Mountain Bike Action Bike Review: Bulls Adventure EVO Am eTrail Bike
BULLS ADVENTURE EVO AM
With the current trend of the super-light e-bikes from many major manufacturers, it’s interesting to see another trend coming, which is the complete opposite. Where the SL bikes emphasize smaller batteries for those who want a little assist but a lighter, more nimble bike, the multi-battery bikes offer greater range at the cost of a few extra pounds.
The Bulls Adventure Evo AM is at the head of this trend. It’s designed for riders who want to explore more, with twice the range of a normal, Bosch-powered e-mountain bike.
The Adventure EVO bike has an aluminum frame with a Bosch 625-Wh PowerTube integrated into the down-tube. What’s unique is the 500-Wh PowerPack battery slung under the top tube, offering more than twice the range as a traditional, single-battery bike. Fox Float suspension gives this bike 150mm of travel. Cable routing is internal through the frame.
The Fox Rhythm 36 fork is e-bike-specific and has adjustable high- and low-speed compression with lockout. The bike rolls on 27.5-inch aluminum, double-walled Bulls Eccentric 35 rims mounted with a mixed combo of Schwalbe tires.
The Magura MT5 quad-piston brakes are mated with 203mm rotors and are easy to modulate, whether you need to scrub a little speed or come to a quick halt. The speed sensor is built into the frame, and the magnet is on the rear brake rotor.
Interestingly, Bulls designed the bike to feature three different suspension-travel lengths for the four different frame sizes: 100mm of travel for the 41cm frame, 125mm for the 44cm, and 150mm for the 48cm and 54cm.
This bike, like many from Bulls, comes with MonkeyLink mounts for lights. There’s one at the bottom of the stem and one at the seatpost clamp. They’re pre-wired, so you simply insert a (optional) MonkeyLink light into the receiver, and it’s then fully powered by the battery system.
The bike is powered by a Bosch fourth-generation Performance Line CX motor, which has been updated to bring it up from 75 N/m of torque to 85 N/m, along with some upgrades in how it responds to short pedal strokes when climbing technical terrain while trying to avoid pedal strikes. Unlike previous generations of the CX, this one has no reduction gearing internally and uses a full-size 34t chainring.
There are four power modes: Eco, Tour, e-MTB and Turbo. Eco offers the least pedal assist, whereas Turbo offers 340 percent of what the rider torque input is. The e-MTB mode replaces Bosch’s usual Sport mode, and it varies assist level based on rider-torque input. The harder you pedal, the more assistance it gives you, in a fully glissando way, from Tour to Turbo. This can ultimately save you some power when you don’t really need it, which can extend your range.
The battery system is very smart. There’s a big 625-Wh battery in the downtube and a removable 500-Wh battery under the top tube, giving you a total of 1125 Wh. The way it works is that the power is pulled from the 625-Wh battery first until it reaches the same capacity as the 500-Wh battery, then the system alternately pulls about 5 percent from each. This allows less stress on the batteries, which offers longer range and better battery life. When charging the batteries on the bike, the system handles how it charges the batteries, so you can set it and forget it.
Part of the cost of this bike is packaged in with two batteries. A single 500-Wh Bosch PowerPack sells for upwards of $900. This bike not only has two batteries, but a smart system designed to handle them in tandem.
The display is a Bosch Kiox, which offers a full-color display and all the information you want about battery level, power mode, torque input and more, and it offers integration with some heart-rate monitors, as well as turn-by-turn directions on a map. There’s not a lot of detail like street names on the diminutive Kiox screen, but if it did have that detail, it would be harder to read.
WHO IT’S MADE FOR
The ideal rider for the bike is right in the name—someone who craves adventure. With 150mm of travel and such high battery capacity, this is a great bike for going on long rides, exploring, possibly even camping trips. It can let you go twice as far, using the same power-assist mode, without having to carry an extra battery.
With the extra battery attached and wired in, the weight is kept lower and riding is easier. If you’ve ever carried a 5–6-pound battery in a backpack, it’s not only a bit unwieldy, but if you fall, that extra weight is going to drive you that much harder into the ground. Trust us on this, we found out the hard way!
One of our test riders loves to go on extended group rides where they carry an extra battery. He was the perfect choice for this test. The group is made up almost entirely of Bosch-powered bikes, so they can not only carry spare batteries, but share them if needed. They all ride together, and usually always in Turbo mode to keep up with each other on rides that include thousands of feet of climbing.
For all-around use, the bike felt very balanced, comfortable and inspired confidence in technical terrain. Everyone appreciated the extra range of two batteries, and that lugging one in a backpack was no longer necessary. To place the weight even lower, some would prefer to have the 5-pound, 4-ounce battery mounted on the top of the downtube instead.
The 2.8-inch tires proved grippy and confidence-inspiring. The bike does feel planted, though we’re sure some of that comes from the extra weight on the frame.
Everyone thought the 150mm of travel from the Fox Float suspension was divine. With sag set at 30 percent, there was nothing we threw at it that it didn’t soak up. Small-bump compliance was excellent and kept us in contact with the ground, and ready to keep going wherever we pointed the bars.
Oddly, the FSA cranks are drilled to a 165mm size, but they further extend almost 3/4 of an inch below the pedal spindle. Companies do this to minimize production costs, but here, it is a liability when it comes to increased pedal strikes. Luckily, there’s some amelioration of this, thanks to the new Bosch software that allows a partial pedal when climbing technical stuff, as it senses this and offers motor power for about a half second past when you stop moving the pedals.
The build quality of this bike, along with the decimation of any range anxiety, makes the Bulls Adventure bike a serious contender for anyone who likes to go on long rides. The ability to swap out the external battery easily means you can carry more spare batteries to go even farther, but even the two together make it one of the longest-range bikes we’ve ridden.
BULLS ADVENTURE EVO AM
Motor: Bosch Gen 4 Performance Line CX
Battery: 1 625-Wh PowerTube + 1 500-Wh PowerPack
Charge time: 5–6 hours
Top speed: 20 mph (Class 1)
Range: 25-50 miles
Drive: Shimano XT, 1×12
Brakes: Magura MT5, 4-piston hydraulic disc, 203mm
Controls: Bosch Kiox
Fork: Fox Float Rhythm 36 e-bike, 29” 150mm travel
Rear shock: Fox Float DPS, 150mm travel
Frame: 6061 aluminum
Wheels: Bulls Eccentric 35, 27.5”
Tires: Schwalbe Magic Mary Snakeskin (F) 27.5x, Schwalbe Hans Dampf EVO Snakeskin 27.5×2.8” (R)
Weight: 67 lb.
Color choice: Silver
Sizes: 41, 44, 48, 54cm
Mountain Bike Action is a monthly magazine devoted to all things mountain biking (yes, that’s 12 times a year because we never take a month off of mountain biking). It has been around since 1986 and we’re still having fun.