June 25, 2025 - (Inning am Ammersee, GER) German technology specialist TQ unveiled a new revolutionary and category-redefining system at the 2025 Eurobike – the TQ-HPR40 Drive System for road and gravel bikes. Weighing in at a mere 1.170 grams, the new TQ-HPR40 motor delivers 40 Nm of torque and up to 200 Watts of power while the system around it enables an unprecedented level of system integration. Utilizing the benefits of TQ’s patented Harmonic Pin-Ring Transmission, the HPR40 Drive System allows for the creation of extremely light yet powerful, nearly silent, virtually instantly-engaging and natural-feeling E-Bikes. E-Gravel Bikes without bulky bottom brackets or gigantic downtubes. E-Road Bikes that look, sound and – most importantly – feel like analog road bikes but give you the sensation of riding on the fittest day of your life.
Even though E-Bikes have carved out a substantial place for themselves amongst mountain biking, trekking and urban cycling over the last decade there has barely been an E-Road segment to speak of until today. But why? As avid cyclists of all disciplines, the team at TQ couldn’t help but try and answer that question and quickly realized that there were three main problems – the design, the ride-feel and the 25kph limit. Road bikes are incredibly sleek performance machines with aesthetics that simply don’t match with the gigantic downtubes and bulky bottom brackets that characterize most E-Bikes. On top of that, the weight and function of most E-Bike systems drastically change and distort a bike’s characteristics, kinematics and ride feel when pedaling. And lastly, if you’re trying to pedal an average of 35kph what’s the point in a system that replaces support with drag from 25kph upwards? It turns out that solving these three issues was exactly the challenge the team of cycling-crazed engineers at TQ sought after and TQ’s patented Harmonic Pin-Ring (HPR) Transmission was exactly the right tool for the job.
The key to TQ’s E-Bike drive systems is the patented Harmonic Pin-Ring (HPR) Transmission which is the result of the German technology company’s decades-long experience in the engineering and development of electric motors for robots, satellites, space stations and mars rovers. By redesigning and reengineering the patented Harmonic Pin-Ring technology used in literal Space-Age applications to fit the needs of cyclists, TQ created an extremely light drive unit (1,170 grams) that is quiet, has virtually no lag in engagement, no drag when coasting and allows for seamless and elegant E-Bike system integration.
With a total system weight of just 2,700 grams including the 290Wh battery as well as a form factor and level of integration that ensures that the system all but disappears behind the chainring, the TQ-HPR40 Drive System allows for the design of E-Bikes that look like analog bikes. Factoring in the integrated freewheel and drag-free internal components of TQ’s HPR transmission that allow a rider to pedal and coast above 25kph without any additional drag and the brand-new HPR40 Drive System challenges all three issues like no other system before. But that’s not all.
The new TQ-HPR40 system features an industry-redefining level of third-party integration by allowing almost all electronically powered components like shifters, lighting, sensors or other peripherals – regardless of the manufacturer – to be powered by the main battery via open interfaces and to be combined into one cohesive system. You want to use the remote buttons on the handlebars to turn on the lights? Go ahead! You want to shift gears upwards with a short press of the left button and downwards with a long press of the right button? Odd choice but feel free. As of launch, the TQ-HPR40 Drive System is compatible with electronic components from Shimano, Sram, Garmin, Hammerhead, Sigma and Wahoo. But what kind of rider is the new system for?
The new TQ-HPR40 Drive System enables the creation of E-Bikes that support riders on climbs without dragging them back on the flats. It provides up to 200 Watts of extra power that elevate an average rider to Tour-winning power levels on the steepest of climbs and allows mixed groups of all abilities to ride together. It allows beginners to keep up with the people that introduced them to the sport and gives experts a training aid that keeps them climbing at peak power even on recovery days. It challenges strong head winds and mountainous terrain with a constant tail wind exactly when and where it is needed with a range of up to 130km and 2000m of climbing. The one rider it is not made for, though, is the one who want to fly up a mountain without breaking a sweat.
In essence, the TQ-HPR40 allows bike manufacturers to create super lightweight E-Bikes that look, feel and sound like analog bikes but take you further. It creates E-Road Bikes that let riders climb higher and faster without weighing them down. It creates E-Gravel Bikes the that are sleek, lightweight and let you explore deeper. It creates E-Bikes that enable you to go on bigger, longer, further and higher adventures and have more fun doing it.
