Check out the chart below as a handy guide to battery condition. Take readings at the battery terminals. Be sure to let the battery set for >2hrs before taking measurements. Note, our 950/990's OEM Yuasa is a "Sealed VRLA".
Also, be aware that ambient temperatures over 130 deg F (54 Deg C) quickly kill lead acid batteries.
Here are links to some excellent info on batteries:
YUASA Battery Technical Manual and Yuasa Applications.
Also check out:
Another Battery FAQ
Finally, Understanding Electricity
OEM 950/990 AGM Battery
cyborg: Lightweight Lithium Ion Phosphate 950/990 replacement battery:
AdvRider Forum Post: Shorai battery for KTM 950/990
KOTH: Here is a chart of several replacement batteries compared to the OEM:
** NOTE ** The Braille Battery has had several Bad reviews from Inmates
* Note: LiFePo4 batteries have noticeably reduced current flow at sub freezing temperatures. Therefore, the CCA specs stated above are not realized until the battery has warmed itself up. The manufacturer suggests turning on the ignition and lights for 4-5 minutes before starting at or below 0 deg F.
** Note: Cylindric design LiFePo4 Batteries have lower amp/hours ratings than the other batteries in this table. Therefore "may" not be suitable for use where loads sometimes exceed alternator output more than for a few minutes at a time, or where there is a discharge on the battery when the engine is not running.
Shorai Lithium Ion Battery Charge Table:
For an ongoing discussion of alternate batteries go to this thread on ADVRider.com:
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