[SV650rules]

Leaving any lead acid battery at a low state of charge is the worst kind of battery abuse -although AGM will tolerate it better - once plates start to sulphate up (plates get coated up with inactive lead sulphate crystals that drastically reduces their capacity) there is no real cure, a battery kept in its top 20% of charge will be a happy battery for many, many years.

http://batteryuniversity.com/learn/a..._to_prevent_it