Speed’s Spotlight | Charged Up!

Just having enough battery juice to start a bike isn’t enough. Today’s motorcycles have pretty sophisticated electrical systems on board, all demanding more from that battery than ever before. More than just being able to start a motorcycle and turn on its lights, a strong battery and a reliable charging system to keep it that way is essential to the performance of the entire engine management system. All those computer-controlled sensors and switches need peak voltage to operate as they’re designed to. Even a slightly weak battery can lead to all sorts of problems.

“Hitting the starter button and getting nothing, or that dreaded ‘click, click’ is easy enough to diagnose,” Jason Hanson says, stating the obvious. Jason and the guys at Speed’s Performance Plus see plenty of that as they bring their mobile speed shop/garage out on the road to events all across the country. Everybody’s encountered a flat battery at one time or another, even at an event. That’s why the guys at Speed’s keep a good supply of high-powered Interstate batteries on hand. But a battery doesn’t have to be flat-dead to cause problems, Jason goes on, and the guys at SPP see plenty of that, too. Hard starting, and we’re not talking about just slow cranking, intermittent misfires, rough running, surging, erratic idling and a host of other maladies can all be traced to a weak battery. That’s especially true on late-model EFI bikes relying on those electronically sensitive switches and sensors controlling engine management, sensors and switches calibrated down to the milliamp. “And the current trend toward adding lots of high-powered, and power-sucking, stereo systems along with extra lights everywhere doesn’t help the situation any,” Jason adds. Indeed, the between-the-lines advertising for some of those ear-splitting amps, radios and accessories hints “Our system won’t fry your Harley’s alternator!” That’s comforting. The bottom line is that a Harley needs a strong battery, especially true with late-model EFI bikes set up with lots of add-on electrical accessories, the stereos, amps, lights, communication systems, you name it.

Asking any bike’s alternator to keep up with all that is asking a lot, even during the height of the riding season. The best factory and aftermarket alternators will only bring a battery up to about 80-percent of its full-charge capability, and that’s with everyday riding. Let that bike sit for a week and you can almost be guaranteed a weak battery sooner rather than later. The answer here, and something the guys at Speed’s along with just about everyone else in the know agrees with, is to start with a top-quality AGM (Absorption Glass Mat) battery properly sized to the application and then keep it at peak charge with the religious use of a battery charger/battery maintenance device, something like a Battery Tender. Not to be confused with an ordinary trickle charger, these charging/maintenance units bring a battery up to that 100-percent charge and then automatically switch into a “float” mode to maintain that full charge without any battery overheating, out-gassing or bubbling over. Getting into the habit of always plugging in is easy. Quick connects make motorcycle battery maintenance as easy as charging a cell phone, iPod, laptop or cam-corder. And as an added benefit, besides assuring a strong 100-percent charged battery at all times keeping that battery at its top charge significantly increases its service life. By two, three, even four times.

Out on the road, of course, you’ve got to rely on the bike’s charging system to keep that battery up to snuff. Harley-Davidson’s made some significant improvements in this area, going back to the 2008 models. Addressing all those EFI and accessory-load concerns they’ve increased the amperage and the reliability of the stator, rotor and regulator. The very latest FLH/FLTs, bikes most likely to get loaded down electrically with any number of add-on accessories, even offer a smooth-charging 3-phase system with a whopping 50-amp rating. There are high-output factory retro-fit charging systems available, too. The aftermarket, of course, has plenty of performance charging equipment available, as well, with Cycle Electric and CompuFire, to name just two, offering a broad selection of systems. Is an upgrade system warranted here? If you’re dealing with an earlier bike with a 22- or even 32-amp factory charging system and you’ve added lights, amps or whatever and you’re having performance problems, you bet. Take a close look at that battery and its charging system.

Some problems are easy to spot, some aren’t. Performance problems stemming from the battery/charging system often fall into that second category. Next time the Speed’s Performance team is at a nearby event have them take at look at just how “charged up” your Harley really is. The answer might surprise you.


Speed’s Performance Plus**
(605) 695-1401 – MN
(605) 695-2272 – SD

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