I found many reasons to embrace the new city-friendly of Diamondback Union 1 ebike this summer, that record heat and months of forest fire smoke made other forms of cycling less fun. Add to this atmospheric turmoil an excess of road building in my town and rising gasoline prices that have turned car racing into a baked nightmare. The saving grace was the Union 1, an electric bike that brought joy, speed and style to forays into the city, especially those that ended on a beach.
Best known for its “acoustic” gravel and mountain bikes, Diamondback is new to the growing e-bike niche, but its parent brand, Alta cycling group, who also owns IZIP, Raleigh and Haibike, is not. Alta’s institutional e-bike history means Diamondback didn’t have to reinvent the wheel (or motor) until it launched four models of e-bikes this year, a mid-priced urban warrior lineup that each offer high performance components, rugged construction and subtle class.
Of the four, the aluminum-framed Union 1 is the cheapest but still impressive. It is built around a Bosch Performance line speed motor that, with its 85 Newton-meter drive unit, helps the rider reach higher speeds and cover longer distances — 35 to 55 miles per charge, depending on the level of pedal assist you dial . Classified in class 3 ebike, the Union 1 reaches a maximum of 28 mph, the maximum speed allowed on an ebike in the United States. The motor is powered by a 400 watt-hour battery fully integrated into the down tube, reducing the overall footprint. The 10 speed Shimano The transmission makes shifting easy, and the hydraulic disc brakes (as my bike shop mechanic noted after a test drive in the neighborhood) are tough enough to stop this 51-pound machine very quickly, which is not. not always the case on electric bikes. The no-frills, minimalist Bosch Purion computer display on the left handlebar displays big numbers on a black and white LCD screen, so it’s easy to read. The sturdy 27.5-inch wheels are mounted on tires that have an urban tread large enough to withstand even rough asphalt and pavement. Integrated bike rack and mudguards keep bags on the bike and mud out of the rider.
The best part of Union 1 is its smooth and seamless ride. Like most Bosch e-bikes, the motor offers four modes: Eco, Tour, Sport and Turbo. Add the 10 gears to the transmission and your options range from nearly impossible uphill workouts in Eco mode to effortless pedaling reminiscent of rocket launch in Turbo mode.
When I ride an e-bike I’m less concerned with exercise and more interested in fun, which means I tend to keep the bike in Turbo mode as long as the battery has juice. On my last 12 mile ride, which required a 1,200 foot climb partly over gravel roads after stopping to get off the bike and jump into Lake Superior to cool off, I was impressed that I didn’t only burnt 40% of the battery even while keeping the bike in Turbo all the time. On longer rides in the 20-30 mile range, I recalled it to the more conservative Tour or Sport mode, but battery power rarely dipped to dangerously low levels. The ultra-conservative Eco mode is ideal for those who want a real workout or who cover more than 35km on a single charge, but I found the force of pedaling the Union 1 in Eco squeezed my knees, especially on the climbs. For more details on the cited range of bike in each mode, see Diamondback’s how-to guide autonomy calculator.