Lapierre Zesty AM 427 E:I – first ride review

Trail all-rounder gets a smart suspension boost

Our rating 
3.5 out of 5 star rating 3.5
GBP £2,950.00 RRP

Our review

Some niggles, but smart suspension gains top performance from an already solid trail bike
Skip to view product specifications

Lapierre’s Zesty was the full gas trail riding benchmark for several years and while other brands have caught up with and sometimes even passed the basic chassis dynamics of the current model, this E:I equipped version is still a great package. E:I is not exclusive to Lapierre – Ghost and Haibike share the technology – but the way it reads and reacts to the trail is on a different level to any other suspension technology.


Frame and equipment: smart shock gets an update

An accelerometer fitted to the leg of the conventional RockShox Revelation fork tells the E:I processor what size of hit the fork is dealing with. A crank turn sensor in the bottom bracket adds information on pedalling speed and then the E:I processor then works out the ideal compression setting of the rear shock from fully open, platform damped or soft locked according to this impact and pedalling information.

Before the back wheel gets to the same patch of trail, a motor mounted on the rear shock adjusts the valving accordingly. It’s always worked incredibly well for such a sophisticated system and the latest version is even better. The big stem top mounted computer has been replaced by a smaller unit on the side of the stem which communicates current compression mode via a red, amber or green LED and lets you choose between automatic or manual mode selection.

Lapierre’s solid basic chassis is further improved by e:i technology:
Russell Burton

Lapierre’s solid basic chassis is further improved by E:I technology

However clever E:I is, it’s still just an automated compression change mechanism on Lapierre’s already sorted, totally conventional OST+ rear suspension. If you’re happy setting and not forgetting conventional suspension, you could trim your outlay by going for the standard 427 AM, or shave 600g by opting for the slightly pricier carbon mainframe Zesty AM 527.

The E:I system undoubtedly flatters climbing and acceleration performance though, and the 14.4kg weight is ballpark with bikes of similar capability. A 1×10 conversion would save weight over the double setup too.

Ride and handling: electronic magic tempts you to push the limits

Hop in the saddle and the E:I seems more sensitive than before too, so you don’t have to run the fork softer than normal. The way it switches instantly from fully active to solid lock for a sudden burst of sprinting is properly magic and it synced with the setting we’d have chosen 95 percent of the time. You can then run lower pressures in the rear shock for better sensitivity and ground connection from the already excellent Monarch unit.

It also tips the bike backwards, slackening the steering angle. Despite initial concerns about survivability it’s been totally reliable on several short-tremors and one long term bike even in freezing weather or after cartwheeling crashes. It sleeps and restarts automatically to save battery life too, with a fully open failsafe mode if the battery does die.

The new, stem mounted e:i shock control unit is neater:
Russell Burton

The new, stem mounted shock control unit is neater

The Zesty’s excellent back end does puts a lot of pressure on the 32mm legged Revelation fork. That reveals obvious twist and flex issues when you’re turning in hard or trying to burst the brake lines on the Shimano XT anchors under maximum deceleration.

We also had occasional deflection related spikes in the stroke when we slapped the front end into blocks or off drops at high speed and we’d certainly be happier with the thicker 35mm legs of a RockShox Pike up front to show the trail who’s boss. We junked the hard ‘Performance’ compound Schwalbe Nobby Nics for something with more consistent wet grip after the first ride too.

The relatively narrow rims on the Race Face Turbine wheels limit stable tyre girth to 2.3-2.35in. They are easy to turn tubeless, which is worth doing. You also need to watch the dropper cable where it comes out of the seat tube as the outward loop can easily rub the chainring or even get caught by the chain if you alter the post position in the frame without taking up the slack via the external cable clamps.

The impressively updated e:i system had us hammering the zesty in no time:
Russell Burton

The impressively updated E:I system had us hammering the Zesty in no time

The fact we were happy pushing the Zesty hard enough to outrun the tyres and fork is sign of a bike that definitely encourages a positive attitude. We felt a lot less perched and precarious than on the Zesty AM 527 we tested a couple of months ago, suggesting a lot of that composure and connection comes from the E:I system – or at least the way it lets you set up the Monarch shock.


We’d rather the 55mm stem seen on small and medium bikes was used right across the range, as the 625mm top tube on the large is certainly long enough to cope. The 740mm bar width is appropriate for a fork you can already turn harder than it really wants to.

Product Specifications


Name Zesty AM 427 E:I (15)
Brand Lapierre

Bottom Bracket Shimano
Rear Derailleur Shimano XT Shadow Plus
Stem Lapierre CNC by FUNN
Shifters Shimano SLX
Seatpost KS Lev Integra
Saddle SDG Duster LP
Rear Tyre Schwalbe Nobby
Rear Shock RockShox Monarch E:I RT3 Fast
Headset Type FSA Orbit
Brakes Shimano Hydraulic XT
Handlebar Lapierre Nico Vouilloz Signature by FUNN
Front Tyre Schwalbe Nobby
Front Derailleur SRAM X7 S3 36T
Frame Material Zesty AM Alloy
Fork RochShox Revelation RL Fast Solo
Cranks Race Face
Wheelset Race Face