This is all very interesting.
I, for one used flooded cells in about everything, the problem with a flooded cell battery is that the longer it sits on the shelf in the store, the older it becomes, that is, unless it's dry charged with the acid separate which seems to be the case in bike batteries. The exception to that would be an AGM battery like an Optima or a Gel Cell like a Hawker Oddessy.
Most larger batteries, like car batteries and even smaller batteries like in your riding lawn mower are pre-filled and once they are filled with acid, the plates begin to degrade or sulfate if you will. When you buy one, you assume it's new. It isn't. It might have been filled 6 months prior to you purchasing it and it's sat 6 months on the shelf, quietly sulfating itself toward death like a time bomb. AGM as well as Gel Cell batteries sulfate too and they are factory filled so who knows how long they were filled before you bought it?
I haven't had good luck with Optima though I do know of folks who think they are the cat's meow. 2 years agoI traded out my flooded cell, deep cycle battery in the RV for an Optima Blue Top deep cycle and twice the cost of an Interstate flooded cell and it lasted 2 years and it won't accept a charge now. In general, Optima and Hawkers are at least 50% higher in price of an equivalent flooded cell, so for most purposes I'll use the good old standby flooded cell for the auto's, farm tractors and gas powered stuff around the farm.
I have a Hawker Oddessy in the Bonnie. It's sealed though I do believe it has a one way valve to allow gas to escape. All batteries will gas off somewhat and it does have to go somewhere and so far, it's worked flawlessly for 3 years. I went with the Hawker because in the event of a tip over, the acid won't spill not that I could tip it over with the sidecar attached all the time. I also suspect that when the battery in the R3 becomes borderline, it will also be replaced with a Hawker.
One nice thing about a flooded cell battery is that you can pulse charge it and literally shake off the accumulated deposits from the plates, it's those deposits that eventually either short the battery internally or won't allow it to accept a charge but even a pulsed charged flooded cell battery will succumb sooner (it seems in my case) or later.
The best rules of thumb are:
Buy you batteries from a source that has a high turnover rate to insure yourself of a relatively freshly filled flooded cell battery. Stores like AutoZone and Murrays have a large turnover so you should get a freshly filled battery. So does Sears Automotive You don't want to buy a battery, especially a pre-charged battery from you local auto parts store or from a box store like Lowes. They may have been sitting for who knows how long. Batteries are like eggs. The fresher the better
Don't pay too much mind to the date code on top. Most stores do the code when the sell the battery. It may be sitting for a prolonged time on the shelf before you bought it. I've seen retailers who never even activate the date code.
Try to purchase a dry charged battery for your bike. The battery is new until you add electrolyte.
On AGM or Gel Cell batteries, try to purchase them from the manufacturer or a retailer who has a large turnover. AGM and Gel Cell batteries begin to sulfate right from the factory, albeit slower than flooded cell types.
Be espically aware of batteries with dust on the top. They have been sitting for a while, sulfating away, waiting for you to buy them so they can fail sooner than later.