Bulls Six50 Evo Am 4 Sram Electric Bike Review
Bulls Six50 Evo Am 4 Sram
Bulls Six50 Evo Am 4 Sram Bosch Performance Line Cx Motor
Bulls Six50 Evo Am 4 Sram Bosch Powertube 500 Battery
Bulls Six50 Evo Am 4 Sram Alloy Handle Bar Kiox Display
Bulls Six50 Evo Am 4 Sram Bosch Kiox Display
Bulls Six50 Evo Am 4 Sram Grips Kiox Button Pad
Bulls Six50 Evo Am 4 Sram Magura Carbotecture Brake Levers
Bulls Six50 Evo Am 4 Sram Bosch Cx Mid Drive Alloy Chainring Guard
Bulls Six50 Evo Am 4 Sram Fox Float Factory 36 Air Suspension Fork
Bulls Six50 Evo Am 4 Sram Monkeylink Bottle Adapter Downtube
Bulls Six50 Evo Am 4 Sram Xx1 Eagle 12 Speed Drivetrain
Bulls Six50 Evo Am 4 Sram Schwalbe Magic Marry Tires
Bulls Six50 Evo Am 4 Sram Bosch Powertube Battery Pack For Ebikes
Bulls Six50 Evo Am 4 Sram Powertube Battery Removed Custom Alloy Shield
Bulls Six50 Evo Am 4 Sram Bosch Ebike Charger
Bulls Six50 Evo Am 4 Sram Stock
Bulls Six50 Evo Am 4 Sram Electric Bike Review
Bulls Six50 Evo Am 4 Sram
Bulls Six50 Evo Am 4 Sram Bosch Performance Line Cx Motor
Bulls Six50 Evo Am 4 Sram Bosch Powertube 500 Battery
Bulls Six50 Evo Am 4 Sram Alloy Handle Bar Kiox Display
Bulls Six50 Evo Am 4 Sram Bosch Kiox Display
Bulls Six50 Evo Am 4 Sram Grips Kiox Button Pad
Bulls Six50 Evo Am 4 Sram Magura Carbotecture Brake Levers
Bulls Six50 Evo Am 4 Sram Bosch Cx Mid Drive Alloy Chainring Guard
Bulls Six50 Evo Am 4 Sram Fox Float Factory 36 Air Suspension Fork
Bulls Six50 Evo Am 4 Sram Monkeylink Bottle Adapter Downtube
Bulls Six50 Evo Am 4 Sram Xx1 Eagle 12 Speed Drivetrain
Bulls Six50 Evo Am 4 Sram Schwalbe Magic Marry Tires
Bulls Six50 Evo Am 4 Sram Bosch Powertube Battery Pack For Ebikes
Bulls Six50 Evo Am 4 Sram Powertube Battery Removed Custom Alloy Shield
Bulls Six50 Evo Am 4 Sram Bosch Ebike Charger
Bulls Six50 Evo Am 4 Sram Stock


  • A premium all mountain electric bike with 150mm Fox air suspension, SRAM XX1 Eagle 12-speed drivetrain, Bosch Performance Line CX high-torque motor, and Magura MT7 hydraulic disc brakes with adjustable CARBOTeCTURe levers
  • Wider Boost hub spacing provides a stronger bracing angle for the spokes and additional room for high volume plus sized tires, thru-axles front and rear, Schwalbe Magic Mary tires offer puncture protection and come tubeless ready
  • Excellent weight distribution, stealthy integrated Bosch PowerPack 500 battery, optimized motor integration, available in three frame sizes through a growing network of dealers, new Kiox color display is removable and provides Micro-USB charging
  • Two pounds heavier than the prior year model but costs $500 more due to upgraded drivetrain and display, Bosch Performance motors utilize a reduction gear system which produces a bit of drag when unpowered, these motors also produce a bit more noise than some competitors like Brose

Video Review

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Body Position:


Suggested Use:

Trail, Mountain, Downhill

Electric Bike Class:

Pedal Assist (Class 1)
Learn more about Ebike classes


2 Years Motor and Battery, 5 Years Frame


United States, Canada

Model Year:


Bicycle Details

Total Weight:

54.4 lbs (24.67 kg)

Battery Weight:

6.3 lbs (2.85 kg) (7.2lbs with Alloy Shield)

Motor Weight:

8.8 lbs (3.99 kg)

Frame Material:

7005 Aluminium Alloy

Frame Sizes:

17.32 in (43.99 cm)19.29 in (48.99 cm)21.25 in (53.97 cm)

Geometry Measurements:

Medium 49cm Measurements: 19.5" Seat Tube, 23.5" Reach, 31" Stand Over Height, 37" Minimum Saddle Height, 31.25" Width, 77.5" Length

Frame Types:


Frame Colors:

Silver with Matt Black and Orange Accents

Frame Fork Details:

Fox Float Factory 36 Air Suspension with Kashima Coat, 150mm Travel, Compression Adjust (Open, Medium, Firm), Rebound Adjust, Boost 110mm Hub Spacing, 15mm Thru-Axle with Quick Release

Frame Rear Details:

Fox Float Factory with Dual Piston System (DPS) Air Suspension, 150mm Travel, Compression Adjust (1,2,3), Rebound Adjust, Boost 148mm Hub Spacing, 12mm Thru-Axle with 6mm Hex Bolts

Attachment Points:

MonkeyLink Magnetic MonkeyBottle Mount on Downtube

Gearing Details:

12 Speed 1x12 SRAM XX1 Eagle Derailleur, SRAM NX Eagle 11-50 Tooth Cassette

Shifter Details:

SRAM GX Triggers on Right


Miranda Delta Boost, Alloy, 165mm Length, 16 Tooth Chainring with Alloy Guard


Wellgo ZZE-01M Alloy Platform, Cage Style


FSA Orbit 1.5 ZS, Sealed Cartridge, Threadless, Internal Cups, Tapered 1-1/8" to 1-1/2"


MonkeyLink Mangnetic Interface, Alloy, 55mm Length, 0-Degree Rise, Two 10mm Spacer, One 5mm Spacer


