I have NO idea why some people have/had such good luck with the older BTs and I had nothing but trouble.

 
I've got one old-style that's 20+ years old, a newer one that's at least 11 years old, and a BMW one that's about 9, I think. My neighbor has my other old-style, and if he hasn't dropped it into the lake, it's also ≈20.

 
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