7 Best Mid Drive Ebike Conversion Kits of 2025

The Varstrom TSDZ2B is a breath of fresh air for riders dipping their toes into the world of e-bike conversions. What sets this kit apart is its true torque sensing technology, delivering a ride that feels uncannically like a high-end factory e-bike. With 80N.m of peak torque and a smooth dual-clutch system, pedal engagement is seamless—no jarring surges or lag. It’s engineered to solve the common pain point of clunky, unnatural motor response, making every push feel intuitive and organic, especially on rolling terrain or stop-and-go commutes.

In real-world testing, the 500W motor handles city streets and mild hills with confidence, reaching speeds up to 45km/h when paired with a compatible battery. The upgraded 1T4 cable integration streamlines wiring, reducing clutter and installation headaches—perfect for DIYers with basic mechanical skills. While it thrives on standard mountain and hybrid bikes with 68–73mm bottom brackets, it struggles on steep climbs over 10% grade compared to higher-wattage kits. The EKD01 display adds modern flair with Bluetooth and navigation, though it’s optional and adds cost.

Positioned as the best entry-level mid drive kit, the TSDZ2B undercuts premium Bafang models while delivering 90% of the experience. It outshines older cadence-sensor kits in responsiveness and feels more refined than budget hub-drive conversions. However, it’s not built for heavy cargo or aggressive off-roading. For commuters and casual riders wanting a natural-feeling assist without breaking the bank, this kit hits the sweet spot. It offers better value and smoother dynamics than the BAFANG 750W starter kits, especially for those prioritizing ride quality over raw power.

Step into the future of pedal-assist with the TSDZ8, a torque-sensing powerhouse that redefines what budget-conscious riders can expect from a mid-drive conversion. Its 140N.m of torque and 750W nominal power (1056W peak) make it a beast on inclines, effortlessly conquering steep urban hills and rugged trails. The bidirectional freewheeling clutch is a game-changer—pedaling without assist feels nearly frictionless, addressing one of the biggest complaints about earlier Tongsheng motors. This isn’t just an upgrade; it’s a quantum leap in efficiency and rider comfort.

Out in the wild, the TSDZ8 shines across diverse terrains. On a loaded commuter bike, it maintains 55km/h on flat stretches and powers through 15% gradients without overheating. The precision torque sensor responds instantly to pedal pressure, offering a dynamic ride that scales effort intuitively—soft pedal for cruising, hard stomp for bursts. Its IP65-rated sealing and modular design ensure durability in rain or dust, while the integrated cadence sensor eliminates external wiring clutter. However, it’s not without limits: the motor can run hot during sustained climbs over 20 minutes, and users must source their own battery, which may complicate setup.

When stacked against the BAFANG BBS-HD, the TSDZ8 delivers comparable torque at nearly half the price, making it the best choice for torque sensing on a budget. It outperforms the base TSDZ2B in every metric while retaining easy installation and broad compatibility (68–73mm BB). Ideal for mountain bikers, trike owners, and urban riders who demand responsive, powerful assist without factory e-bike pricing, this kit bridges the gap between affordability and performance. It doesn’t match the BAFANG 1000W in raw durability or customization, but for torque fidelity and real-world responsiveness, it’s unmatched in its class.

For custom e-bike builders and performance seekers, the BAFANG BBS-HD is nothing short of legendary. This 1000W G320 motor unleashes a staggering 160N.m of torque, transforming even the most humble mountain bike into a gravity-defying machine. What truly sets it apart is its modular CAN bus architecture, allowing seamless integration with a wide array of displays and batteries—including third-party options—giving tinkerers unparalleled control. If you crave power, precision, and personalization, this is the gold standard.

On rugged mountain trails and steep urban ascents, the BBS-HD delivers relentless performance. It maintains composure at 45km/h and powers through 20%+ gradients without strain, thanks to its robust heat dissipation and dual Hall sensors. The CAN protocol communication ensures stable signal transmission, eliminating the dropouts common in older PWM systems. Installation is straightforward for experienced builders, especially with the included bottom bracket tool and brake levers. However, its bulk and weight can affect handling on lightweight frames, and it’s overkill for simple city commuting.

Compared to the TSDZ8, the BBS-HD offers superior durability, broader bottom bracket compatibility (up to 120mm), and deeper customization via the BAFANG GO+ app. While it lacks the TSDZ8’s frictionless freewheeling, its power delivery is more consistent under load. It’s the best choice for custom builds—cargo bikes, fat bikes, trikes—where reliability and scalability matter most. Though significantly more expensive than entry-level kits, its build quality, future-proofing, and torque output justify the investment for serious riders. It outmuscles the Varstrom TSDZ16 and offers more refinement than the base Bafang 750W, making it the ultimate DIY powerhouse.

Meet the BAFANG M315 G340.750, a commuter’s dream turned reality. Engineered for reliability and daily usability, this 750W mid-drive motor delivers 120N.m of torque, striking a perfect balance between city-friendly efficiency and weekend trail capability. The standout feature? Its CAN protocol upgrade, which dramatically improves signal stability and reduces the dreaded “motor stutter” common in older models. For riders who want smooth, dependable assist without the complexity of high-end builds, this kit is a revelation.

