Technical Specs & Ratings





Class 1


Full Suspension



Hydraulic Disc



750 Wh

750 Wh

60.9 lbs / 27.65 kgs




Full Suspension


SR Suntour TRIAir 3CR Air Suspension, 150 mm Travel, 80% Lockout Lever, Rebound Clicker, Black Anodized Stanchion, Boost 148 mm Hub Spacing, 12 mm Thru-Axle with 6 mm Hex Bolt

SR Suntour Duralux 36 RC2 Air Suspension, 150 mm Travel, Compression Clicker, Rebound Adjust, 36 mm Black Anodized Stanchions, Boost 110 mm Hub Spacing, 15 mm Thru-Axle with Quick Release

Ryde Disc 30, Double Wall, Aluminum Alloy, ETRTO 622x30c, 30 mm Outer Width, 32 Hole, Tubeless Ready | Hub: Shimano HB-MT400-B

Front: Schwalbe Magic Mary Evo Super Gravity, 29" x 2.6" (66-622) 17 to 38 PSI, 1.2 to 2.6 BAR ADDIX Soft, TL-Easy, EVO Super Gravity, Back: Schwalbe Big Betty Evo, 27.5" x 2.6" (66-584) 45 PSI, 3.0 BAR, ADDIX Soft, TL-Easy, EVO, Tubeless Ready


Internal, Sealed Cartridge, Tapered 1-1/8" to 1-1/2"

Aluminum Alloy, 50 mm or 70 mm Length, 7-Degree Rise, MonkeyLink Magnetic Interface, 31.8 mm Clamp Diameter, Two 10 mm Spacers

BULLS Branded MTB, Aluminum Alloy, Double Butted, Low-Rise, 760 mm Length, 25 mm Rise, 9° Back Sweep

Bulls Branded Velo, Flat Rubber, Inner Lock Ring

Limotech Alpha 1 Dropper (100 mm or 125 mm or 150 mm Travel)


BULLS Branded Selle Royal

BULLS Branded Wellgo ZZE-01M, Plastic MTB Platform

Hydraulic Disc

Shimano BRM6120 Hydraulic Disc with 203 mm Rotors, Quad Piston Caliper, Two-Finger Levers with Adjustable Reach

Ebike Systems

Class 1


Bosch Performance Line CX (The Smart System)


Bosch LED Remote, Buttons: Power, Left/Right, +, -, Select, Lights if Available: Hold + Button, Walk Mode: Hold - Button

Bosch eBike Flow App

750 Wh

750 Wh

Bosch PowerTube 750 36 Volt, Lithium-ion, 20.1 Amp Hrs, 9.4 lbs, (Battery Shield Weighs 0.4lbs)

Bosch BPC3410 1.6 lb 36 Volt 4 Amp Charger

More Details

Trail, Mountain

United States, Canada

2 Years Motor and Battery, 5 Years Frame

9.4 (Battery Shield Weighs 0.4lbs)

6.39 lbs (2.89 kg)

16.14 in (40.99 cm)17.32 in (43.99 cm)18.89 in (47.98 cm)21.25 in (53.97 cm)

Medium 44cm: 17.5" Seat Tube, 23.25" Top Tube, 17.5" Reach, 30.25" Stand Over Height, 34.5" Minimum Saddle Height, 30.25" Width, 49.5" Wheelbase, 78.5" Length

Metallic Orange with Black Accents

SR Suntour TRIAir 3CR Air Suspension, 150mm Travel, 80% Lockout Lever, Rebound Clicker, Black Anodized Stanchion, Boost 148mm Hub Spacing, 12mm Thru-Axle with 6mm Hex Bolt

Bottle Cage Mount on Downtube, MonkeyLink Bracket on Stem and Seat Collar for Lights or Fender

Plastic Slap Guard, SP Connect Stem Cap Phone Mount, MonkeyLink Magnetic Reflectors, Plastic Mudguard on Fork Arch, Optional MonkeyLink Front and Rear Lights and Fender (Magnetic Connection, Lights Powered by Ebike Battery), Optional Bosch Kiox 300 Color LCD Display Panel

