BMW R1200R R1150R/T F800 K1200R R1100R/T R1250R RnineT Message Board

My bike has a BMW/Exide battery, now four years old. The bike starts briskly. The battery connections are tight and clean.

The last few days, the LAMP warning has appeared at idle even after the bike has been ridden enough after startup to ensure the battery's fully recharged; I haven't seen that behavior before. This afternoon, I plugged in the BMW charger for the first time. The charger has now been displaying the amber LED, marked "2/3," for about six hours. That seems like a long time. I'll leave it plugged in overnight.

Given the BMW/Exide battery's reputation and age, and my desire to not have a mid-trip surprise, it seems the reasonable course here is to replace it. Anyone disagree?

Did you turn on the key when you connected the charger to the socket? If I recall correctly, the BMW charger requires the bike's can-bus system and the charger to "hand shake" when first connected. After a few seconds the Key can be turned off. If not turned on the charger may not charge or correctly indicate charge status.

That said, 4 years is not bad. My first battery went out much earlier. Would not hurt to change or get a set of jumper cables.

Mark_1

I guess I dont know what BMW's battery's "reputation" is, but 4 years for a battery of that size even properly maintained is a usefull life span. I agree, I dont see replacement as a bad idea.

Dbrick - after ALL the threads about batteries and the general consensus that 4/5 years is a good life span for the original battery I would imagine the only question would be what brand would you replace it with. But that would cause another 'my battery is the best thread'.

The lamp led coming on at idle and then going off is weird,but I'll admit to not reading the entire owners manual.

dbrick wrote:Given the BMW/Exide battery's reputation and age, and my desire to not have a mid-trip surprise, it seems the reasonable course here is to replace it. Anyone disagree?

I would replace it. I was at around 3.5 years when the boot up dance failed. The second time I caught a glimpse of the dreaded EWS. Then one morning the bike wouldn't start. Not even a click. When the BMW/Exides go, they really go. Four years is a good run.

Thanks, all.

Mark_1, I did turn on the ignition before plugging in the charger, and left it on a few moments after things were connected yesterday afternoon. The charger started with the "1/3" LED on, and after an hour or so went to "2/3." This morning, the "2/3" LED is still on.

Newportcycle, the BMW/Exide AGM batteries seem to fail suddenly, without much warning, and not last much beyond 4 or 5 years. Mine isn't a sudden failure - when I rode it yesterday, the bike still started briskly - but I surely don't want a surprise.

Harry, the LAMP warning appears at the bottom of page 26 of the Riders Manual. It displays in place of the odometer, and the Riders Manual says it appears if there is a defective bulb . However, all the light functions (and thus, I assume, the bulbs) on my bike work all the time. I've seen the LAMP warning only at idle and only shortly after startup: not immediately after startup (when the idle is a bit higher, thus allowing the alternator to contribute more to system voltage), not a long time after startup (when the alternator has run enough to recharge the battery), but in the middle time period, perhaps 3 -8 minutes after start. Because it appears in so specific a situation, I assume LAMP actually indicates (or also indicates) a slightly low system voltage, reflecting battery inability to maintain a charge.

Bill, the boot dance failed only once, two years ago, when I inadvertently left the ignition on and completely flattened the battery. The bike started easily with a jump. The next leg was almost a hundred miles and I didn't stop. The day after, I started the motor twice in going out for gas, and the bike behaved normally. I wondered at the time if this episode damaged the battery, but it has been symptomless up until the last few days.

I'll order a battery now. I had great service from Odysseys in my Oilhead, but this time I'm going to try a Yuasa YTX14H-BS.

3 to 4 years is about it for a battery. What bothers me is the warning light at idle. You need to check the voltage at idle and rev'ed up a bit. IT should be 13.5 or better if your alternator is good. A really bad battery can pull it down at idle, but not likely if it will start the bike.

Thanks, Scott, I'll put the meter on it and see what's up.

I don't think it's a really bad battery; as you observe, it starts the bike right up. I think it's a sorta bad battery: good enough for this warm-weather cranking, but impaired in terms of ultimate capacity.

Have you considered the new Shorai? http://www.shoraipower.com/c.3379047/Ba ... finder.ssp
With Santa Cruz's temperate climate, you'd easily get four years out of it — and likely a lot more. Have not tried it, but if it's battery longevity you're after, this is probably among the best.

The Shorai wasn't convincing for me. I'm not an early adopter, the weight saving isn't significant for me, and my use is such that batteries usually last quite a while. I'm content to go conventional AGM, and the Yuasa turns out to be quite inexpensive to boot - I found it new on eBay for $62 delivered.

The Yuasa battery is a good choice. I installed one in place of the BMW/Exide in my '07 (showed 3/3 on the BMW charger and still wouldn't start), and none of the electrical gremlins have re-appeared.

Thanks, Ken. That's reassuring!

The Yuasa hasn't shown up yet.

However, the BMW/Exide apparently learned about the order: since I originally wrote,
the LAMP signal has been completely absent. <g>