If you are in the market for a battery tender/charger.....or want an upgrade - I would look at the NOCO line.
These chargers/tenders have far more abilities than most, as they can be set for lead acid, AGM and Lithium battery types. They also can recharge a battery that is down to 1 volt....most smart chargers can't do that. They also have modes to restore/cycle the battery to make it healthier if the battery has been abused.
Most small motorcycle batteries recommend a small charger of 1 - 1.5 amps. This does require a pretty long time to charge a battery that is run down - for a 14amp/hour sized battery in the Savage a full charge from dead would require 14 hours if you used a 1 amp charger. Partially discharged batteries would charge faster. The smaller the amperage of the charger the better it is for use as a "maintainer", as slow charging is the most gentle way to maintain the battery.
https://no.co/genius