Bulls Branded, Alloy, Low-Rise, 760mm Length, 15mm Rise, 9-Degree Bend, 31.8mm Bore

Brake Details:

Magura MT7 Hydraulic Disc with 203mm Rotor in Front and 180mm Rotor in Back, Quad-Piston Calipers, Two-Finger MT7 CARBOTeCTURe Levers with Shiftmix 3 Clamp and Tool-Free Reach Adjustment and Tool Free Free Stroke Adjustment


Ergon GD1 Factory Frozen, Flat Rubber, Locking


Fizik Gobi M7

Seat Post:

Kind Shock Lev SI Dropper (100mm, 125mm, or 150mm Travel)

Seat Post Length:

250 mm

Seat Post Diameter:

30.9 mm


DT Swiss H 1700 SPLINE, Double Wall, Alloy, 35mm Inner Width, 32 Hole


Stainless Steel, 14 Gauge, Straight Pull, Black with Nipples

Tire Brand:

Schwalbe Magic Mary, 27.5" x 2.6" (65-584)

Wheel Sizes:

27.5 in (69.85cm)

Tire Details:

17 to 35 PSI, 1.2 to 2.6 BAR, ADDIX Speedgrip, EVO Evolution, APX Reinforced, TLE Snakeskin

Tube Details:

Presta Valve


Plastic Velo Chainstay Protector, MonkeyLink Magnetic Interface for Front and Back Lights, Optional Monkey Link Lights Combo Pack (100 Lux, $170), Optional Monkey Link Water Bottle ($46)


Locking Removable Downtube-Integrated Battery Pack, 1.7b lb 4 Amp Charger, Maximum 120 RPM Motor Support, 20mm Kickstand Mounting Point, ABUS Plus Locking Core and Keys (Keyed-Alike Code Card)

Electronic Details

Motor Brand:

Bosch Performance Line CX

Motor Type:

Mid-Mounted Geared Motor
Learn more about Ebike motors

Motor Nominal Output:

250 watts

Motor Peak Output:

600 watts

Motor Torque:

75 Newton meters

Battery Voltage:

36 volts

Battery Amp Hours:

13.4 ah

Battery Watt Hours:

482.4 wh

Battery Chemistry:


Charge Time:

4.5 hours

Estimated Min Range:

30 miles (48 km)

Estimated Max Range:

85 miles (137 km)

Display Type:

Bosch Kiox, Removable, Magnetically Attached, 1.9" Transmissive Backlit Color Display, Automatically Adapts to Lighting Conditions, Buttons: Power, Lights


Clock, Assist Level (Off/Gray, Eco/Blue, Tour/Green, Sport/Yellow, Turbo/Red), Light Icon, Batter (Percentage and Infographic), Units (MPH or KM/H), Current Speed, Power Meter Infographic (Shows Rider Input and Motor Input), Range Estimator, Trip Distance, Trip Time, Power (Watts), Cadence (RPM), Average Speed, Max Speed, Heart Rate, Double Battery Readout, Settings

Display Accessories:

Independent Button Pad on Left, Buttons: Walk Mode, +, -, Left, Right, Select, 5 Volt 500mA Micro-USB Port on Lower Edge of Display, (Navigate to Settings with Left Arrow then Click Select Button)

Drive Mode:

Advanced Pedal Assist (Measures Wheel Speed, Pedal Cadence and Pedal Torque, Over 1,000 Readings Per Second, Power Output Relative to Pedal Input: Eco 50% 40 Nm, Tour 120% 50 Nm, eMTB 120% to 300% 75Nm, Turbo 300% 75Nm)

Top Speed:

20 mph (32 kph)

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Written Review

To run the forums, host the website, and travel, I charge a universal service fee for my reviews. This in-depth review was sponsored by BULLS North America. My goal is to be transparent and unbiased, this video and written review are not meant to be an endorsement of BULLS products.

The BULLS SIX50 EVO AM 4 is an all-mountain electric bike running the proven Bosch CX motor and frame-integrated Bosch PowerPack 500. It’s well balanced and sturdy, featuring wider Boost hub spacing, thru-axles, and plus sized Schwalbe Magic Mary tires that reduce deflection, improve traction, and provide float for the heavier bike. Compared to the 2018 model, which used a Shimano drivetrain, the 2019 SIX50 EVO 4 SRAM is actually two pounds lighter, but still comes in at roughly 54.4lbs. Aside from the Fox Factory shocks, Magura MT7 hydraulic disc brakes with carbon fiber levers, SRAM EAGLE X11 12-speed drivetrain, and PowerTube batttery, one of the things that really differentiates this model from other leading products for 2019 is the color Bosch Kiox display panel. It’s exciting to see and experience the latest and greatest ebike hardware from a leading brand with a growing network of shops in North America. Bulls has been selling in the USA since 2016 and their independent bicycle dealers provide ongoing service and warranty support. The SIX50 EVO AM 4 comes in three frame sizes, which are great to experience in person, and you’ll notice the sloped top tube for more comfortable standover. Furthermore, I really appreciate dropper seat posts that don’t have pre-set positions. The Kind Shock LEV SI dropper comes in three lengths to accommodate the three different frame sizes. Also, while many competing full suspension ebikes struggle to fit on bottle cage bosses, BULLS has gone above and beyond with the magnetic MonkeyLink downtube mount and two wired-in MonkeyLink light interfaces. The stem and seat post clamp work with a whole range of accessories, including a rear fender option. The headlight design is not aimable and the dual-light pack costs $170, which is a bit high in my opinion, but they’re very functional and easy to remove for weight savings if you know you’ll be back before the sun goes down. In short, you’re getting an extremely rugged, capable, and beautiful electric bike here. Bulls offers a specced-down model called the EVO AM 3 for people who want to save some coin and are okay with RockShox suspension and a Shimano XT drivetrain. I actually prefer the trigger shifters from Shimano because the high lever moves in both directions (forward or back), and the low lever can do multi shifting. Shimano also offers a one-way clutch feature on their derailleur… which is what we saw with the 2018 SIX50 EVO AM 4, it had Shimano XTR. SRAM has their own roller clutch feature to make rear wheel maintenance easier, and the derailleur shifts quick and clean, I’m just more used to Shimano. Anyway, the EVO AM 3 uses the same battery setup and motor as the AM 4 but comes in dark grey and neon green vs. the exposed silver Aluminum here.