Locking Removable Downtube-Integrated Battery Pack with LED Charge Level Indicator, Bosch BPC3410 1.6lb 36 Volt 4 Amp Charger Smart System, ABUS Plus Code Keys, Maximum Cadence > 120 RPM Motor Support, Shimano CNM6100 Chain, The Tires Come with Tubes

Optional Bosch eBike Flow Smartphone App for iOS or Android with Motor Power and Speed Adjustment, Route Mapping and Ride History, User Profile, Connected Services (Apple Health, Strava), and Software Updates, USB-C Port on Bottom Edge of LED Remote for Diagnostics and Software Updates Only (5V 600mA)

Bosch LED Remote Readouts: Ambient Light Sensor on Top Edge, Charge Level Indicator (5 Blocks, 2 LED Colors: Blue is Full, White is Half-Full), Anti-Lock Brake System Indicator (Optional Hardware Required), Assistance Level (4 Colors Corresponding to ECO Green, TOUR+ Blue, eMTB Purple, and TURBO Red)

Advanced Pedal Assist, (Measures Rear Wheel Speed, Pedal Cadence, and Pedal Torque over 1,000x Per Second, Power Output Relative to Pedal Input: ECO 60%, TOUR+ 60%-340%, eMTB 140%-340%, TURBO 340%)

20 mph (32 kph)

Video Reviews

Written Reviews

This review was provided for free using a demo bike. My goal is to be transparent and unbiased with you, this video and writeup are not meant to be an endorsement of BULLS products. I welcome your corrections, additions, and feedback in the comments below, and the BULLS electric bike forums.


  • The bike is purpose built with good weight distribution, although it is fairly heavy due to the high capacity battery pack, long travel suspension, and plus sized tires. It comes in four frame sizes, one color scheme, and is generally sold through dealers.
  • The wheels and tires are different sizes, the front is larger than the rear. This is called a mullet, named after the hair style, because the larger wheel in the front handles the “business” of drops and large obstacles while the rear offers a “party” being more playful and quicker. You get a lower attack angle up front, raised bottom bracket, and sturdier rear wheel. Steering is a bit slower and smoother than if both wheels were 27.5″ vs. the front being 29″ so you can take on obstacles vs. steering around them.
  • Boost hub spacing means wider hubs that improve spoke bracing angle. Both wheels attach with sturdy thru-axles, 15mm in the front and 12mm in the rear. The tires are 2.6″ wide which is the narrowest “plus” size, offering improved stability, float, and overall forgiveness… supporting the “go over and off vs. around” capabilities of the bike.


