The sad truth is that some motorcycles go through extended periods of not being ridden. While some riders are lucky enough to own multiple motorcycles, Winter storage is the most common reason for parking our beloved motorcycles. When smart chargers first hit the market, they were a revelation. Prior to that, people rigged up all kinds of Rube Goldberg contraptions to make sure that their stored motorcycle battery kept a charge but wasn’t ruined by the constant input of the old, dumb chargers. (I know of people who rigged their chargers to stay on as long as their garage door was open so that their battery would get a little tickle of electricity a couple times a day.) Smart chargers that could sense a battery’s level of fitness and switch to a maintenance charge when the voltage was above a certain level are relatively common now, but they were a game-changer when they were first released. Today, in this more mature market, buyers are looking for features to differentiate the available chargers. This is where the Bosch SmartCharge Plus enters the field.

If you need to connect the Bosch SmartCharge Plus with something other than one of these adapters, your needs are pretty esoteric.

The Bosch SmartCharge Plus comes with a full accessory complement to suit most needs, including fully-insulated and removable clamps, quick-connect harness with battery-mounting rings, cable fuse, mounting hooks, and an SAE adapter. Since I’ve been using a different intelligent charger for years, having access to an SAE adapter made the SmartCharger Plus fit right in with my charging set up. The charger also has a handy hook for hanging the unit and keeping it from getting under foot. I used the seat strap as a convenient mounting point.

The SmartCharge Plus has four different charging modes. Mode 1 is for 6V batteries. Mode 2 (the mode primarily used for motorcycles) is for 12V batteries with a capacity of less than 14 Ah and charges using 0.8 A to protect the battery. Mode 3 (what would normally be used for car batteries) covers 12V batteries with more than 14 Ah capacity that can accept a 3.8 A charge. Mode 4 is for larger than 14 Ah batteries that are being charged in a cold location.

All the SmartCharge Plus’ features in one place: the convenient hook, the voltmeter, the LED status lights (voltage, mode, and battery charge state), and the comforting green pulsing light around the Mode button to let you know your battery is being looked after for the long term.

Since overcharging is as much of a threat to battery health as months of neglect, Bosch SmartChargers self-monitor to provide protection from sparks, overheating, reverse polarity and overcharging. When initially connected to a battery, it determines the battery’s condition and automatically sets either trickle or pulse (for deeply discharged batteries with a voltage between 8V and 10.5V) modes. As the charging progresses, the unit’s algorithm adjusts to the battery’s needs. Once the battery reaches 10.5V (or if it starts above that threshold), the SmartCharge uses the trickle mode to safely charge the battery. After the charge is complete, the SmartCharger switches to standby mode, where it monitors the battery’s voltage and switches back to trickle mode when necessary.

The SmartCharge Plus works great at maintaining my personal bike’s battery while I spend most of my time riding test bikes. I wouldn’t expect any less from a quality manufacturer like Bosch. What sets the SmartCharge Plus apart from my previous intelligent chargers, though, is the digital voltage display. When the SmartCharge Plus is connected to a battery, it immediately shows the battery’s voltage – a feature my neighbor appreciated when we used the Plus on his car that wouldn’t start. After a night of charging with little improvement of the battery’s voltage, we were able to determine that his battery needed replacement.

The Bosch SmartCharge Basic offers plug-and-play simplicity. Just select one of the two modes (which mirror Modes 3 and 4 of the Plus) and hook it up to your bike with the same selection of adapters as the Plus – all for $39.99.

My time with the Bosch SmartCharge Plus has shown it to be a versatile tool for assessing the state of a battery and maintaining a battery on an unridden motorcycle. The $49.99 retail price places it in the same neighborhood as other smart chargers, and I feel that the digital voltmeter is well worth the slight premium you pay for it over its more established competitors. Also, I find it pleasant to walk into my garage and be greeted by a pulsing green light telling me my R6’s battery is well cared for.

  • Old MOron

    So Evans, is the Smart Charge Basic not a good idea for motorcycles?
    The text notes that the Basic’s two modes correspond to modes three and four of the Plus. But it’s the Plus’s mode 2 that you recommend for motorcycles.

    • Evans Brasfield

      I was concerned about the very same thing (and almost didn’t include it in the review), but Bosch told me that the Basic will automatically adjust to the needs of the individual battery. So, there is no danger of it over charging it.

    • azicat

      I frequently do top-up charges of my Holden (Chevy) Cruze Diesel using an Optimate 4. That puts out a maximum 0.8A. Works perfectly well; just takes longer.

  • hipsabad

    Works with lithium batteries?

  • michael32853hutson@yahoo.com

    looks small for a real charge on a car battery

    • azicat

      I use my motorcycle’s Optimate 4 on the car for winter top-ups. It has 0.8A output. Works fine, just takes longer than usual.

      • michael32853hutson@yahoo.com

        i once had a small solar charger of the type you put on your dash that could keep a car battery charged- i guess it would work well on a bike too(gave it to a buddy of mine,but i can get another for $20)