Driving this ebike is a powerful mid-motor from Bosch called the Performance Line CX. It offers 350 to 570 watts of power output, and up to 75 Newton meters of torque depending on the level of assist being used. If you live in Europe, this system may be rated at 250 to 500 watts and limited to 25 km/h vs. 20 mph (32 km/h), but it still delivers high torque. The motor controller listens to rear wheel speed using a magnet and electronic sensor on the left chain stay, pedal cadence, and pedal torque signals, over 1,000 times per second. These signals allow it to start and stop almost instantly to keep you in control… which is especially important in a technical mountain setting. Beyond assistance, this motor controller is also listening for tension changes in the chain, resulting from gear shifting. When it senses these inputs, it tells the motor to ease off in order to reduce mashing and gear grinding. It’s not a perfect system, and you can help it by reducing force on the pedals yourself as you shift gears, but it’s something that only Bosch is really doing right now. There have been a few hardware driven shift detection designs over the years (from Impulse and Bafang partners) but the software solution that Bosch has developed is a real differentiator. I love how BULLS has angled the motor and tucked it up into the frame in order to maximize ground clearance and shorten the effective chain stay length for a snapper ride feel. Visually, the motor doesn’t blend into the frame as nicely as if it had a silver casing, but the neon orange aluminum skid plate does set off the fork sticker and label accents around the frame and tires. This motor spins a single chainring with 16 teeth (one more than the 15t chainring on the 2018 model), to maximize starting and climbing power while allowing for high top speeds. It balances the wider 11 to 50 tooth cassette perfectly and is roughly equivalent to a traditional 40 tooth chainring. The chainring spins at 2.5 revolutions for each crank revolution because the motor has a reduction gear to provide a mechanical advantage. I’m told that the smaller chainring increases chain grab but noticed that it can also bring the chain closer to the right chain stay and possibly allow for chain suck in very muddy environments. The Bosch Performance Line CX mid-drive unit is also the most power hungry and loudest of the Bosch lineup and it weighs a bit more at 8.8lbs. But again, that weight is positioned very low and centered along with the battery pack for optimal balance and stability. Expect reliability, great power, dynamic ride experiences with eMTB mode, and an increase in noise at high pedal rates. All Bosch Performance Line motors support pedal rates up to 120 RPM, which allow them to continue supporting you during massive downshifting, riding into a steep hill. For even more details and footage, check out my stand alone Bosch CX motor review in the EBR forums.

Powering the bike is a high capacity Bosch PowerTube 500 battery which offers 36 volts and 13.4 amp hours for a total of 482.4 watt hours. Bosch has been supplying ebike batteries to North America since 2013 and is well known for reliability and cross compatibility between different brands. That’s less common now with the PowerTube, because there is a vertical mount and side mount option, and each manufacturer can opt for a custom interface and cover. BULLS has chosen a bottom-load design that’s easy to click in without needing a key but can be a little tricky to remove… their aluminum alloy covers look great, but add nearly a pound of weight and are color-matched so don’t look good if you swap between different bike models. As for the PowerTube battery, there’s no carry loop at the top or side, which means you have to use extra care connecting and disconnecting it from the frame. Iit still has a 5-LED battery indicator on the end (near the charging port) so you can quickly judge capacity even if you store it separately from the bike frame. I almost always take the pack off before lifting the bike for service or transport. The charging port of the battery is replicated on the left side of the bike frame, near the base of the downtube, so you can charge without removing the battery every time. The thing is, this port is located very near the left crank arm and I could imagine a snag or disconnect if you’re charging and bump the pedals… it also seemed like the protective rubber cap for this port didn’t seat as easily as some competing designs. The PowerTube battery pack requires a bit of extra flexibility and patience to remove from the frame. First, you have to insert the key and unlock it, then the pack sort of pops out (downwards) half an inch near the head tube. At this, point the pack is unlocked but it won’t come out completely. To fully release it, you have to press a little plastic button inside the crack, all while trying to balance the bike frame because there’s no kickstand. The left chain stay actually does have a 20mm kickstand mounting point if you wish to use it, but a stand would add weight rattle a round constantly in rough terrain. Anyway, I have relatively small fingers, so it wasn’t too difficult to remove the pack. Once you actually press the button, the pack is completely free at the top and will swing down towards the front tire. It weighs about 7.2lbs total, with the attached metal shield, so expect a bit of weight and please be careful not to drop the battery because they are like $900 to replace. Again, the PowerTube battery for BULLS doesn’t have a handle built in, and with the metal shield it weighs more than the older Powerpack… and, since it’s coming down vs. resting as you lift up, it just seems more precarious. Perhaps that is why Bosch encased the PowerTube itself in an Aluminum alloy box. As a side note, to best care for the lithium-ion cells that are packed inside the PowerTube, I have heard that you should avoid storing it in extreme heat or cold, and that you should leave it around 50% full for long periods of disuse vs. completely full or empty. Charging the pack is fast and easy with the included 4 amp Bosch charger. It is one of my favorite chargers because it is so compact and lightweight at ~1.7 lbs. You will probably have better luck sticking this charger into a backpack than trying to bring along a second PowerTube battery to extend range. Bosch does offer a compact travel charger that delivers 2 amps, but it’s only 0.5lbs lighter and just a little bit slimmer, so I’d probably just stick with the original. In conclusion, I feel that the PowerTube battery offers a mixed bag of benefits and trade-offs. It’s hidden, positioned low, doesn’t rattle, and offers a relatively high capacity, but is heavy and less easy to swap and use with a second pack because of the screwed-on shield design. For even more details and footage, check out my Bosch PowerTube review in the EBR forums.

