March 20th, 2013

Who remembers the Trek Lime? Or for that matter the original Autobike (not sure if they’re related)? It seems that the holy grail for bike designers is a bike that appeals to the masses not because it’s the lightest, or fastest – but because it’s the simplest to operate. So, first there was the Autobike (that are going for $799 on ebay!) which was quite the bike. Equipped with centrifugal weights on the rear wheel and a Low-Normal rear derailleur that was attached to said weights, the rider would start pedaling causing the weights to spin outwards which in turn shifted the derailleur to a harder gear. Stop pedaling and come to a stop, the weights would return shifting the bike into an easier gear to get started. Quite the Rube Goldberg contraption, the whole design was actually fairly clever. Too bad it didn’t work. Pedaling at certain cadences would leave it in between gears, the gearing was usually off, and the as-seen-on-tv nature of the thing caused most to be horribly assembled and destroyed on the first ride – at least the only bikes we ever saw in the shop were broken.

Then came the Trek Lime – which was a great bike, though it wasn’t perfect. The Lime did nearly everything right with the exception of the 3 speed internal hub that seemed to turn potential customers off. Apparently not wanting to shift, didn’t necessarily mean they didn’t want gears.

Which is where the new Autobike and NuVinci step in with the first automatic shifting, CVP equipped bike that we know of. Thanks to a 360 percent gear range and smooth, automatic shifting – the new Autobike shows a lot of promise.

Autobike's New Auto Shift Goes Electric, No More Wheel Weights

Just like the Trek Lime which was based on the Shimano Coasting platform, the Autobike has three main components to the automatic shifting puzzle. In order to provide the system with power, the front hub features a SRAM dynamo that provides continuous juice to the system so that the rider never has to plug it in. Wires lead from the front hub, through the frame, to the bottom bracket area where it joins the brains of the system – or the small onboard computer and sensors that detect your speed and cadence. With this info, the computer then tells the shifter mounted on the rear hub how to shift the “gears” and a small motor carries out the shift.

The biggest difference here is obviously the inclusion of the Nuvinci N360 CVP hub (continuously variable planetary). Since the Nuvinci hub has continuously variable gearing and you can shift smoothly at any time, under any load it would seem to be the perfect hub to mate to an automatic shifter. With the Lime you weren’t really sure sometimes when it would shift, and it was limited to those three gears. The auto bike seems to promise what we all thought when we first heard of a CVT bicycle hub – truly automatic, variable shifting. Apparently, riders will be able to set their ideal cadence either through buttons on the bike, or with their smart phone via Bluetooth. The question that hasn’t been answered yet, however, is how often the shifter is actually shifting the hub – is it continual? Every 5 seconds? 10? Hopefully we can find out and report back. UPDATE: The system analyzes the rider’s actual riding condition (speed, grade, gear ratio, cadence) hundreds of times per second, and has the ability to shift multiple times per second if required. The result is the rider never even feeling individual shifts, because the steps are so small and unnoticeable, yet always feeling like they are in the perfect gear.

Autobikes will be offered in Standard and step through frames, apparently in a one-size-fits all kind of deal. Fortunately it is a very pedal forward design with a slack seat post. There are multiple color options, and initially at least, the Autobike will retail for $999.95 with free shipping on the first 500 orders with a scheduled delivery of Spring 2013.

You can read the full article here.