I have 2 Tender "Plus'"

 

Battery Tender makes a charger specifically for use with gel batteries. They're sold at BMW dealers. You might find them online, too.

 

Folks are going to argue with me on this one ....
The best and only real way to fully charge a battery is to take it out on the highway for about a half hour or more at least a couple times a month. You get those windings whipping around ... that's the correct way to charge. Some people think that if the trickle charge it or just start it up once in a while that will do it. No way. In fact just idling it will actually drain the battery because all the lights and options are powered.

Run that thing!

 

Thanks! The Harley is a gel but the quad is the battery where you add the acid and seal. I check out the BMW dealer.

 

No argument! My scoot has a voltmeter and sometimes (when snow) I run it at 14 volts for about 10 minutes (1000 RPMS). Otherwise, it falls below 13 or 12 and that doesn't help the batttery at all.

 

I keep my riding lawnmower on a Battery Tender Jr all winter long. It's about 10 years old. Starts up every spring. I keep my 04 Fatboy on a BTJ all the time, summer and winter.

 

Charging an HD battery with a BMW tender? Hmmmmm, I don't know.........

 

I switch my battery tender between my Harley, Triumph and BMW Z3 roadster all winter. Never have a problem starting. Seems to me it's a lot better to keep the batteries charged than letting them run way down and then having to recharge them.

 

The fastest way to kill a battery is to let it go dead and then charge it. When it is dead, it can start to sulfate and you can have a dead cell, even after the first time.

The security system on some of the bikes pulls on the battery. Mine can drop enough to have a hard time starting the bike within a couple of weeks, especially if it's cold.

I have a Craftsman tender that works great, when I remember to plug it in. If I have a couple of weeks when I won't be riding, I plug it in. Same battery since 07 and still running perfectly, at least when it's charged.

 

Battery tenders, maintainers are not harmful as they don't charge at all unless the battery drops below a certain level what it requires charging. They are not per say continually charging like some may think. They are designed for sitting batteries ie motorcycles, riding mowers, boat batteries. They definately don't shorten battery life.