One of the most noticeable changes for 2019 is the Bosch Kiox display panel vs. the Bosch Purion. This thing has a color LCD, Gorilla glass screen, active Micro-USB charging port, connects via magnets and is removable, but cannot be adjusted for glare because it mounts in a fixed position over the stem. In terms of actual use, the Kiox provides more detailed menu readouts; including 1% stepped battery percentage vs. a five-bar infographic with wider 20% steps. Its color readout provides a fast and comfortable way to interpret assist levels (grey for Off, blue for Eco, green for Tour, yellow/gold for Sport or eMTb, and red for Turbo). The screen on the Kiox is smaller than Intuvia, but the colors make it easier to interpret in many ways without having to squint and actually read. Because of how it’s mounted, my guess is that the Kiox may also take less damage if the bike tips or crashes. I think it’s actually designed to pop off vs. cracking the mounting bracket when taking direct hits. Interacting with the display involves some button clicking. You begin by charging and mounting the battery, then press the power button on the display unit. The Kiox has power and lights buttons positioned juste below the screen. Most interactions are done through a remote button pad which is mounted within reach of the left grip. This pad has a +, -, left, right, and select button, along with a walk mode button on the top edge. It boots up in the second view, showing your assist level with a swirling color infographic. different parts of the swirl line fill based on how much power you exert as a rider and how much power the motor exerts, when active. You can arrow left or right to change screen readouts, and I especially like the ones towards the right, which show a range estimate based on remaining battery capacity and the last mile of riding. Unfortunately, the Kiox requires you to click right or left to get through, and does not loop back to the start for convenience… and this requires more hand effort and time. Perhaps Bosch will update this in the future, because the Kiox does come with Bluetooth integration and will be able to connect to a smartphone app. For now, Bluetooth seems to be reserved for use with aftermarket heart rate monitors. I’m reviewing this product in North America, but Europe is a bit ahead with the release and apps. The two markets differ slightly and I’d recommend working with your local dealer to learn more and get help with software updates. Okay, all things considered, the Kiox is an excellent display units. It brings a lot of improvements over Purion and Intuvia while adding a touch to the price point. For more information and pictures of the Kiox, I’ve created a guide in the EBR forums here.

In closing, the SIX50 EVO AM 4 is a top-end enduro electric mountain bike with excellent suspension and some welcome refinements for 2019. I appreciate that they switched to ABUS locking core for the battery, because it comes with a keyed-alike card that lets you order matching lock accessories. The new Kiox display takes the compact size and durability of the Purion with the removability and functional Micro-USB charging port and deeper feedback of Intuvia. The new Magura MT7 brake levers offer tool free reach and throw adjust, which is something I rarely see, and the rear caliper now offers quad piston vs. dual piston before. This electric bike is comfortable, responsive, highly adjustable (with rebound, compression, and sag adjust on the shocks), and all of the suspension stanchions are anodized with the Fox Kashima coating to slide smoothly and be tough. I even like the grips that were chosen, but the Fizik saddle is a little round and hard for my taste and the pedals are just basic cages that can easily get bent and become sharp… so I’d replace those. As always, I welcome corrections and feedback in the comment section below and welcome you to post your own reviews, pictures, and make friends in the Bulls Ebike forums.


