With 27 Watt gloves you should be OK - as others mentioned, just don't spend alot of time idling or low <3K RPM engine speeds if you can help it, and plug in the battery tender when you're back home and you should be fine. Folks usually get into trouble when the plug in 100+ Watts of heated clothing and other accessories, and just make short, low speed trips around town and don't use a battery tender when back @ the garage.