Details TQ-HPR40 Drive System
The System
Building on the success of TQ’s light- and full power systems like the HPR50, HPR60 and HPR120, the brand-new TQ-HPR40 Drive System is aimed at E-Road and E-Gravel riders. With a total weight of just 2,700 grams including the 290Wh battery as well as an incredibly compact form factor, the revolutionary new system allows bike manufacturers to create super lightweight E-Road and E-Gravel Bikes that look, feel and sound like analog bikes but take you further. On top of that, the TQ-HPR40 Drive System features a level of third-party integration that is unprecedented in the E-Bike market.
The Drive Unit
The HPR40 Drive Unit weighs a mere 1,170 grams and delivers up to 40Nm of torque as well as up to 200 Watts of peak power with the highest torque density on the market in an ultra-compact, super-lightweight package. But for TQ it’s not about numbers, it’s about the riding experience.
Believing that the principle of ‘less is more’ doesn’t just ring true when it comes to size, weight and noise, but also when it comes to user friendliness, the system intentionally features only three ride modes which are, however, fully customizable through the TQ App. Additionally, the Q-factor of the drive unit is identical to analog bikes which allows for the same natural and efficient feel at the pedals – something that’s often overlooked when it comes to E-Bikes.
The Battery
TQ’s batteries are well-known for their comparatively small size and low weight which allows for the design of E-Bikes that look like and have the same kinematics as analog bikes. The new 290Wh battery is no exception and was specifically developed to power the HPR40 Drive Unit with maximum efficiency in the most compact package possible. Weighing in at only 1,460g, it delivers the best ratio of weight to capacity in its class thanks to featuring the highest energy density on the market. The capacity of the battery can also be increased by a further 160Wh for those extra-long all-day epics thanks to an optional range extender the size of a 500ml water bottle.
The Controls
The smallest parts of the TQ-HPR40 system are the ingeniously hidden ‘display’ and remote. While the remote consists of several buttons that are completely hidden under the handlebar tape, the ‘display’ is neatly integrated into the bar end. The ‘display’ is in parenthesis because it isn’t a screen but rather a neatly integrated on-off button with a row of sleek LED’s that display the battery charge status as well as the selected support mode the rider is in.
An Integration Masterclass
The sleek integration of the physical parts of the TQ-HPR40 System is only one part of the story, though. The other part is the next-level electronic system integration that the TQ Smart Box, the Remote and the TQ App offer. Made possible by the TQ Smart Box which is neatly hidden inside the frame, the TQ-HPR40 System provides an open system architecture for third-party integration such as electronic shifting, lighting and much more as well as an open interface for OEM customization and full compatibility with Sram and Shimano hood buttons. You want to use the remote buttons to turn on the lights? Go ahead! You want to shift gears upwards with a short press of the left button and downwards with a long press of the right button? Odd choice, but feel free. As of the launch of the TQ-HPR40 Drive System, the Smart Box is compatible with Shimano, Sram, Garmin, Hammerhead, Sigma and Wahoo.
But that’s not even all. Any system that is integrated into the bike, like for example a lighting setup, can be powered by the main battery directly and continuously. In addition, the team at TQ made sure that relevant data from the system’s sensors including power input can be transmitted via ANT+ onto a cycling computer which for example eliminates the need for a separate power meter.
The Harmonic Ping-Ring Transmission
The Harmonic Pin-Ring Transmission (HPR) is the result of TQ’s decades-long experience in the development and engineering of electric motors for robots, satellites, space stations and mars rovers. By redesigning and reengineering the patented Harmonic Pin-Ring technology used in literal Space-Age applications to fit the needs of cyclists, TQ created an extremely light drive unit (1,170 grams) that has virtually no lag in engagement and allows for seamless and noiseless E-Bike system integration.
By making full use of the benefits of the compact size and technological advantages of the HPR Transmission, TQ developed a light and extremely compact nested motor construction around the bottom bracket that consists of only very few parts and lets the motor almost completely disappear behind the chainring. Furthermore, the HPR transmission avoids the use of cog wheels which cause friction, noise, wear and potential points of failure. Foregoing cog wheels enables the design of E-Bikes which sound, look and ride like analog bikes. Lastly, an HPR40-equipped E-Bike pedals like an analog bike when the drive unit is disengaged thanks to an integrated freewheel and drag-free internal components.
Further information on TQ and the technology behind the HPR40 Drive System can be found here.