  • Totally custom frame with sleek motor integration to maximize ground clearance, hidden battery and integrated wires, three frame sizes to choose from so you can dial in fit and comfort (I reviewed the Medium 49cm)
  • The sloped top tube is designed to lower standover height and help you step off without racking yourself if the terrain is unstable or soft
  • Top-of-the-line suspension from Fox, the 150mm travel length is ideal for Trail and All-Mountain riding, wider 36mm suspension fork stanchions provide stiffness and strength to the fork which is important given the thicker 15mm thru-axle with wider Boost hub spacing and heavier plus sized tires, both shocks offer, rebound, compression (climb, trail, descend), and air pressure adjustments for different body weights and terrain
  • Boost hub spacing also provides a stronger bracing angle for the spokes, both wheels attach with sturdy thru-axles and the rims and tires come tubeless ready for easy conversion to save weight and ride with lower PSI
  • The suspension design resembles split-pivot which is great for isolating vertical movement and reducing chain kickback, it brakes well but suffers a bit from bob during climbs (so the compression adjustment on the rear shock is nice to have)
  • The frame comes stock with MonkeyLink light and fender attachment points, if you add lights to the stem and seat post clamp they will run off of the main battery pack which is convenient… the lights are quick and easy to remove to reduce weight and clutter if you’re not expecting to ride in the dark
  • I love the magnetic MonkeyLink bottle cage adapter on the downtube, it’s great to have fluids within reach and many competing electric mountain bikes (especially full suspension models) just don’t have room for this type of thing, for those who aren’t thrilled with the $46 bottle accessory, you can remove the magnetic dock and mount standard aftermarket parts (cages, folding lock, mini-pump etc.)
  • Great seat post dropper from Kind Shock, it comes in several lengths to match the bike frame size and allows you to adjust the height wherever you want vs. set intervals, I feel like this sort of accessory has become standard on higher priced all mountain and enduro electric bikes
  • Upgraded SRAM Eagle 12-speed drivetrain with enormous 11-50 tooth cassette vs. the older SIX50 EVO model which came with Shimano XTR 11-46 tooth cassette
  • Premium Magura MT7 hydraulic disc brakes with large 203mm front rotor offering leverage and cooling benefits, quad piston calipers provide maximum grab, CARBOTeCTURe levers reduce weight and offer adjustable reach and throw for different hand sizes and gloves vs. no gloves
  • I really like the Ergon GD1 Factory Frozen grips used on this bike and haven’t seen them on many other models, they are locking, have a rubber inner guard, a semi-ergonomic design, and rounded vs. flat for comfortable use with mountain biking gloves
  • The high volume Schwalbe Magic Mary tires offer excellent traction, reduced deflection off of rocks, float in soft terrain, and they are rated EVOLUTION which means “the very best possible made with high grade materials and the latest technology” you get TLE tubeless easy, and sturdy APX reinforced sidewalls
  • BULLS has added a little alloy guard to reduce pant leg contact with the chain and chainring, I love how compact they managed to make their motor casing, and appreciate the color matching and tough skid-plate below, there’s also a little shield protecting the stanchion on the rear shock so it won’t get dirty and chipped up over time
  • As with most high-end electric bicycles, all of the cables and wires are internally routed through the frame here, it looks nice and reduces the potential for snags
  • The frame comes with kickstand provisions towards the back of the left chain stay, if you do add one for urban riding, it shouldn’t get in the way while pedaling and won’t cause pedal lock, BULLS uses the Standwell SW-RA032J on their urban models like the ICONIC EVO TR 1
  • BULLS chose to build their battery lock design with an ABUS locking core, and they come with a little card that has a code on it so you can order matching locks and other accessories, this is a unique program that could help you reduce clutter on your keychain and order replacement keys more easily
  • Given the high-capacity Bosch PowerTube 500 battery, it’s nice that BULLS opted to include the faster four amp charger, it’s relatively lightweight at ~1.7lbs and fairly compact, so you can bring it along on rides to top off when taking a break
  • With the Bosch Performance Line CX motor you get access to very high torque output, up to 75 newton meters, and eMTB drive mode which dynamically responds to your pedaling for low and high power output without having to interact with the display, it’s based more on torque and was developed with input from pro mountain bike riders by Bosch, it works pretty well and feels natural
  • The Bosch motor controller is extremely smart and consistent, it measures rear wheel speed, pedal cadence, and pedal torque over 1,000 per second while also listening for pressure changes from shifting and then easing off, this protects the drivetrain a bit from mashing
  • Another great feature with Bosch Performance Line motors is that they can support higher pedal rates without fading out and losing power, you can reach 120 RPM (pedal strokes per minute) and the motor will still be there for you, this allows you to downshift when going into a hill without losing support
  • With all of the Bosch motors, there’s a shift detection software system built in that can sense that gears are being changed and it tries to ease off of the power to reduce strain on the drivetrain, it’s not perfect but it’s better than nothing and really comes in handy with a 12 speed drivetrain!
  • The bike has walk mode enabled, which is especially useful if you encounter a section of road or trail that you aren’t comfortable riding or maybe you get a flat tire, considering that the bike weighs ~60 lbs and has pannier racks for cargo, it could be really nice to get help moving it along in some situations
  • Battery and motor weight are kept low and center on the frame which improves stability and handling, with the main triangle section open on this electric bike, you can more easily lift it and hang it from some car and bus racks
  • The battery pack can be charged on or off the bike frame (for convenience, battery protection, and reduced weight for transport), I recommend storing lithium-ion battery packs in a cool dry location to keep the cells healthy, try not to store it below 50% over long periods
  • Unlike some other Bosch PowerTube battery implementations, this one can be forced into place without using the key to unlock the core, just push on it and listen for a click to know that it’s securely mounted
  • Not every electric bicycle company has mastered the design aesthetic of integrating the Bosch motor as well as BULLS has, in my opinion, look at how it’s angled up and incorporated into the seat tube and downtube to raise ground clearance, it really blends in compared to the big plastic housing used by many other companies
  • Interacting with the display is intuitive and simple enough that you really don’t have to look down that often once you get the hang of it, the button pad is positioned within reach of the left grip and produces a tactile click
  • I love that Kiox is color because it’s easy to interpret which assist level you’re in without squinting to read a small font, I love that it lists battery percentage in addition to range estimate for more precise trip planning, and I love that Bosch is working on Bluetooth applications which could sync with heart rate monitors and other devices in the future
  • The Kiox display is well protected at the center of the bar, is connected via magnets and can be removed easily, uses Gorilla Glass so it won’t scratch up like plastic, and it offers Micro-USB charging for portable electronics
  • Excellent two year warranty covers everything on the bike, including the motor, battery, and display system with a vast network of dealers in the US and other parts of the world who can help with fit and maintenance


  • This ebike is on the heavy side at 54.4lbs because it has wider Boost hub spacing, sturdy thru-axles, high volume tires, and the heavier Bosch PowerTube battery with alloy casing… but at least you can remove the battery to reduce that weight by roughly 7.2lbs and the front wheel has quick release, it’s actually ~2lbs lighter than the older SIX50 EVO because of the carbon brake levers, SRAM drivetrain, and other refinements
  • As with any premium electric bike with name brand components and a leading drive system that is custom-integrated into the frame, this ebike costs more money, but at least it is sold through dealers who can offer support and comes with a great 2+ year comprehensive warranty
  • The Bosch CX motor is responsive and powerful but also draws energy faster, produces more noise, and weighs a bit more than competing products like the Shimano STePs E8000 or Yamaha mid-drive
  • The Bosch Performance Line motors are heavier and larger than the Brose S, Shimano E8000, and Yamaha PW-X while also having a wider minimum Q-Factor (so the bottom bracket can be wider), but that’s not a huge issue given the wider Boost hub spacing and larger tires on this ebike
  • Because the motor uses reduction gearing system with a smaller 15 tooth chainring (which spins 2.5 revolutions for each crank revolution), you end up with some friction if the motor isn’t assisting, this adds just a touch of work… but the upside is that the smaller sprocket grabs the chain well and offers a mechanical advantage tot he motor
  • Minor gripe here, the front MonkeyLink connection point is fixed, so you cannot adjust the angle of the headlight as you can with many competing bolt-on lights from Busch & Müller, Supernova, Fuxon and others
  • The Powertube battery is not available in a smaller 400 watt hour configuration (that could reduce weight and cost less as a spare), it may be difficult to rent on location or to carry separately because of the long dimensions and extra shielding piece, it seems like you’d have to unscrew that from the original pack and re-attach to work with a second battery… it’s just not nearly as versatile as the older PowerPack batteries
  • The location of the battery charging port on the left side of the bike frame is pretty close to the left crank arm, and actually blocks the rotation path when plugged in, just be careful not to bump the pedals when the bike is plugged in, or consider charging the battery off the bike, the rubber cover protector for this port is also a bit finicky to get in (at least for me)
  • I’m not a huge fan of cage pedals like the ones included with the BULLS SIX50 EVO AM 4 because they don’t offer a lot of surface area and can easily bend and become sharp when laying the bike down on its side, consider swapping for some Wellgo alloy or magnesium platform pedals if you’re concerned about slipping off or have larger feet
  • I don’t like the SRAM trigger shifters as much as Shimano because they only offer a single step vs. multi-shift and both levers only go forward vs. two-way on the high lever from Shimano


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A high-speed, feature-complete, urban electric bike with fenders, front suspension fork, suspension seat post, integrated lights and a nice modern rack. Available in 5 sizes including high-step and mid-step frame styles with a gel saddle and…...

