Frame-only e-bike builds let riders upgrade performance, durability, and style without replacing an entire bike. For American riders, choosing a frame requires understanding materials, compatibility, and power readiness, especially for higher-watt kits. The five frames highlighted here cover steel and aluminum constructions, varied wheel options, and straightforward assembly guidance. They emphasize durability under 3000–8000W kits, yet still fit common mid-drive and hub-motor configurations. In addition to raw strength, considerations like paint finish, shock mounting, dropout width, and battery integration matter. This guide provides concise product sections, a quick spec table, and a practical buying guide to help you compare options and pick the frame that aligns with your build goals.
| Product | Brand | Frame Type / Material | Notable Feature |
|---|---|---|---|
| NBPOWER Enduro Ebike Frame | NBPOWER | Steel Frame | ABS+PMMA anti-scratch cover; 190–240mm shock compatibility |
| SZWEDI Stealth Bomber Frame | SZWEDI | Full Steel Frame | 175mm dropout; fits 24–26″ wheels and 4.0″ tires |
| MOONCOOL Aluminum Frame E-Bike | MOONCOOL | 6061 Aluminum Frame | Removable battery; third-party electrical safety certification |
| Viribus Aluminum Frame E-Bike | Viribus | Aluminum Frame | 65-mile pedal-assisted range; 48V 13Ah battery |
| Funhang Step-Through Frame E-Bike | Funhang | Step-Through Frame | Removable battery; UL2849 certified; 1000W peak motor |
NBPOWER Enduro Ebike Frame
The NBPOWER Enduro Ebike Frame is designed for high-watt builds that push power from 3000W to 5000W, making it suitable for electric mountain bike projects that demand serious trail performance. It combines a steel frame with a glossy ABS+PMMA anti-scratch plastic cover, delivering durability and surface protection against mud, rocks, and debris encountered on rugged descents. The frame geometry prioritizes stability and compatibility with long-travel rear shocks, offering 190mm to 240mm shock options to accommodate aggressive suspension setups. It is aimed at DIY riders who want a robust platform for future upgrades and component swapping.
- Steel construction for stiffness and impact resistance
- ABS+PMMA protective shell for frame finish protection
- 190mm–240mm rear shock compatibility for long-travel setups
- Standard dropout spacing to simplify mounting and alignment
Practical considerations for builders include ensuring proper alignment with your fork and wheel choice, confirming brake mounting compatibility, and planning for appropriate cable routing and battery integration. The NBPOWER frame provides a solid base for up-sizing power while maintaining serviceability, and its protective shell helps preserve the frame finish in tough riding conditions. This frame excels for riders aiming to finish a capable, high-watt setup without sacrificing frame longevity or ease of maintenance.
SZWEDI Stealth Bomber Frame
The SZWEDI Stealth Bomber Frame is built from full steel to handle heavy-duty use in fat-bike and enduro contexts. Its 175mm rear dropout expands compatibility for both 24–26 inch bicycle wheels and 19–21 inch motorcycle wheels, enabling builders to mix wheel sizes with ease. The frame accommodates 4.0-inch wide tires, expanding traction and stability on snow, sand, or rough surfaces. This package includes the essential mounting hardware for straightforward assembly, making it an appealing option for frame-only projects that require rugged reliability without sacrificing upgrade paths.
- Full steel construction for maximum durability
- 175mm rear dropout supports diverse wheel options
- Compatible with 24–26″ bicycle wheels and 19–21″ motorcycle wheels
- Supports up to 4.0″ tire width for fat-bike setups
Builders evaluating this frame should consider weight and handling trade-offs inherent to steel frames, especially when paired with high-watt power systems. The Stealth Bomber’s wheel compatibility and tire clearance make it a strong candidate for fat-bike builds or rugged all-terrain configurations where traction and robustness are priorities. Its complete hardware set reduces sourcing steps, helping DIY projects stay organized and efficient.
MOONCOOL Aluminum Frame E-Bike
The MOONCOOL Electric Bike centers on a durable 6061 aluminum frame designed to provide a strong foundation for daily commuting and longer rides. Aluminum frames offer a favorable balance of stiffness and lightness, contributing to improved efficiency and ride feel. The MOONCOOL frame is paired with safety credentials from independent third-party testing, underscoring its electrical safety and performance. For builders, a robust frame is the basis for safe battery integration and reliable motor performance, making this a practical choice for frame-focused upgrades that prioritize longevity and predictable handling on varied terrain.
