E-bikes are here to stay, and one of the biggest open directions for the market is in making the price point more accessible to budget-minded consumers. Diamondback has long been a company that artfully blends performance with economics, and I still shred around on their sleek Sync’r Carbon. Naturally, I was excited when they announced their new line of E-bikes, and even more stoked when they sent me a Union 1 for review.
Diamondback Union 1 E-Bike Features:
- Formed 6061 T6 Oversize Aluminum Alloy frame with Powertube integrated battery
- Shimano Deore SL-M6000 10 speed
- Tektro M735 2-finger lever hydraulic brakes
- Bosh Performance Line Speed, 85Nm torque motor
- Bosch Purion display with PowerTube 400 battery
- Includes aluminum fenders, integrated rear rack, mounted kickstand
- Weight: 51 lbs.
- MSRP: $3,500

Get ready to (not) get sweaty
I guess the reason that I was interested in an E-bike was for a better way of integrating cycling into my life. I say that with my tail tucked between my legs a little, since generations of bike commuters have made do with a human-powered machine. But, for me, the excuses are common ones: I get really sweaty and don’t always have access to a shower; I live in a hilly city; I’m often booked up and need to move quickly to maximize my day’s schedule. So, I started looking around for an E-bike. Being a student, I tend to look for cost-effective options and that made the Diamondback models intriguing.
I’ve been testing the Union 1 since the early Fall, and was able to ride this great bike all over Spokane during one of its rainiest times of year. That made for great testing of the bike’s ability to handle weather, and to keep my legs and butt as dry as possible with the integrated fenders. There are plenty of other features that make the bike easy to use, including these fenders, the integrated kickstand and rear cargo rack. We’ll touch on those more later, but let’s talk tech specs.
This is a Class 3 e-bike, which I guess you could call the most ‘aggressive’ licensed category in the US. It means that it has a pedal assisting motor that will power the bike up to 28MPH, but no further. Class 1 is pedal assist up to 20MPH, and Class 2 is throttle up to 20MPH. If you’ve never ridden an e-bike, the pedal assist technology is pretty neat because it senses your own legs moving the pedals, but puts oomph into that motion to power you up hills or across flats.

Diamondback built in a premium 350W Bosch Performance Line Speed motor, which is powered by a Bosch PowerTube battery that’s sleekly integrated into the downtube. Asthetically you can definitely tell it’s an e-bike, but it’s a little more discrete than the models that have the battery mounted externally to the down tube.
This combination provides plenty of power. For me, I love to ride this bike just for the fun of it and never needed to do a commute of more than 8 miles or so each way. So, of the bikes four settings (off, eco tour and turbo), I kept things at the highest ‘turbo’ all the time. The Bosch Purion computer makes it easy to see quick stats about your ride: your battery life, speed, mileage and mode are all displayed in a no-frills but readable display on the handlebar. The buttons are big and the important ones for riding are on the front, so it’s easy to mash them even if you’re wearing gloves.

It’s tough to estimate mileage on a charge because this is determined by many factors – distance, speed and even the loaded weight of the bike. My commute has two nasty hills, and those definitely can take a chunk out of the battery life if you’re abusing your ‘turbo’ privileges like I was. With that said, Diamondback estimates the range as 35 miles to 55 miles, depending on your power settings and usage. I think that’s realistic: you can easily deplete the battery during a single day of riding if, as in my case, you’re taking multiple trips within a day that total into the 30 mile range. My solution, and what I recommend for others, is just to charge this after each use.
That’s enough of the motor stuff, let’s talk about some other important parts of this bike. Shifting is accomplished by 1×10 speed Deore setup, which offers reliable-if-clunky performance. Deore is a no-frills groups but it’s known for its reliability, and I will say that once the cable stretch was broken in I had no issues with the shifting through the several months of my testing period. If you put on your rose-tinted glasses, you can take the loud ‘THUNK’ of the Deore derailleur dropping into gear as a feature to confirm when you’re in gear.

Stopping is provided by equally no-frilled Tektro hydraulic disc brakes, 4 piston 180mm rotor front and 2 piston 160mm rear. You power these through two-finger Tektro levers, and when you’re cruising fully loaded at 28MPH you will need that stopping power. This combination does provide adequate stopping power, thanks in no small part to that 4 piston 180mm rotor setup up front. The thick Schwalbe 27.5″x2.4″ Super Moto tires provide a plush ride for a rigid bike, and offer reasonably good traction in both dry and wet pavement conditions.
The problem with this, which plagues brakes at this lower price point, is that it’s hard to modulate the power. There is just less room between ‘off’ and ‘on,’ and at times the brakes can feel grabby. That’s OK most of the time, but can lead to some scary situations if you’re on loose surfaces or need to brake in the middle of a turn.

Some of the built-in features are just rad. I love the heavy, full-coverage fenders which absolutely shut down any water flinging off the tires. I road this home through several heavy rain storms, and had to laugh when my thighs got wet from rain but my shoes and lower legs stayed mostly dry thanks to the aggressive fenders.
Similarly, the built-in cargo rack totally takes care of business. I spent most of my time cruising around with either one or two panniers depending on the day. The Union 2 comes with integrated head and taillights, which would have been a nice perk, but it’s easy enough to put my own light on the rack or seat post.

Rounding things out, the cockpit components are functional but budget-minded. There’s a thoroughly unsexy-yet-comfortable (although can’t comfort be sexy?) ‘Custom Ergo Performance’ saddle and Diamondback-branded aluminum bars and seat post. This, plus the battery and heavy wheels, mean the bike weighs in at just over 50lbs. Keep that in mind if you’re an urbanite with three floors of stairs to climb to your apartment: the bike really does best if it stays on the ground.

The Good
- Tons of power available with the benefits of a proven Bosch system
- Decent range for fully loaded commuting
- Simple, intuitive display and pedal assist technology make riding second nature
- I love the integrated rack and fenders
- Tektro stoppers are quite strong and Deore shifting is reliable
The Bad
- It’s a heavy ol’ sucker at 51lbs
- Tektro stoppers lack refinement, and Deore shifting is loud and coarse
- Budget cockpit components add weight, but potentially double as theft deterrent?
The Bottom Line:
It’s no mean feat to make a full-fledged Class 3 e-bike at the price point of $3500. I love the relatively sleek look of the integrated battery, as well as commuter-friendly accents like the rack and fenders. This comes at the cost of some thoroughly budget-minded components as we’ve discussed, as well as clunky cockpit components. For someone like me though, who wants to add non-sweaty bike commuting into my lifestyle, the performance at this price point is just stellar.
Buy now: Available at Diamondback.com
1 Comment
I electrified a Diamondback Division 1 last year with a Bafang 750 watt kit and now it looks a heckuva lot like the Union 1! Total cost, about $1400 so that $3500 price point looks pretty steep from here….nice bike though.