BULLS E-STREAM EVO AM 4 27.5+ Review

  • MSRP: $6,299
  • MODEL YEAR: 2019

A full suspension all mountain bike with plus size tires, hydraulic disc brakes, high capacity battery, and a lightweight Brose S Mag mid-drive. 27” x 2.8” plus sized tires provide increased traction, great float, and improved comfort while…...

BULLS E-STREAM EVO AM 3 27.5+ Review

  • MSRP: $5,799
  • MODEL YEAR: 2019

A full suspension all mountain bike with plus size tires, hydraulic disc brakes, high capacity battery, and a lightweight Brose S Mag mid-drive. 27” x 2.8” plus sized tires provide increased traction, great float, and improved comfort while…...


  • MSRP: $4,899
  • MODEL YEAR: 2019

A fat tire electric trail bike with a RockShock Bluto suspension fork, remote lockout, 11-speed Shimano Deore XT drivetrain with Shadow Plus clutch, robust skid plate and alloy drivetrain guides. High-torque Bosch Performance Line CX motor with eMTB drive mode, sand and snow capable if…...

BULLS E-CORE EVO EN Di2 27.5+ Review

  • MSRP: $8,499
  • MODEL YEAR: 2019

A full suspension electric all-mountain or enduro mountain bike with a dual battery setup, 180mm travel, large 27.5" plus sized tires, and Boost hub spacing for strength, made in three frame sizes. RockShox in the front with great stanchions, Fox Float X2 in the rear, Shimano STePs…...


  • MSRP: $4,799
  • MODEL YEAR: 2019

One of the most popular models in the Bulls ebike lineup, it comes in four frame sizes and three styles (high-step diamond, mid-step, and step-thru wave), motor and battery weight are low and center, battery is very high capacity at 37.5v 20ah. Extremely stealthy, the drive system and battery are almost completely hidden on this frame and…...


  • MSRP: $5,099
  • MODEL YEAR: 2019

A comfortable full suspension urban electric bike with adjustable upright body position, wider Boost hub spacing and sturdy thru-axles front and rear, high volume tires offer comfort and stability, they don't have reflective sidewalls but they do offer puncture protection. Totally blacked out aesthetic, everything matches and looks very cool, wires and cables are internally…...


  • MSRP: $4,999
  • MODEL YEAR: 2019

A high speed gravel grinder electric bike, complete with flared drop bars, puncture resistant studded tires, and a paint-matched spring suspension fork offering preload adjust and lockout. Excellent weight distribution, beautiful Bosch PowerTube battery integration that frees up the main triangle for…...


  • MSRP: $4,899
  • MODEL YEAR: 2019

A women's specific full suspension electric mountain bike with high quality hardware from Shimano, Magura, Fox, Schwalbe and Bosch, available in two frame sizes with sloped top tube for easy mounting and stand over. Highly adjustable air shocks are lightweight, allow you to sag the frame to match your…...


  • MSRP: $5,499
  • MODEL YEAR: 2019

One of the only full suspension mountain bikes from a premium brand that offers Class 3 high speed performance (28mph, 45km/h), long travel 150mm air suspension supports all mountain riding. Excellent weight distribution and drive system integration, the motor and battery are virtually hidden in…...


  • MSRP: $3,999
  • MODEL YEAR: 2019

Sporty urban electric bike available in metallic grey or glossy white, premium fenders and front rack add utility, mounting points for a rear rack and bottle cage, quiet Brose Drive T mid-motor. Beautiful stitched ergonomic grips and leather saddle from Velo, unique brown tires with whitewall sides…...

BULLS Cross Lite EVO Review

  • MSRP: $4,399
  • MODEL YEAR: 2019

One of the most popular BULLS electric bikes, available in three frame styles and four frame sizes, fully-integrated Bosch PowerTube battery looks great and improves balance. Powerful Bosch Performance Line CX motor offers high torque for heavy loads and capable climbing,…...


  • MSRP: $3,199
  • MODEL YEAR: 2018, 2019

A feature-complete city ebike running the new Bosch Active Plus motor, it's lighter, more efficient, and quieter than previous Active Line iterations, and the compact design is very hidden. Integrated lights and reflective tires keep you safe, the unisex color scheme is professional and…...


  • MSRP: $3,999
  • MODEL YEAR: 2018, 2019

A sporty speed pedelec with beautiful motor, battery, and able integration, the grey and black color scheme help the drive systems blend in, three frame styles to choose from (wave, step-thru, diamond). Bosch Performance Line Speed motor offers ~28 mph support, shift detection, and 120 RPM pedal…...


  • MSRP: $5,399
  • MODEL YEAR: 2018

A high-end, full suspension, electric mountain bike, with the high-torque Brose S mid-motor, and a high-capacity 37 volt 17.5 amp hour Lithium-ion battery, excellent weight distribution with hidden drive systems. Rugged all-mountain performance with 150 mm RockShox air suspension front and rear, 15 mm and…...


  • MSRP: $4,399
  • MODEL YEAR: 2018, 2019

One of the stealthiest 28 mph urban electric bikes I have seen, the Bosch Powertube battery pack is completely hidden inside the downtube and the compact black motor casing blends perfectly with the matte black paint job. The mid-motor is angled up to blend into downtube visually, increase ground clearance, and shorten…...


