796 starting issues after shorai battery instal

[gitter]

how much bigger was the shorai compared to what? Also, the 18 is now back to reading sub 13s on the bikes display.....am I missing something here? Or should I just go back to the stock one and call it a day?

[1UglyBastard]

i meant price wise, how much was the bigger battery you bought, the 18?

a tech at my local dealer told me that the Duc 999 regulator/rectifier did a better job of charging the Monster battery. I wonder if that's your issue. If it were me, I'd remove the new battery, charge it to its max, read the voltage with a meter, let the battery sit 24 hours, recheck the voltage to see if it dropped. If it dropped then it would be the battery not being able to hold a high charge. if it didn't drop then i'd reconnect it to the bike and let it sit overnight and see if it drained. if it drained, then something on the bike is draining it. if not, then i'd ride the bike for a week or so and check the voltage again. if it dropped then it's not charging to a high enough voltage.

[triangleforge]

Have you given the charging system a thorough check? In an earlier post, it sounded to me like your charging voltage was on the anemic side - as Howie suggested, you might not be hitting full voltage, which would explain why the new battery is behaving the same as the previous one.

I've got a Shorai in the ST2. According to the voltmeter I installed on the dash, it stores at 13.2, pretty much indefinitely (I know that's lower than it should be). Cranking at temps around freezing isn't as enthusiastic as I'd like, but it hasn't ever failed to start - more than I could say with the Odyssey AGM* battery I fought with for over a year.

(*As part of teaching my class some very basic statistics, I've tried to drum into them the vagaries of small sample sizes, so my lousy experience with an AGM battery and generally good experience with a Shorai are exactly that: two anecdotes that may or may not be helpful to your issue.)