Electric bikes are everywhere these days, with folk seemingly too lazy to bother peddling anymore. Alongside being a very good way to arrive at a meeting not drenched in sweat, they are big business for those making them, with uptake increasing year-on-year. Also, a subsidiary of US electric pick-up and SUV maker Rivian, wants to get in on the action with an innovative and very tech-y approach to the eBike.
Instead of being a one-size-fits-all commuter, or an all-out, battery-powered downhill MTB, the TM-B is designed to be flexible, practical and easy to live with — a bike that can adjust to what you need, rather than forcing you to adjust to it – ie. having to buy new one for every application.
The standout feature of the TM-B is its modular top frame system. In simple terms, the part of the bike where the seat and rear section sit can be swapped in seconds. Want a standard saddle for city commuting? Easy. Need a cargo-style setup for groceries or a child seat? Done. There’s even a low bench option that gives the bike a more scooter-like feel. Each module locks in securely via a clever electronic latching system and powers its own lights, so safety isn’t compromised.
Instead of a traditional drivetrain, the TM-B uses a pedal-by-wire system called DreamRide… something that’s completely new to the industry. With nary a chain or a belt-drive connecting the pedals to the rear hub, the system senses how hard you’re pedalling, the gradient, and the level of assistance you’ve selected, adjusting automatically. There are ten levels of support, so beginners can enjoy a gentle ride, while more experienced riders can get more boost when they want it. You can even simulate gear changes for a slightly more traditional feel if you like.
The TM-B is a Class 3 e-bike in the US, meaning pedal assistance up to 28 mph, with the appropriate limits imposed to ensure it is legal in other markets. The removable battery gives around 100 miles of range and doubles as a portable power source via USB-C ports, handy for charging gadgets or small devices on the go.
“The standout feature of the TM-B is its modular top frame system”
It’s packed with tech, as you would expect. The Portal touchscreen on the handlebars makes it easy to manage assistance, music, or security. Your phone acts as a key, automatically powering the bike on when you approach and locking it when you walk away. If it’s ever stolen, the system can remotely disable the battery, motor, and display, making it unusable.
Founder Chris Yu told Flat-Out that every piece of technology on the bike can be remotely “bricked” by the app in the case of theft, with the battery, DreamRide drive unit and touchscreen all “Apple-level” disabled, meaning the bike could only really be sold as scrap on the black market.
What makes the TM-B stand out isn’t just its tech. The bike is easy to ride, with a low centre of gravity, upright seating, and intuitive controls. Its modularity means one bike can handle commuting, errands, or even carrying a child or small cargo. Switching between setups is quick and simple, so it genuinely adapts to your life.
At roughly $4,000 (£3,000), it’s not cheap, but it’s also not expensive in the world of £15k eBikes. The flexibility and convenience make it a reasonable proposition for anyone serious about urban mobility. The first TM-Bs are expected to arrive in the US in spring 2026, alongside a range of accessories and top-frame options, as well as a very flashy Alpha Wave helmet, which integrates lights, speakers and microphones for joining that Zoom call on the go.