  • Excellent two year warranty from Bosch, their hardware is UL certified, highly water and dust resistant, and I was told that they provide support on retired products for 10 years. BULLS offers a 5 year warranty on the frame, and the Shimano XTR groupset has a 3 year warranty.
  • BULLS is a large company with a good reputation, they sell through dealers who can help with fitting and service (over 200 independent electric bike shops in the USA), their products are sold internationally including Europe and North America.
  • The COPPERHEAD EVO AM 4 750 comes in four frame sizes, which improves rider fit. You get better comfort and handling this way, and the sizing extends to components like the seat post dropper and handlebar.
  • Purpose built frame with internally routed cables, sloped top tube for safer dismounts, drive system weight is kept low and center, the battery is completely hidden and well protected.
  • I love that they included a kickstand mount on the left rear chain stay, and it’s not a tab that hangs down. BULLS used industry standard two-hole threaded 18mm spaced interface. I also love the bottle cage mount on the downtube, the magnetic MonkeyLink reflectors, and where they positioned the battery lock and charging port; high up on the downtube, near the steer tube.
  • There are two magnetic light mounts with MonkeyLink interface, so you can add a headlight and a rear light or fender with light that will run off of the main rechargeable battery pack. The headlight is very nice with a flattened beam that won’t shine up into oncoming traffic and offers adjustable angle for aiming.
  • The battery pack locks into the frame using an ABUS locking core with XPLUS Code keys that can be matched to ABUS locks (like folding locks, u-locks, and frame locks), so you don’t need multiple keys! They seem to be high quality locks in general that would be more more difficult to defeat. The Bosch eBike Flow smartphone app also has a disable feature, where the bike won’t operate unless the smartphone enters the geofence around the bike.
  • The battery is very high capacity, offering 36 volts and 21 amp hours for roughly 750 watt hours of capacity. That means you can use higher assist levels without range anxiety, and just go farther in general.
  • Outstanding battery charger that’s relatively light weight at 1.6lbs, compact with removable wall-side plug, and puts out 36 volt 4 amps verses just 2 amps on many competing chargers. It has a sturdy plug design that works with the battery as well as the plug port on the bike.
  • This is a rare setup, stock mullet with 29″ wheel in the front and 27.5″ wheel in the back. They configured the geometry, so you don’t have to convert a 27.5″ setup with a new fork. This configuration blends stability and confidence where the front wheel rolls over obstacles easily and the rear wheel is lighter, quicker, and more nimble.
  • Another benefit of the mullet setup is higher bottom bracket clearance because of the taller front wheel, BULLS accentuates this by stocking shorter 165mm crank arms vs. 170mm to reduce pedal strikes.
  • Tire tread is different for each wheel, the front tire has more space between knobs to improve steering grab while the rear is tighter for improved traction during acceleration. The plus sized 2.6″ width improves stability, float, and comfort with a good range of PSI options. Rims and tires are tubeless ready to run at lower pressure and save some weight. I believe the rubber material used for the tires is the softest that ADDIX makes.
  • Large 203mm hydraulic disc brakes offer a good mechanical advantage for continuous descents and control over the larger 29″ front wheel. The wheels are heavier given the wider 2.6″ plus sized tires. Larger rotors also cool faster, and the front caliper uses quad piston with a larger brake pad surface.
  • Decent resin platform pedals from Wellgo, comfortable saddle, and locking Velo grips. The touch points are BULLS branded to look great, but come from reputable manufacturers.
  • Limoteq dropper seat post offers different travel depending on frame size. The adjustments are infinite, meaning you can dial it in more precisely vs. the older stepped dropper designs.
  • Solid drivetrain with 34 tooth sturdy steel chainring that has a narrow-wide tooth pattern for improved grab. Plastic chain guide ensures you won’t have drops, and it should clear some debris and mud as well. The 12-speed 10-51 tooth cassette provides excellent range for steep climbs and comfortable pedaling at speed during descents. I love the Shimano derailleurs with the locking clutch mechanism to reduce chain bounce, and appreciate the heavy duty rubber slap guard that will protect the fancy paint here.
  • The Shimano XTR trigger shifter allows you to shift down four steps at once using the long lever. The short lever can be actuated by pushing or pulling. It’s an excellent interface that is sturdy and comfortable.
  • Long travel 150mm air suspension with top shelf SR Suntour shocks front and rear. Both offer rebound and compression adjust; the front has low and high speed compression dials! The tapered steer tube supports a wide range of upgrade options if you wish to change hardware at any point in the future.
  • I was told that Bulls does not use the official split-pivot rear suspension design, but it looks very close and provides the same sort of isolation and vertical travel vs. an arched movement which can change your chain tension and produce kickback… whatever it is, it worked well during my test rides.
  • Bosch LED remote is easy to reach with your left thumb, the buttons are consistent and satisfying. The 5 LED lights actually communicate 10% charge level increments for more precise readings (blue is 20% chunk and white is 10% chunk). The four assist levels are matched to colors, so you don’t need to read anything, just memorize the colors Green = Eco, Blue = Tour+, Purple = eMTB, Red = Turbo. Eco and Turbo can be adjusted with the app, so their profiles match your ride style, you can even adjust the top speed of the bike from 20mph (32km/h) or below.
  • You could easily wire in the Bosch Kiox 300 or 500 LCD display panel for more precise battery readouts, current speed, trip distance, heart rate, range estimate and more… if you are willing to buy and upgrade. The free Bosch Flow smartphone app offers many of the same readouts and lets your phone act as a display in Ride Mode. Note that BULLS has a special smartphone case that can interface with the stem cap, so your phone would be perfectly mounted to read while riding.
  • I love that the Bosch Flow ebike app offers trip planning with GPS and gives you three options for direct, casual, or mountain. It dynamically updates your route depending on your ride preferences! It also lets you adjust Eco and Turbo assist settings (power output, acceleration, top speed, max torque). You can update your own firmware without visiting a shop, track rides, and connect to other cycling apps like Strava, Komoot, Apple Health, and Apple Watch.
  • The Tour+ and eMTB assist settings allow you to focus on the ride and gears. They dynamically provide more power based on how hard you’re pedaling. Think of Tour+ as the efficient dynamic setting and eMTB as the more power hungry high torque dynamic setting.
  • The Bosch Performance Line CX motor is super smart, measuring rear wheel speed, pedal cadence, and pedal torque over 1,000 per second! It’s extremely responsive and quick, is quieter than I remember, doesn’t weigh a lot at just 6.4lbs because of the magnesium housing, and supports over 120 RPM pedal cadence. That means you don’t have to adjust your pedaling or ride style to the bike, it adapts to you… and even provided shift detection to reduce wear on the chain and sprockets.
  • BULLS has integrated the magnet for measuring rear wheel speed into the disc brake rotor mount, so your wheel can stay more balanced! Spokes won’t get loose, and the magnet itself won’t get spun out of place or dirty as easily… which results in fewer read errors.


