Boxerworks.com

I wrote a reply this morning and it must have dissipated into the ozone so I'll try again.

I have Odyssey batteries in my bikes. Three have 925Ls and the Cafe Racer has a 680.

My across the street neighbor had trouble with his battery one day and I took my 680 which is pretty small, to help him jump start his car. He was impressed that it had so much starting power. Voltage, current, I don't know, but it started his car like a champ.

On my R90S I even built up a riveted aluminum battery box for the 925L. I also modified the tool tray so it sits down as it's supposed to. (the battery is a little taller.)

Chuey

Always ran large BMW batteries in the RS and got about 3 years each.
Last time I went to buy a bm battery it was $100 more than previous.
I now have a Motobatt agm in there. 2 years, so far so good.

What a lot of people seem to be unable to understand is that the life of a battery is dependant on a lot of factors, not just the quality of the battery concerned.

One way to look at it is:

You buy your brand new bike... it has a brand new battery, a brand new starter motor, brand new wiring with clean connectors and a brand new alternator with a brand new regulator. you ride it for four years (say) and the battery gives up. Fair enough... thats not a bad life for a battery so you go and buy a similar one. Now the starter is a bit tired, the bike isn't starting quite so well, the connectors are a bit corroded and the regulator isn't working as efficiently as it was. Everythings working OK (ish) but nothing is at it's peak efficiency. The battery only lasts 2 years. So... it's a crap battery thats wrong isn't it!

or

Another way to look at it...

A battery might be considered to be good for a given number of starting cycles. Lets call the number x. Thats not engine strts, thats presses of the starter button so to speak. If the engine starts first press every time, the battery will last a given time... If, on the other hand, the bike needs 2 presses on average to start (or you need to crank the engine twice as long) then it's a reasonable (if very over simplistic) assumption that you'll get throguh the x starting cycles in half the time... which is another way of saying that the battery will only last half as long.

So, what am I trying to say...

Basically, if you buy a series of batteries and they don't seem to last as long as you might reasonably expect, the chances are that the problem is with the bikes electrical system getting tired, and not with the replacement battery.

Rob

Rob I agree

All good points Rob.
When I purchased my RS in the spring of '06, the P.O. said the battery was new.
This summer is the 6th season and it still holds a charge and starts the motor.
It is an OEM BMW wet cell battery.

Although I agree that bikes' electrical systems age and corrode, causing more stress on batteries, I have found that batteries still can last 4-6 years. The Sears and WalMart tractor batteries (U1 style) are basic lead acid but soldier on very well. The almost are garanteed to last 5 years despite abuse. I found one at 1.5 years old half full after a 2000 mile trip. The voltage reg had failed and was overcharging/cooking off the electrolyte. I changed the voltage regulator and topped off the battery with distilled water. Four years later it started giving up the ghost - can you imagine my chagrin!!!! ). Despite the age and moles on my /6 almost every battery has given me 5 yrs ... until the "dreaded WestCo".

I wonder if the real measure of resistance (strength or life) could be in the amperage capacity of the batt? The 32 A tractor batteries are powerful heavy duty things. Moto batteries are lighter. I don't know. I'm a language major, not an engineer.

Teo

To Carry on from Rob's point, I think there might be quite a few bikes that did not need 450w alternators, if their charging system had been working well in the firstplace!

teo wrote:I wonder if the real measure of resistance (strength or life) could be in the amperage capacity of the batt? The 32 A tractor batteries are powerful heavy duty things. Moto batteries are lighter. I don't know. I'm a language major, not an engineer.

Teo

There are other factors, but that's a huge one. When that battery has lost 1/2 its capacity, you still have a 16 AH battery.

CCA is another: how fast the battery is willing to give up its charge. The Odyssey batteries have a very high CCA rating for their AH rating, so they can still provide nice starting even after losing part of their AH capacity. Also, their AH capacity doesn't seem to deteriorate nearly as fast (or, at least, as linearly) as conventional batteries. In my experience, they continue to operate like new for nearly their entire life, and then give up rather suddenly. This is both a blessing and a curse, depending on where in that lifespan you are.

Major Softie wrote:

teo wrote:I wonder if the real measure of resistance (strength or life) could be in the amperage capacity of the batt? The 32 A tractor batteries are powerful heavy duty things. Moto batteries are lighter. I don't know. I'm a language major, not an engineer.

Teo

There are other factors, but that's a huge one. When that battery has lost 1/2 its capacity, you still have a 16 AH battery.

CCA is another: how fast the battery is willing to give up its charge. The Odyssey batteries have a very high CCA rating for their AH rating, so they can still provide nice starting even after losing part of their AH capacity. Also, their AH capacity doesn't seem to deteriorate nearly as fast (or, at least, as linearly) as conventional batteries. In my experience, they continue to operate like new for nearly their entire life, and then give up rather suddenly. This is both a blessing and a curse, depending on where in that lifespan you are.

Agree with the above... but there is one other factor. The PC680 is rated at 18ah whereas the 'standard' boxer battery is rated at 28-30ah. Despite the fact that it has a high CCA rating (and I accept that this means they generally give more Oomph) it is till 'only' 18 ah. In short, this means that, if the bike is a reluctant starter, you are likely to get less attempts. Don't get me wrong, I still like the Odyssey battery and I use it but, if you do have a reluctant starter, or if you do very short journeys with frequent engine starts, it can be a two edged sword and a BIG high ah battery might be more appropriate.

Rob

The Motobatt in my RS is an agm 380 cca, 32ah Made in Jacksonville Fl.

What do youse guys in the states think of 'em?

The Motobatt cost me about $180 AU. A BMW battery was gonna cost me about $260. Up about $100 from the last bm battery. They lost me.

The only problem with the Motobatt is that it's YELLOW!