Best battery for a '75 Mark 3?

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My battery (Champion) is old and tired, time for a replacement.

Anybody got a suggestion - brand, model, supplier?

Appreciate it.

Keith Kelly (Encinitas, CA)
 

Ron L

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If you have replaced the cables with larger diameter and have a good starter motor, then the biggest (CCA) battery you can fit into the battery box. :wink:

I have replaced my battery box with an earlier one so I can fit a larger battery (Y50-N18L-A).
 
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I have fitted an "absorbed glass mat technology" after advice given to me by L.A.B. It is a Westco YB14L-A2 (12v14L-B). This fits the MK3 tray nicely.

Not only is there no vent for the acid vapour to spill out of as it is sealed and has no liquid, the battery performance according to specification blurb is superior to lead acid and Gel batteries, and although I cannot directly compare it, it certainly spins up my motor beautifully. 8)

As far as I recall, it allegedly has a much slower self discharge rate than lead acid batteries, and gives a higher cold cranking amp.

The only downside is it is a bit more expensive. :?
 
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I concur with the AGM battery. I've used one for four years. It holds a charge well during periods of non-use and can't leak.
 

L.A.B.

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The Odyssey range of AGM batteries are another alternative: http://www.odysseybatteries.com/

I had an Odyssey PC545 fitted on my Mk 3 for a while, (until I transferred it to another bike, I have a Westco fitted now) although the PC545 battery has to be stood on end to allow it to fit the Mk 3 battery tray, as it's AGM type, the battery can be used any way up (but upside-down isn't recommended).

Best battery for a '75 Mark 3?
 
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Odyssey PC545 in a Commando

do you need terminal adapters? Or do the stock cables fit?

What about a charger for this battery - I've read that a traditional charger doesn't quite do the job. (Also that these things will hold a charge forever, so maybe that's a moot point?)

Keith
 

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Re: Odyssey PC545 in a Commando

pkeithkelly said:
do you need terminal adapters? Or do the stock cables fit?

What about a charger for this battery - I've read that a traditional charger doesn't quite do the job. (Also that these things will hold a charge forever, so maybe that's a moot point?)

Keith

I didn't need terminal adaptors to use either battery, although you may have to bend the wire terminals slightly to get a snug fit on the Odyssey? The Westco has the normal terminals you find on many motorcycle batteries (vertical bolt with a captive nut). I also have heavy duty battery starter wires fitted.

If there is no current drain on an AGM battery (best to disconnect for storage) then they do seem to hold a charge for months, so no need to keep trickle charging them over a (winter?) storage period, and it doesn't do the battery any harm as it would with a conventional lead-acid type, apparently.
 
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