Alternator or battery?

[WJBertrand]

Both of my experiences were in older vehicles though. The wife's car was a 1990 Plymouth Voyager Minivan and my '83 Interceptor wasn't more than 3-4 years old when it's battery suddenly up and died.

I've actually had better battery life with my newer vehicles. 8+ years for the ST1300 and I went 10 years on my 2002 Lexus IS300. Had to replace the battery in our Toyota Rav 4 after only 3 years but I think when it was in the body shop for a minor repair they left the key on or something. When we went to pick it up the battery was toast. They jump started it and I put it on a charger when we got home, but my experience is that once you heavily discharged a lead-acid cell, their days are numbered. We'll see how long the OEM battery lasts in my Mustang GT, 2 years old so far.

[Critters]

My last battery in my 1300 lasted 8 years which i thought was really good . My current battery was replaced in July 2013 so will see how it goes, if quality is on the slippery slope downhill only time will tell i suppose.


Brian
Ride safe

[alans1100]

I went searching on how to make bike batteries last longer and found this.

Understanding Motorcycle Batteries http://www.yuasabatteries.com/motor_battery.php

Quoted the last sentence "A lot of riders who believe they take excellent care of their batteries are actually killing them with kindness."

On average I ride 6 days a week all year and don't think about doing anything re maintenance for the battery. The Yuasa that I just replaced was in use for no less than 3 years 6 months and no more than 3 years 9 months as I don't recall the exact month in early 2012 that I put it in. The longest time a battery sat for me was from Jan 2012 to end of March while I did the timing belt etc. which more than likely led to putting in the last Yuasa.

Now with an Australian made SSB battery I wonder if it will last as long as the Yuasa ones.

[Uncle Phil]

I gave up the 'new' Yuasas when they started failing at just over a year. None of my bikes seldom sit for over 3 days as I rotate them back and forth to work - unless I'm on a long trip. I've swapped to a MotoBatt AGM batteries in all 3 ST1100s. They are approaching 3 years and still start the bikes fine. I also like the 'extra' set of terminals you can add for hooking up additional connections. That way your 'main' connections stay clear. Of course now that I've said this, all three will probably die tomorrow.

[David W]

... check for possible parasitic drains; [there] may ... be (aftermarket) accessories draining (i.e. active GPS-cradle hooked to battery terminals/permanent hot lead...), or wiring issues/corrosion that "shunt" current from a live wire onto ground/chassis ....

I agree that every rider should know how to check what Honda (at least) calls "leakage current". To check it:

1. Get a digital multi-meter; even a cheap one should work for this. Slide an "alligator" spring clip over the metal tip of each of the two test leads.

2. With the ignition turned off, disconnect one of the battery cables; usually the negative one is the easier. Switch your fused meter to DC amperes.

3. Connect the meter to the end of the loose battery cable and the exposed battery terminal. The reading on the meter is the leakage current. (Do NOT turn on the ignition while doing this.)

If the bike has a clock (which is constantly powered by the battery directly through a fuse), Honda allows up to 3 milli-amperes, or 3 mA.

I personally like to pull the clock's fuse (to eliminate its drain) and verify that the leakage current goes down to more like 3 micro-amperes, or 3 uA or less.

(But if the meter reads dead zero, that zero reading is always suspect: check the connections, and check the meter's fuse. I put the clock fuse back in and remeasure to be sure.)

I think BMW was the first to put clocks on their bikes, so Pieter probably has one on his. The more accessories the bike has, the more important the above test is.

His battery is probably BMW brand and therefore expensive. So it is probably ok although it would be nice to know if it is the AGM (Absorbed Glass Mat), sealed, lead-acid type; is it BMW-recommended? And how old is it?
(Alternators do not fail on Beemers, do they?)

[Pieter Huizinga]

Continuing story: Checked the circuitry today, found nothing wrong. Checked the battery, totally flat. Either the battery is toast, which the Optimate denies, or there is a serious leak of current.

To be continued.

[Uncle Phil]

Pieter - A simple test if you can do it in the 'dark'. Disconnect the positive battery terminal with the key off and see if it 'sparks'. If it does, pretty good indication you've got a battery 'drainer' somewhere.

[oslin2014]

Pieter you should get the headlight bighten when you rev the engine up if it is charging if it is I would go for a battery and then check the charge rate if it happens again i.e. battery gets low
Keith

[Pieter Huizinga]

I don't think I've reported the outcome yet.
Although the battery tested fine with the charger, we replaced it. It worked fine for a few days. Then the bike got a total overhaul. It worked fine for a few days. It kept stalling more and more until I had to walk home. My mechanic put it on BMW diagnosis and everything tested fine except the start relay. So he replaced the start relay. It worked fine for a few days. It involuntarily had to stay in the yard due to frost, snow and more of that shit which I don't particularly like to ride in.

When weather improved and I wanted to use it, it wouldn't start. Back to the drawing board.
I may have bought myself a pig in a poke.

[Andi Archer]

See if you can pick up one of these isolators below Pieter and connect it on the negative battery terminal so you can easily isolater the battery when not in use.Id suggest you have a leak to Earth on the system somewhere that is draining the battery.Do you have an alarm that runs when the bike is stood as it may not be going into standby mode?

http://www.ebay.co.uk/itm/252186337196? ... EBIDX%3AIT

Battery Isolator Switch Power Kill Cut Off On/Off Switch


https://www.youtube.com/watch?v=kxAcF7XcnkI
https://www.youtube.com/watch?v=fhjnDhMR49E