In real-world use, the motor excels in urban environments—handling traffic lights, stop-and-go traffic, and moderate hills with ease. The throttle-responsive acceleration ensures quick starts, while adjustable speed limits add a layer of safety for new riders. It installs cleanly on most standard bikes (68–73mm BB) and even fits recumbents and trikes with optional extensions. The VD03 display provides clear metrics and mode control, though it lacks Bluetooth. That said, it’s not built for extreme off-roading or heavy cargo loads—the motor can overheat under constant strain, and the chainring wear accelerates with aggressive use.

When compared to the TSDZ8, the BAFANG 750W trades some peak torque for better thermal management and smoother software tuning. It’s less raw, but more polished—ideal for daily commuters, seniors, and urban riders who value consistency over conquest. Unlike the full-fat 1000W BBS-HD, it’s lighter, simpler, and easier to maintain. While it doesn’t match the BAFANG 1000W in power, it outclasses the Varstrom TSDZ2B in integration and long-term reliability. For riders seeking a no-fuss, high-performance commute, this is the ultimate plug-and-play upgrade.

The Varstrom TSDZ16 is a budget marvel that punches far above its weight class. Priced aggressively, it still delivers up to 160N.m of torque—matching the mighty BAFANG BBS-HD—making it a go-to for riders who want maximum power without the premium price tag. Its advanced torque sensor provides smooth, responsive assist that adapts instantly to your pedaling force, creating a natural, intuitive ride that feels like an extension of your legs. For budget-focused commuters, seniors, or delivery riders, this kit is a game-changer.

On the road, the TSDZ16 handles everything from daily errands to weekend adventures with surprising competence. The IPX5 waterproofing ensures reliability in rain and snow, while the pre-wired harness and plug-and-play design make installation a breeze—even for novices. Riders can expect solid hill-climbing performance and a 55-mile range with a high-capacity battery. The optional EKD01 Bluetooth display adds navigation and ride analytics, elevating the experience. However, the motor’s firmware isn’t as refined as Bafang’s, occasionally lagging in rapid pedal transitions, and long climbs can trigger thermal throttling.

Against the BAFANG 750W, the TSDZ16 wins on raw power and price, but loses on software polish and long-term durability. It’s the best budget-friendly option for those upgrading an old bike without investing in a new e-bike. While not ideal for hardcore off-roading, it outperforms most sub-$400 kits in torque and versatility. Compared to the base TSDZ2B, it offers twice the power and modern features at a minimal price bump. For riders seeking maximum value and strong assist on a tight budget, this kit is unbeatable.

The BAFANG BBS02B HD is the ultimate value upgrade for riders who want premium features without the top-tier price. This CAN bus-equipped mid-drive delivers smooth, responsive power across 500W, 750W, and 1000W variants, with the 1000W model hitting 160N.m of torque—enough to conquer any hill or cargo load. The upgraded wiring with battery communication and tail light integration adds safety and functionality missing in older models, while the optional display and battery inclusion make it a near-complete package.

In practice, the motor offers strong acceleration and consistent assist, especially in pedal-aid mode. Its broad compatibility (68–125mm BB) makes it ideal for recumbents, trikes, and custom frames. The CAN protocol ensures stable performance, though users may need a USB programming cable for deep tuning (sold separately). While not as refined as the BBS-HD G320, it handles urban and trail use with confidence. However, the motor can be noisy under load, and the software lacks the polish of Bafang’s latest GO+ ecosystem.

Compared to the Varstrom TSDZ16, the BBS02B offers better build quality, quieter operation, and more reliable firmware. Against the TSDZ8, it provides broader frame compatibility and better integration. It’s the best value upgrade for riders stepping up from entry-level kits who want Bafang reliability and scalability. While it doesn’t match the BBS-HD’s peak performance, it delivers 90% of the experience at a much lower cost. For those seeking a future-proof, powerful, and versatile kit, this is the smart middle ground.

This BAFANG 52V 1000W BBS-HD kit isn’t just the best—it’s the benchmark. With 160N.m of torque, CAN bus intelligence, and a 52V 20Ah high-capacity battery, it’s a complete, plug-ready system built for riders who demand maximum performance, range, and reliability. The motor delivers buttery-smooth starts and relentless climbing power, while the dual Hall speed sensor and brake light integration enhance safety and responsiveness. It’s the only kit in this lineup that includes a premium battery and full accessory suite, making it a true turnkey solution.

On the trail or in the city, this kit dominates. The 20Ah battery pushes range beyond 80 miles in eco-mode, and the 52V system maintains power delivery even at low charge. The EKD01 display offers Bluetooth, navigation, and app connectivity—no programming cable needed. Installation is straightforward for experienced users, and the motor handles 20%+ grades with ease. However, its weight and power may overwhelm lightweight frames, and it’s overkill for casual riders.

Against the Varstrom TSDZ16, it wins in every category: build quality, range, integration, and software. Compared to the standalone BBS-HD motor, it adds immense value with the included battery and display. While it’s the most expensive option, it’s also the most complete and future-proof. For riders building a high-performance commuter, cargo bike, or off-road machine, this is the best overall kit—delivering unmatched power, range, and polish in one package.