  • MSRP: $7,399
  • MODEL YEAR: 2018, 2019

A top-end all mountain electric bike with 150 mm suspension from Fox, Shimano Deore XTR 11-speed drivetrain, Bosch CX high-torque motor, and Magura MT Trail hydraulic disc brakes. Wider Boost hub spacing offers a strong bracing angle for the spokes and room for…...


  • MSRP: $3,899
  • MODEL YEAR: 2018, 2019

A high-speed 28 mph commuter style electric bike that comes in four frame sizes and three styles (high-step, mid-step, and step-thru), it offers excellent weight distribution (motor and battery are positioned low and center). Beautiful aesthetic with hidden wires, an internally mounted battery, and a smaller motor casing, the…...

BULLS E-CORE Di2 FS 27.5+ Review

  • MSRP: $5,999
  • MODEL YEAR: 2018, 2019

A full suspension electric trail or enduro mountain bike with 150 mm travel, large 2.8" plus sized tires, and Boost hub spacing for strength, made in three frame sizes. All-black frame, fork, and anodized RockShox stanchions makes for a mean look, Shimano STePs E8000…...


  • MSRP: $3,799
  • MODEL YEAR: 2018

One of the most popular models in the Bulls ebike lineup, it comes in four frame sizes and three styles (high-step diamond, mid-step, and step-thru wave), motor and battery weight are low and center. Extremely stealthy, the drive system and battery are almost completely hidden on this frame and…...


  • MSRP: $5,499
  • MODEL YEAR: 2018, 2019

Top of the line, full suspension, fat tire electric trail bike with RockShock Bluto and Monarch air, remote lockout for the fork, 11-speed Shimano Deore XT drivetrain with Shadow Plus clutch, robust skid plate and alloy drivetrain guides. High-torque Bosch Performance Line CX motor with eMTB drive mode, sand and snow capable if…...


  • MSRP: $5,499
  • MODEL YEAR: 2018, 2019

An all-mountain style electric bike with longer travel 150 mm air suspension from RockShox, an internalized downtube battery from Bosch, and three frame size options. Fatter 2.8" plus sized tires provide increased traction, reduced deflection, and improved comfort while remaining…...


  • MSRP: $3,299
  • MODEL YEAR: 2018, 2019

A feature-complete cruiser style electric bicycle with paint-matched fork, fenders, rear rack, chain cover, and motor casing, available in three frame sizes with adjustable stem for good fit. Large sprung saddle, puffy stitched grips, swept back handlebars, and the deep step-thru frame make…...


  • MSRP: $4,299
  • MODEL YEAR: 2018, 2019

A full suspension, cross country style, electric mountain bike made just for the ladies with shorter reach, available in two smaller size options, features a turquoise fuchsia colorway. Sturdy Suntour XCR 34 air suspension fork with remote lockout for easy transitions from rough…...


  • MSRP: $2,899
  • MODEL YEAR: 2018, 2019

A tough, sporty looking, high-quality, kids electric bike that can reach ~15.5 mph with four levels of pedal assist, smaller wheels keep the frame low and approachable. Premium accessories including tires from Schwalbe, a Shimano Altus 8-speed drivetrain, and Tektro hydraulic disc…...


  • MSRP: $2,799
  • MODEL YEAR: 2017, 2018, 2019

Well priced considering the quality Bosch-made electric drive system, four frame size choices, and three frame styles (high, mid, and low-step). Integrated LED lights and premium Continental tires with reflective sidewall stripes help to keep you…...

BULLS E-STREAM EVO FS 2 27.5 Plus Review

  • MSRP: $4,099
  • MODEL YEAR: 2017, 2018

One of the cleanest looking full suspension cross country electric bikes I've reviewed, the battery and motor are built into the frame and match the matte black paint perfectly. Extra large battery capacity for longer rides, EnergyBus magnetic charging standard works on or off…...

BULLS SIX50 E 1.5 Review

  • MSRP: $3,099
  • MODEL YEAR: 2017, 2018, 2019

A hardtail trail ready e-bike with comfortable plus sized tires and a spring suspension fork (with lockout), sturdy tapered head tube, rigid thru-axles, and Boost. Capable as a commuting platform if you prefer a mountain bike vs. hybrid or city…...


  • MSRP: $4,099
  • MODEL YEAR: 2017, 2018

An active, sporty looking, commuter style electric bike with low standover height, available in three frame sizes to improve fit and comfort. High-end drivetrain and motor systems, you get eleven gears with a tough mountain bike level…...

BULLS SIX50+ E FS 3 Review

  • MSRP: $4,699
  • MODEL YEAR: 2017, 2018

An all-mountain electric bike with plus sized tires for improved stability, traction and comfort, 150 mm air suspension with compression and rebound adjust. Battery and motor mount design are tighter than older Bosch systems, weight is kept low…...


  • MSRP: $5,199
  • MODEL YEAR: 2017, 2018

A high quality full suspension e-mountain bike that's also a speed pedelec (capable of 28 mph top speeds), solid hydraulic disc brakes, wide thru-axles with Boost Technology. Adjustable 150 mm RockShox suspension front and rear, four-bar rear swing arm to reduce brake…...

BULLS E-STREAM EVO 3 Carbon 27.5 Plus Review

  • MSRP: $4,599
  • MODEL YEAR: 2017

A Carbon fiber electric cross country mountain bike with premium components and ultra-integrated motor and battery system, excellent weight distribution. The Brose motor is quiet and responsive offering up to 90 Nm of torque output,…...


  • MSRP: $5,799
  • MODEL YEAR: 2017, 2018

One of the first Gravel Grinder style electric bikes to make it to America! Made with premium components, high performance lights and a purpose built frame in three sizes. Capable of high speed 28 mph performance, the Bosch centerdrive motor measures bike speed, pedal…...


