Many people who plan to make their bicycle electric begin with a hub motor kit. Hub motor kits tend to be less expensive, easier to build, and don't require users to deal with gears. However, once you reach a steep incline or need to maintain speed on rough terrain, you'll understand why mid-drives exist.
Mid-drives offer improved performance and reliability. Bafang's new BBS02B mid drive conversion kit, which features CAN bus communication, provides more programming flexibility and allows for the use of 36V, 48V, and 52V battery configurations within a single unit. In addition, the BBS02B is compatible with the BBS-HD (Heavy Duty) mounting hardware which enables the use of a larger variety of frame sizes than previous BBS02B models.
Specifications and Build
The BBS02B utilizes a Brushless Geared Mid-Drive motor that will replace your bike's Bottom Bracket and Crank Set. Your bike's existing drivetrain chain, cassette, and derailleur will transmit the motor's power.
That is the purpose of Mid-Drives. They allow you to utilize your Gears to Multiply Torque. Therefore, Mid-Drives are ideal for those looking to conquer steep Hills and Off-Road terrain, especially when compared to similar Wattage Hub Motors.
Some key specifications for this kit:
- Motor Power: 1000 Watts (Peak Output Varies Depending on Battery Voltage and Controller Settings)
- Battery Compatibility: 36V, 48V, 52V Compatible Without Swapping Components
- Controller: Integrated CAN Bus Controller With Field Oriented Control Technology Provides Smooth Power Delivery
- Display Options: Typically Ships w/ C965 Or Similar LCD Display (Please Verify Listing For Specific Package)
- BB Shell Size: Standard Bafang BBS02B Mounting Fits BB Shells 68mm - 120mm
- Throttle Type: Half-Twist Throttle Included. Pedal Assist Sensor Included in Some Kits
- PAS Type: Cadence Based (Standard For BBS Family). No Torque Sensor
- Water Resistance Rating: IP54. Rain Resistant. Not Waterproof
The CAN Bus Controller represents a significant update to the BBS02 line. The older BBS02 motors communicated via UART while the CAN Bus controller utilizes the more modern CAN Bus standard. The advantages of using the CAN Bus controller are: it handles data faster than UART controllers and it provides smarter battery management. Additionally, utilizing the CAN Bus controller offers additional programming options that were previously unavailable via UART controllers.
Quality of construction on the BBS02B is very good. The motor case is cast aluminum with a textured black finish. The planetary gear reduction utilizes a nylon gear that is replaceable when it finally wears out. Pre-wired cables feature water resistant connectors. The total weight of the kit ranges from approximately 8 to 10 lbs., depending upon which specific kit variant was ordered. While not extremely lightweight, the weight distribution is centered low in the frame. When climbing a steep grade or trying to maintain speed on loose dirt roads, the motor feels like it is working with you because it is powered by your gears. Check price on Amazon.
Performance and Power
When comparing a 1000 Watt Mid-Drive on a 30 to 40 pound bicycle to a 1000 Watt Hub Motor on a 50 to 60 pound bicycle, you will quickly realize why mid-drives exist. The weight is centered low in the frame allowing for more stable and natural climbing action due to the fact that the motor is using your gears instead of pushing directly against the wheel as in a hub motor.
Using the CAN Bus programming capabilities on the BBS02B provides you with several ways to adjust the power delivery characteristics of your motor. One of the primary reasons people select Bafang over cheaper alternatives is the ability to program the controller using these options. Specifically, you can adjust: current limits, pedal assist levels, maximum wheel speed limit, throttle response curve, and even soft startup.
While there are additional parameters available for adjustment with the CAN Bus version compared to the UART version, primarily related to interpreting battery data from Smart Batteries (via BMS) that communicate with CAN Bus enabled displays.
In practice, the motor produces strong acceleration from a standstill. Due to field oriented control technology, the power delivery is linear and smooth. There is no abrupt surge of energy when accelerating from a standstill. See the BBS02B on Amazon.
On a 48V battery with a standard 25A controller limiting current, you can expect 30+mph flat out top speed on pavement with a normal rider. Jumping to a 52V battery will yield slightly increased top end speed as well as more pronounced mid-range torque.
An issue experienced by many of the early adopters of CAN Bus equipped BBS02B units: requires a specialized CAN Bus Programming Cable. Bafang sells the required programming cable separately. If you enjoy tweaking settings, add that cost to your overall investment.
The heat dissipation provided by this unit is adequate for a mid-drive in this power class. Prolonged operation at full throttle climbing on a hot day will eventually cause thermal rollback due to excessive temperature increase. However, most riders will not encounter such conditions except possibly during prolonged operations on extreme grades exceeding one mile.
Amazon Review Feedback
As this unit begins to gain traction among consumers on Amazon, customer feedback mirrors previous experiences reported by past purchasers of BBS02 units. As expected, early reviews are fewer in number as this product is relatively new compared to its predecessors (e.g. BBS02 and BBSHD). However, consumer sentiment regarding this unit appears consistent across prior generations of products.
