Copperhead EVO AM 1 750

1 review for Copperhead EVO AM 1 750

1. 

   CC E-Cycles – April 21, 2023

   Video Review

   ---

   Written Review

   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.

   Observations:

   • The bike is purpose built with good weight distribution, although it is fairly heavy due to the high capacity battery pack. 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 the spoke bracing angle is sturdier and the frame is wider. Both wheels attach with sturdy thru-axles. 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.

   Pros:

   • 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 is a large company with a good reputation, they sell through dealers who can help with fitting and service, their products are sold internationally including Europe and North America.
   • The COPPERHEAD EVO AM 1 750 comes in four frame sizes, which improves rider fit. You get better comfort and handling this way.
   • 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 (it comes with magnetic MonkeyLink adapter), and where they positioned the battery lock and charging port (high up on the downtube, near the steer tube).
   • 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 battery is very high capacity, offering 36 volts, 21 amp hours, and 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 vs. just 2 amps on many competing chargers. It has a sturdy plug design that works directly to the battery as well as the plug port on the bike. It’s also UL certified.
   • 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.
   • Clean aesthetic with satin black paint on the frame, fork lowers, rims, spokes, posts, and handlebar. Notice the brown sidewalls on both tires, despite being different sizes and tread patterns.
   • 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. The configuration blends stability and confidence on bigger drops and hits with playfulness and precision.
   • 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.
   • 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.
   • 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.
   • Decent resin platform pedals from Wellgo, comfortable Selle Royal 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 demo bike I reviewed did not have the dropper installed… but I’m told it offers a bit of cushion as well as height adjustment. Expect a plastic dropper lever within reach of the left grip.
   • 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, even on the roughest terrain. The 10-speed 11-46 tooth cassette provides enough range for steep climbs and comfortable pedaling at speed.
   • Long travel 150mm air suspension with decent SR Suntour shocks. Both offer compression lockout (the rear says 80% lockout) and rebound adjust. They seem less adjustable and smooth to me, but weren’t dialed in perfectly after other demo riders had used them. The tapered steer tube supports a wide range of upgrade options if you wish to go that route someday.
   • 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.
   • You could easily wire in the Bosch Kiox 300 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.
   • 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.

   Cons:

   • Due in part to the heavy steel stanchions on the suspension fork, wider Boost hub spacing and associated frame materials, and high capacity 9.4lb Bosch PowerTube 750 battery pack, the bike weighs 59.5lbs which I consider heavy for a high performance all mountain ebike.
   • The suspension shocks offer less refined compression adjustment, it’s more like open and 80% locked out. I felt that the fork was a little stiff vs. plush and smooth, even after removing some air pressure. It’s heavier than a fancier fork with aluminum alloy stanchions.
   • 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.
     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 (which is 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 seat tube collar and front wheel offer 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.
   • I didn’t see a slap guard on the right chain stay, and I did see a lot of chips from the chain bouncing around and making contact with the frame. Consider using some clear box tape, or purchasing an aftermarket slap guard made from neoprene or rubber to keep things looking nice. The derailleur does have a clutch lever that can tighten the spring that helps reduce bounce and drops, so make sure it’s activated.
   • The battery seemed to rattle around a bit, perhaps the demo bike was pushed hard and the interface wasn’t tightened after the 100+ miles ridden by other people before I got it. Also, when mounting the battery back onto the frame, you have to actively twist the key to unlock the latch or the pack won’t go 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 heavy at 9.4lbs.
   • 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.
   • This is a minor thing, but the chainring doesn’t cycle backwards when you backpedal, this changes how drivetrain service is done… you basically need a bike maintenance stand or a friend to lift the bike and pedal to clean and lubricate the chain. One positive note here, is that Bosch has setup the bottom bracket with some resistance so the cranks won’t spin as freely backwards, which could lead to more shin scrapes and shin bumps if your foot slips off when pedaling.
   • 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.