All Fat & Charged Up: Electric power where it’s never been before

FatIMGL7021Fat bikes have seen a huge spike in interest the past few years in the mountain bike community. From rocks, sand and snow, their huge 3- and 4-inch-wide tires give riders the chance to float easily over every type of terrain where normal mountain bikes would bog down. The problem is, though, pushing those oversized wheels and tires with only human power is a tall order. That’s a lot of rubber to push.

This year we’ve seen several companies latch on to the huge traction and supple-ride benefits of the fat bikes, and add electric motors to the mix, thereby removing the main issue most riders have with fat bikes. If you’re not solely responsible for the energy to get those big wheels a turnin’, what reason do you have to not go big?


While attending the recent Interbike trade show in Las Vegas, we set out for the nearby Bootleg Canyon to partake in the Outdoor Demo, where hundreds of bikes of every variety were being test-ridden by dealers, journos and shop groms. And so it came as no surprise to find a couple of fat e-bikes running along the rough desert trails.

Of course, as big (no pun intended) as the fat-bike industry has grown in the last few years, we had yet to see the bikes evolve into the world of pedal-assisted power. And really, after cargo bikes, fat bikes are probably the one category of bikes where an extra dose of power would always be useful.


E-Bike-Mike-2The most polished of the two bikes we got close to was the aluminum Felt Lebowsk-e, which was actually just a concept bike. In talking to Felt product manager Brian Wilson about the bike, he said that as the SoCal bike company talked about entering the fat-bike market, it occurred to them that the most sensible approach would be to make the bike an electric bike.

“Fat bikes aren’t known for their precise riding traits, but we still wanted to make sure the bike handled as best as [it] could. We spent plenty of time making sure the standard fat bike was designed right, with the correct geometry, fork offset and front-center. We went with 4-inch tires for two reasons: to make sure the Q-factor was what we wanted, and since the bike is spec’d with an 11-speed cluster, we wanted to make sure the chainline was workable.”

Brian added that the bike was really designed to be optimal for both dirt and pavement use and not specifically as a “snow bike,” as many people presume from looking at the oversized wheels. And although the retail price isn’t fixed, he said it would be close to the $6000 mark.


The compact Bosch drive unit allows the electric power to use the cassette and derailleur as a transmission.
The compact Bosch drive unit allows the electric power to use the cassette and derailleur as a transmission.

The Lebowsk-e we had a chance to ride was equipped with SRAM’s XX1 drivetrain, Paul sealed bearing hubs, 80mm double-walled aluminum rims, custom cold-forged cranks, a Reverb Stealth dropper post, Easton Carbon EC90 stem and Haven Carbon bars, Vee Rubber V8 26×4 tires, and internal cable routing.

The bike uses the Bosch pedal-assist unit, offering up to 350 watts and a max of 60NM. The battery life claims to last more than 2 1⁄2 hours of real mountain bike riding at maximum power-support level. On the road, with road tires, Felt claims you can go up to 70 miles. The Bosch unit weighs 6 pounds, and the battery takes 3 1⁄2 hours to fully charge. The improved drive system with more-powerful electronics and a low-vibration motor, as well as low volume and weight, convinces the rider it’s capable of hitting real mountain bike trails with ease.

The new cycle computer, Intuvia Performance, is the nerve center of the bike and features simple and intuitive operation through the separate remote control mounted to the handlebar. The optimized three-sensor concept takes measurements 1000 times per second, with maximum precision for optimal power tuning and a new, unique riding experience. Switching between the five riding modes, plus walk assistance, and looking up information such as speed, charging state and distance remaining on the current charge is simple and easy to understand.

Even when removed from the e-bike, Intuvia remains a useful informational tool that makes it possible for you to retrieve all your ride data via a USB cable that can be connected to any computer. The USB port also allows you to charge external hardware such as smartphones and MP3 players. With Intuvia Performance, the e-biker can make a fine adjustment to the wheel circumference at the touch of a button. As an added bonus, the five available riding modes—Turbo, Sport, Tour, Eco and Off—can be easily and conveniently selected via the separate control unit without having to take one’s hand off the handlebar.

Brian said that they had hoped the bike would be hitting U.S. shores sooner than the now-planned May delivery, but that the delay of motors from Bosch was slowing things up.


The Canandian based BioniX makes a wide variety of power units to help you master almost any terrain.
The Canandian based BioniX makes a wide variety of power units to help you master almost any terrain.

The other fat e-bike making the rounds was actually based on a Surly Pugsley fat bike with an aftermarket BionX power system bolted on. While Surly is a leader in the fat-bike market with three different models to choose from, what they don’t offer (and apparently have no plans to offer) is an electric version of any of their bikes. Oh well. A complete Pugsley bike sells for $1750.

As for the BionX system, the company is well advanced in the accessory motor business. Headquartered in Aurora, Ontario, Canada, BionX International has various locations and sales partners in over 15 countries. Their Aurora facility serves as the center of global operations for sales, service, marketing, testing, sourcing and resident engineering. It is also home to the main BionX production and assembly plant where the e-bike systems, consisting of a battery, motor and console, are produced.

BionX e-bike systems were first introduced to the market over 10 years ago as a retrofit product on any bicycle. The systems eventually evolved and became available as standard equipment on complete electric bicycles in 2008.

As far as product offerings, BionX has eight different motor, battery and wheel combos in their lineup, ranging in price from an $1199, 243-watt system to the higher-end $2099, 423-watt system.

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