- 6061 aluminum frame for stiffness and lightness
- Removable 36V 10.4Ah battery enables easy charging and swaps
- Independent third-party safety certification documentation available
When planning a frame-only project around this MOONCOOL option, pay attention to fit with your chosen motor system and battery configuration, as well as mounting compatibility for racks, fenders, and lighting. The frame’s strength supports everyday use and weekend adventures alike, and the removable battery design simplifies charging logistics for commuters and travelers who value convenience on the go.
Viribus Aluminum Frame E-Bike
The Viribus electric bike for adults centers on a durable aluminum frame designed to support long-range riding, with a 48V 13Ah battery stated to deliver substantial pedal-assisted mileage. The bike emphasizes a balanced blend of efficiency and capability, offering up to 65 miles of pedal-assisted range and around 35 miles in full-throttle mode in typical use. With a 26-inch wheel platform, the frame integrates a reliable suspension setup, front and rear disc brakes, and a front light, making it a practical choice for riders prioritizing frame integrity, safety, and versatility for city streets and light trails.
- Aluminum frame for strength and weight efficiency
- 48V 13Ah battery for extended range
- Pedal-assisted range up to 65 miles; top speed around 20 mph
- Front and rear disc brakes with integrated headlight for safety
For frame-centric builds, assess compatibility with your battery mounting points and any accessories you plan to attach. The Viribus frame’s emphasis on range and safety features makes it a solid platform for urban commuting as well as weekend exploration, while maintaining a manageable overall weight that aids handling and transport.
Funhang Step-Through Frame E-Bike
The Funhang line includes frame-friendly, high-value options that emphasize comfort and practical daily use. The Step-Through Frame E-Bike features a 48V removable battery and a 1000W peak brushless motor, providing robust power for city commutes and hill climbs without requiring a cyclist to straddle a high-frame bike. A 21.7 MPH top speed and a 50-mile range in pedal-assisted mode (and 20–30 miles in throttle mode) offer versatile performance. The 26″ wheel platform combined with a 7-speed drivetrain and UL2849 safety certification supports dependable daily riding in varied urban environments.
- Step-through frame for easy mounting and comfort
- 1000W peak motor with 48V 374.4Wh removable battery
- PEDAL-Assist range up to 50 miles; throttle mode up to 30 miles
- UL2849 certified; adjustable stem and 7-speed transmission
When selecting a frame-oriented Funhang build, consider how the step-through geometry matches your riding style and height, as well as the anticipated rack, fender, or light attachments you plan to carry. The emphasis on a safe, user-friendly design makes it well-suited for riders prioritizing easy access, steady control, and practical day-to-day use, all while benefiting from modern battery and motor integration.
Buying Guide
Choosing a frame for an electric bike build involves balancing strength, weight, compatibility, and upgrade potential. Below are practical considerations to guide a smart purchase:
- Frame material and weight: Steel frames are extra-durable but heavier, while aluminum frames offer a lighter, stiff structure with good durability. Consider your target riding style and the expected frame load from high-watt kits.
- Wheel size and tire clearance: If you plan to run fat tires or mixed wheel configurations, verify dropout width and tire clearance alignments with the intended wheels (24–26″, 4.0″ tires, etc.).
- Shock compatibility: For frames intended for high travel, confirm rear shock compatibility (e.g., 190–240mm) and how it affects overall geometry, weight, and comfort on rough terrain.
- Battery integration and accessibility: Removable batteries simplify charging and swaps, while integrated packs may yield a cleaner appearance but require more care during maintenance.
- Motor power and controller compatibility: Ensure the frame can handle the motor class you plan to use (3000W–8000W ranges in fat and enduro builds) and that the mounting points, downtube routing, and controller interface align with your components.
- Mounting points and accessories: Check for rack mounts, fender bosses, and bottle cage bosses if you plan to add carriers or storage, as well as brake and derailleur clearance for a smooth drivetrain setup.
- Safety certifications and warranties: Look for third-party safety testing for electrical components and frame integrity, plus warranty terms on frame and paint finish to minimize post-purchase risk.
- Maintenance and upgrade trajectory: Consider how easy it is to replace components, service bearings, and update braking or suspension systems as your build evolves.
- Compatibility with existing parts: Match frame geometry to your preferred cockpit size, stem length, seat post, and saddle to ensure comfortable riding and precise handling.