| [quote]Originally posted by moto748
but nothing you've said there precludes me from fitting the 16Ah battery to my 2001 bike, does it?
No, the YB16AL-A2 is an excellent battery. Batteries are rated and compared using their amp-hour (AH) and their cold-cranking amps (CCA) capacity. The higher the AH rating and the CCA rating, the better. The only real downside in selecting a bigger battery is weight. The higher capacity batteries are proportionally heavier.
The AH rating is a measure of reserve capacity. A 16AH-rated battery can produce one amp of current flow for 16 hours, or two amps for eight hours, or 16 amps for one hour, etc. A 10AH-rated battery can only supply about 60% of that. So if you let your bike sit for a month without being on a trickle-charger you'll have a (10-15% less each month) reduced reserve for starting because any battery will self-discharge. Once the bike is started, if you don't ride long enough to fully recharge, you'll be down on CCA's the next time you try to restart.
A 200 CCA-rated battery by definition can supply 200 amps for 30 seconds at 0ºF. We usually don't start our bikes at such low temperatures, but the rating is still informative because it gives a measure of the battery's capability to supply the high current needed to turn-over the engine in less-than-ideal conditions. For example, a fully-charged battery at 80ºF can supply only about 60% of the CCA-rating when the temperatures drop to 32ºF. Further, the CCA-rating of a battery drops as it ages, until it can no longer supply an adequate current to spin the starter fast enough to start the motor. That's when you need a new battery. That's also why the higher the CCA rating, the longer the battery can be expected to last.
As an alternative to a lead-acid battery, there are a couple of maintenance-free batteries worth mentioning because they exceed the AH and CCA capacity of the Yuasa YB16AL-A2 standard battery.
Fiamm-GS F19-12B (19 AH, 200 CCA)
Odyssey PC680MJ (19 AH, 280 CCA, 14.7 lbs.) - dry cell technology, my personal choice.
On the track, weight reduction is more important than these other considerations so the weight-saving battery-of-choice is the sealed and non-spillable AGM maintenance-free Yuasa YTZ7S. It's the same size as the later-year stock battery.
Yuasa YTZ7S (6 AH, 130 CCA, 4.6 lbs.)  |