Consumer benefits of the CAN Bus Tunability have been repeated throughout multiple reviews. Many reviewers have stated they appreciated the additional tunability capabilities offered by CAN Bus compared to their older BBS02 units. Consumers have consistently praised the throttle responsiveness exhibited by this unit. Several reviewers have commented favorably on both the build quality of this unit as well as the reputation associated with purchasing a BAFANG branded product.
The majority of complaints have been regarding the necessity of a separate programming cable specifically designed for CAN Bus applications. Numerous reviewers purchased this kit anticipating they could utilize their existing BAFANG programming cable with limited success. Minimal documentation accompanying installation process compared to older generations has resulted in some user frustration.
Multiple reviewers noted that installing this unit took substantially less time than anticipated (typically under 4 hours) assuming no extensive modifications or clearance issues existed with respect to the frame. A few reviewers indicated minor difficulties removing their bottom brackets and/or fitting parts due to tight chainstays on certain frames requiring filing down.
To view information regarding how this unit compares to other ebike conversion options, please refer to our ebike conversion kits overview article which details various types of ebike conversion kits available.
Who Will Benefit From This Unit
The BAFANG BBS02B is intended for individuals seeking greater capability than that offered by traditional hub motor conversions. Individuals desiring enhanced performance and reliability may benefit from this unit including: commuters and tourists, trail and off-road enthusiasts, and individuals utilizing cargo and utility bicycles.
Specifically suitable for:
Tourists and commuters: Utilizing mid-drive efficiency combined with either a 48V or 52V battery will provide ample range for everyday commuting. Additionally, due to programmable profiles utilizing conservative pedal-assisted modes, you can reduce battery usage during long tours.
Trail and Off-Road Enthusiasts: Trail riders prefer using their gears to remain within their mid-drive operating efficiency band during climbs. Hence they prefer mid-drives. Furthermore, the CAN bus based profiles provide superior low speed control during technical climbs compared to UART versions.
Utility and Cargo Bike Riders: Pulling children and groceries up steep grades using hub motors can be agonizing. The BBS02B in conjunction with an appropriate gearing combination can produce force equivalent to pulling ten times its own weight. Couple with a large capacity 52V battery from our ebike battery list for optimal performance while hauling heavy loads.
Individuals who should avoid investing in this unit: If your bike has a press-in bottom bracket or an uncommonly sized shell diameter, verify compatibility beforehand. Similarly, if you don't wish to learn how to configure or program your system or simply desire ease-of-use in terms of adjusting settings, then skip this unit. Default values will function properly but you will likely miss opportunities for enhancing your performance.
Find today's price and availability on Amazon here.
Frequently Asked Questions
Is the BBS02B compatible with my older BBS02 mounting hardware?
Yes. The BBS02B utilizes identical bottom bracket mounting brackets and lock rings as both the original BBS02 and BBSHD models. Thus, if you currently possess a BAFANG mid-drive installed on your bike, you will be able to bolt-on the BBS02B without having to purchase additional mounting hardware. Although the motor housing design is slightly different than earlier models (the housing is thicker), you may still have issues clearing tight areas on certain frames.
Do I need a special battery for my CAN Bus controller?
Any 36V, 48V or 52V battery will work with the BBS02B regardless whether your battery is smart or not. The CAN Bus controller communicates with smart batteries capable of communicating via CAN Bus. However it defaults back to standard voltage detection methods if your battery does not have CAN Bus communications support. Thus, if you are running an old 48V downtube battery it will still work fine, although you will miss out on any advanced battery information presented via your display.
Can I use a 52V battery with my 36V compatible model?
Be sure to check which model you are purchasing as there are multiple voltage combinations represented in listings. The 48V and 52V versions are fully compatible with 52V while the 36V version may employ lower capacitance ratings on internal capacitors within the controller. Therefore running a 52V battery through a controller rated for only 36V may result in damaged capacitors. Be sure to purchase only the correct voltage range specified for each individual unit type.
Which tools do I need for installation?
You will need: Bottom Bracket Removal Tool (matching your bike's bottom bracket standard), Crank Puller, Pedal Wrench, Allen Keys ranging from 4mm thru 8mm. Recommended: Torque Wrench for lock ring. Installation typically takes anywhere from two to four hours on average depending upon difficulty encountered during installation process such as removal of bottom bracket or clearance issues on certain frames.
Does the kit include a battery?
No. The BBS02B is merely a motor kit containing: motor unit itself, controller module, display module, wired harnesses connecting modules together, throttle assembly, pedal assist sensor assembly (if applicable), mounting hardware (frame clamps, bolts, etc.), and brake lever sensor assemblies (if included). All necessary components excluding battery must be sourced externally. Order the BBS02B kit on Amazon.
How loud is the BBS02B compared to hub motors?
The planetary gear reduction produces a whine under load that is louder than a direct drive hub motor but quieter than most geared hub motors. At cruise speeds around 20 mph with pedal assist engaged, the motor is barely audible. Under full throttle on a steep climb the gear whine becomes noticeable but remains unobtrusive. Many owners actually appreciate the audible feedback as it confirms the motor is under load.
For more mid-drive conversion options and battery pairings, browse our full ebike conversion kit selection or compare battery prices in our battery comparison table.