Bergamont E-Trailster 9.0 - eMTB Review

Bergamont have supplied us with some killer test bikes in the past, with their Trailster 140mm travel trail bike still being one of my favorite trail bikes for its solid feel and good manners. The E-Trailster hopes to build on that same and concept with the addition of a Bosch Performance CX motor, a 500wh battery, and a chain-growth neutralizing idler wheel to minimize torque feedback from the simple, single-pivot rear suspension.

The E-Trailster 9.0 we tested is their top of the range model, retailing at a modest (compared to other eMTB's) €5199 and is spec'ed with a RockShox Pike fork and a Monarch shock; a SRAM EX1 drivetrain; Magura MT4 brakes; a Sun Ringlé wheelset; a predominantly Answer cockpit; and it showcases Manitou's new Jack dropper seatpost.




Details and Build

The E-Trailster has a 6066 alloy, welded aluminum frame, that includes a tapered head tube and internal cable routing. The axle spacing is not Boost width: 142mm rear and 100mm front - which arguably, is outdated for a 2017 eMTB. I'm not a boost fanboy, but if you are spending a chunk of money on a bike in 2017, it seems like a bad idea to drop behind trend when it's clear to see that the industry has made the decision to support Boost. On that same subject, the narrow, 24mm rims are also outdated, as were the narrow and mid-weight Maxxis Forecaster 2.35" width, Exo casing tires These were switched after ride number one to something heavier duty from the depths of my shed - a Super Gravity Magic Mary from Schwalbe and a Maxxis High Roller in the DH casing.


The suspension is controlled by a 150mm travel Pike RCT3 fork, and a Monarch RT3 HV shock handles its 140mm travel rear suspension. SRAM's EX1 8-speed eMTB specific drivetrain and cranks connect the Bosch motor to the rear hub and to stop the bike, Bergamont chose Magura MT4 brakes, which appear under-powered. Their four pot brothers would seem the more sensible choice. Always choose extra power when weight isn't really an e-issue.



Suspension Design

The aluminum frame uses a high swingarm pivot-point, located above and behind the Bosch motor. The seat stay pivot is located very close to the rear wheel's axle and there is a short rocker link mounted to the seat tube to drive the shock. An idler wheel and retention guide are located on the main pivot axis. The chain runs over the idler to eliminate chain feedback - similar to what we see on Commencal's latest downhill bike and some classic downhill bikes of the past.






Geometry/Sizing

I opted for the XL sized frame, which has a 463mm reach, 66.5º head angle, a 74º seat angle and a 475mm chainstay. The bottom bracket sits 18mm below the wheel axles. It's interesting to note that the E-Trailster only increases by 10mm per size, from the medium up to the extra large - not a significant difference in frame size compared to the wide range of body types that will be riding them.




Motor

Bergamont uses the Performance CX Line motor from Bosch, along with the external 500wh PowerPack. The Bosch motor is currently the most popular on the market and the 500wh battery is one of the largest and most commonly used. Our bike came with the Bosch Purion display, with the software updated to 'eMTB' mode, which is now a free upgrade for on all Bosch powered bikes. This mode gives the rider the access to the whole range of power available, rather than switching between modes – pedal harder and you get more power, spin along gently and you will get the least assistance.

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Climbing and Trail

The E-Trailster is one of the easiest eMTB's for climbing I've reviewed so far. The massive, 475mm-long chainstays help to keep the front end down, even when giving it voll gas on the climbs. The saddle position is the furthest forward in relation to the bottom bracket (180mm behind the BB on a horizontal plane) compared to any other eMTB I have tested, this gave a central position to attack the climbs.

The lack of pedal feedback through the chain and great support from the suspension lets it float over rough terrain easily, and it doesn't wallow with the shock's compression lever left open. I am finding that eMTB's require less anti-squat than a normal bike. The majority of the power now comes from the smooth, circular drive of the motor, instead of the jabby motion of a human's legs, which are not designed specifically for pedaling.



Bosch's latest eMTB specific power mode is fantastic. It makes tackling technical sections and tight corners simpler, as it's easier to feed the power gently through the cranks, and then gives you a boost when you drop the hammer in order to pop up and over obstacles. Using the normal Trail or Turbo modes often left you overcooking it around tight corners, or not having the power needed for short boosts up and over short climbs.




Descending

This is where the E-Trailster gets interesting. The mere 140mm travel, combined with the added weight of motor and battery, might be the best rear suspension system I have ever used on any bike, massively outperforming its actual travel. Plowing straight through rough sections, I thought the forks were broken. I felt impacts through the fork, but rarely did those impacts affect the rear suspension when the back wheel struck an obstacle.

As I have found in the past with suspension that use high pivots with no pedal kickback, the action through braking bumps and big hits is unbeatable, especially for flat pedal riders, who will find their feet always planted however rough it gets. Hitting huge holes or landing drops, the anticipated kick into the ankles never came and bottom out was almost unnoticeable. Such suspensions are normally compromised by pedal bobbing – highlighted by poor pedaling technique, but this issue doesn't come to light on the electric-assisted machine. The downside of this appears to be a difficulty in creating grip on smooth and flat corners. When you want to drive the rear wheel into the ground to generate grip, it seems to move off line and start to slide.

The Trailster outperforms what we would expect from its listed numbers, probably due to the heavy weight and improved sprung to unsprung mass ratio when compared to a non-assisted bike. The front portion of the bike could be slacker for even better descending, but that might just get me into high-speed trouble. The whopping 475mm chainstay length comes in to play here, giving big stability everywhere. Manuals were a little tough to start with, but a learned change of timing and heft meant that I could raise the front over any obstacle. Using a half crank timed with the motor boost to lift the wheel is another technique to be learned on an eMTB.

The E-Trailster felt vague compared to some other eMTB's I have on test. This could be due to a number of reasons: the small diameter tubes in the front triangle and the extra long rear end also seemed to create some flex, and I found lots of tire roll from the narrow rims. It also feels sluggish for eMTB, but however vague the feel might have been, the E-Trailster is a good platform in terms of pure downhill speed, its suspension, and its ability to take lines that others can't.




Technical Report








Pinkbike's Take:

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Posted In:
eMTB Bergamont