  • Due in part to the long travel suspension, wider Boost hub spacing with thicker thru-axles and associated frame materials, and high capacity 9.4lb Bosch PowerTube 750 battery pack, the bike weighs 60.9lbs which I consider heavy for a high performance all mountain ebike.
  • The battery cover seated well and provides good protection from dust and water, but it doesn’t lock to the frame. I feel that it could be easier to lose or have taken off, but at least it’s probably affordable and easy to replace because it’s just black plastic… and it’s not as heavy as a metal shield that some other ebikes use.
  • When mounting the battery back onto the frame, you have to actively twist the key to unlock the latch or the pack won’t slide in. It requires two hands and just isn’t as convenient as a ramped latch that I’ve see on other interfaces where you just push, especially because the battery is so heavy and long. At least the locking cylinder is on the right side of the downtube vs. the left, so it’s more accessible when the bike is laid on its side.
  • Be careful when lifting and transporting the PowerTube battery because it does not have an integrated handle like the PowerPack mid-frame and rear-rack models. I do appreciate how it clicks down one step when unlocking, before completely coming off the bike because you are less likely to drop it when removing.
  • The charge port is on the left side of the frame, which is the side you should lay the bike down to keep the derailleur from getting bent. So, it’s tricky to plug the bike in. At least the charge port is high up on the downtube vs. near the motor and crank arms. Note that the frame has an 18mm kickstand mounting point, which would make it easier to interact with and charge, but also rattle a lot when riding off-road.
  • None of the Bosch Smart System hardware is backwards compatible, so you can’t use a PowerTube 500 or 625 on this ebike, you cannot use the original Kiox, or other displays like Purion, Intuvia, or Nyon. At the time of this review, you could only use a smartphone with the Bosch eBike Flow app, or a Kiox 300 or Kiox 500.
  • I wish that the USB-C port on the Bosch LED remote was active for charging smartphones and other devices, especially since the Bosch Flow app has a ride mode that shows realtime stats and mapping. The bike has such a high capacity battery, and I love that it can run lights using the MonkeyLink interfaces… just wish it could do the same for other accessories.
  • If you aren’t using a smartphone as a display, the readouts on the Bosch LED remote are a bit limited. You get a battery charge level percentage with 10% steps (blue blocks represent 20% and white blocks represent 10%). Four colors communicate assist level… but there’s no current speed, min or max speed, range, cadence etc. that you could get from the Bosch Kiox 300 or Kiox 500 (which are sold separately).
  • The Bosch Performance Line CX Smart System motor is very responsive and powerful, but it uses energy faster and produces more noise than a lower powered variant, and some of the competition. It’s gotten a lot better, so this is more of a “high powered motors make noise” comment than a Bosch specific critique.
  • Only the front wheel offers quick release, the rear wheel uses a 6mm hex bolt, so you’ll need a tool to perform trail maintenance. There’s not toolkit built into the bike, connected to the axle, or stored under the stem cap like I’ve seen from other companies, so make sure you have a little tool kit with you.

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