  • MSRP: $3,899
  • MODEL YEAR: 2017, 2018, 2019

A fully equipped speed commuter capable of 28 mph operation, running on the proven Bosch Performance mid-drive motor and updated 500 watt hour Samsung battery. Extra large 203 mm hydraulic disc brakes offer smooth solid stops without requiring exorbitant hand…...


  • MSRP: $3,999
  • MODEL YEAR: 2017

A versatile urban electric bike well suited to commuting, touring and trekking because of its efficient mid-drive motor and larger than average battery capacity, durable internal gearing and belt drive. Available in five frame sizes and three frame styles including wave, mid-step and high-step diamond…...

BULLS E-STREAM EVO FS 3 27.5 Plus Review

  • MSRP: $4,699
  • MODEL YEAR: 2017, 2018

A stealthy full suspension all-mountain electric bike with longer travel 150 mm suspension, fully adjustable air fork by RockShox, color matched to frame. Larger 37 volt 17.5 amp hour battery pack to assist with steeper climbs and longer…...


  • MSRP: $5,299
  • MODEL YEAR: 2017

Full suspension fat bike with a high quality mid-drive motor from Bosch and their updated 500 watt hour battery pack for extended range. Cool fluorescent paint job that extends all the way through the fork, rear shock housing,…...


  • MSRP: $4,399
  • MODEL YEAR: 2017, 2018, 2019

Available in four frame sizes, two styles (high-step and mid-step) with an adjustable stem, active-comfort saddle and ergonomic grips, this bike can fit well and feel good at speed and over long distances. Capable of 28 mph top speeds, this is a Class 3 electric bike with an…...


  • MSRP: $4,699
  • MODEL YEAR: 2016

An all-mountain electric bike with beautifully integrated battery, motor and display... it blends in more than most other e-mountain bikes I've tested and runs quiet. Sturdy 15 mm thru axle in the front and 12 mm axle in the rear…...


  • MSRP: $4,599
  • MODEL YEAR: 2016

A loaded full suspension mountain bike with premium electric drivetrain from Bosch offering 75 Nm of climbing torque with the CX motor and a 400 watt hour Samsung battery. RockShox air suspension with 120 mm travel front and rear for solid trail or all…...


  • MSRP: $4,299
  • MODEL YEAR: 2016, 2017

Premium hardtail electric fat bike with all the fixins, highlights include rear rack bosses, tubeless-ready tires and punched out rims, RockShox air fork with remote lockout and high torque Bosch CX motor. Quality 180 mm hydraulic disc brakes from Shimano for excellent stopping power and modulation, impressive…...


  • MSRP: $3,999
  • MODEL YEAR: 2016

A sporty looking, fairly comfortable speed pedelec capable of ~28 mph top speeds, it's running on an optimized geared hub motor design with heat pipe technology for maximum performance. Unique mid-mount battery box fills the main frame triangle keeping weight low and centered while…...


  • MSRP: $3,699
  • MODEL YEAR: 2016

A beautifully designed urban electric bike painted white for visibility and modern appeal, white walled tires, reflective sidewall stripes, LED lights. Extra sturdy and durable thanks to a 15 mm thru-axle on the front wheel (with…...


  • MSRP: $4,599
  • MODEL YEAR: 2016

A full suspension, Bosch powered, cross country style electric bike with efficient 29" wheels, it's available in three sizes for good fit and would feel taller and larger for riders with long legs but still fits some shorter riders given the angled top tube. Quick release for both wheels ads convenience for fixes and transporting the bike, I love…...


  • MSRP: $3,699
  • MODEL YEAR: 2016

Fully loaded urban electric bicycle with great accessories for commuting including an aluminum rear rack, full length fenders with mud flaps and integrated LED lights. Relatively light weight at under 50 lbs, this is due in part to the nicer…...

BULLS E-STREAM EVO FS Enduro 27.5 Review

  • MSRP: $5,399
  • MODEL YEAR: 2016

An enduro style full suspension electric mountain bike with longer 160 mm suspension travel, seat post dropper, 27.5" wheelset and premium hydraulic brakes. Downtube-integrated battery pack is out of sight and keeps weight low and centered across the…...

Comments (4) YouTube Comments

James B
5 months ago

Fine review. I enjoyed it very much. You should try to take on some hills–if your knee will allow it–I mean show some real MTB riding. I realize that would require both hands on the bar but maybe you can mount the camera on your helmet or somewhere on your front.
But I really want to inquire further about the water bottle. My R&M Homage is scheduled for build at the end of the month. As you know, it comes with no water bottle bosses so I will have to rig something. This MonkeyLink bottle looks like it could be a good solution. I would have to add two straps for the bosses but I like not having a cage for the bottle. It would be even better if the base mount came with its own tube straps so bosses wouldn’t be necessary. Do you know if SKS offers this as an option? I would like to get your opinion about this bottle and the best way to mount it. Is the magnet strong enough to hold a full bottle or is there any chance of the bottle popping out while riding? Thanks for any and all information. Cheers.

4 months ago

Hi James, the magnets in the mount seem very strong and there are two circular rods that protrude and grab the base of the bottle as it twists in. I do think that it would be fine with a full bottle and I agree that it takes up less space and is easier to remove/reinsert than a traditional friction mounted bottle cage. I haven’t used MonkeyLink a whole lot, but I haven’t heard a lot of complaints from people besides the higher $45 price point for the bottle.

4 months ago

This is your first review with the Kiox? Aside from color, what advantages does it offer over Intuvia? Or would you prefer the Intuvia? It seems like the 10bar battery power display is the big leap. Otherwise, without GPS like the NYON, it’s a bit underwhelming.

4 months ago

Hi Shaggy, the Kiox is removable using magnets vs. a plastic clip. It’s designed to fall off without breaking the mount and the screen is made from Gorilla glass, so it’s very scratch resistant. Also, it connects via Bluetooth and may have some apps in the future. I like that it has the Micro-USB charging port built in and how it’s positioned low and more compact, and has color, compared to Intuvia. I think it’s a hybrid of durability, stealth, and externalizing apps vs. the Nyon, which isn’t available in North America. Their other big display system is going to be COBI, which uses your smartphone for everything :)


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