Lapierre's Overvolt AMi trail e-MTB range has now added a carbon fibre framed option to the lineup, meaning there's now less mass to haul about on a bike that already boasted sweet handling and well-sorted suspension. A thorough thrashing around the Portes du Soleil proved it more than capable on almost any terrain.

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The Overvolt Carbon AMi sports 150mm of travel at either end and the option to run either 29" or 27.5" Plus wheels, with some neat adjustable chips in order to preserve the geometry when you make the switch, though it comes as standard with 27.5" wheels and plump 2.8" rubber. 

All the bikes in the range use a Bosch Performance CX motor with the 500Wh battery integrated into the down tube. The move to a carbon main frame has managed to drop a fairly substantial 800g from a medium compared to the aluminium version. That's not just because carbon is lighter than metal - it's because moving to composite allows Lapierre to design the bike - and the motor mounts in particular - in a totally different and much more efficient way.

The back end is still aluminium, something Lapierre does on all their e-bikes for durability reasons - the thinking being that a chainstay is more likely to get bashed and scraped by rocks than most other areas of the bike.

Of course, you might argue that with all the additional heft of an e-bike, dropping a bit of frame weight isn't going to really affect range substantially though, in theory, it should be less tiring to move about when you're riding.

The carbon Overvolt also features slightly tweaked geometry, namely a head angle that's 1º slacker than the aluminium bike at 66º. You also get some neat touches such as the 'Anti Chain Suck' guide mounted to the drive motor and a new rapid access bolt that allows you to quickly and easily remove the battery.

As with the aluminium framed bike, there's Boost hub spacing at either end and the shock gets an eyelet with cartridge bearings in it to reduce friction.

How does it ride?

I took the middle-of-the-range 900 model out for a solid couple of day's riding around the Morzine and the general Portes du Soleil region. The kit list isn't to be sniffed at, with a RockShox Revelation RC with Charger damper, a Deluxe RT shock and a 12spd GX Eagle shifter and mech paired with an 11-50T NX cassette, which is said to be tougher and better suited to the rigours of e-bike use.

The shifter is also modified to only allow one up or downshift at a time, easing the amount of stress you can place on the drivetrain under shifting. It takes a bit of getting used to - trying to dump a load of gears for a sudden climb requires a bit more forethought, but it does massively reduce the number of times your mechanical sympathy is tried by a drivetrain trying to crunch out 500W of motor plus rider stamping on the pedals.

As ever, the Bosch unit is smooth, powerful and refined, with the new E-MTB mode providing assistance that varies in line with how hard you're stamping on the pedals. It's much less obviously 'assisted' feeling than the other modes - turbo especially - and it comes close to emulating Shimano STEPS super-refined and almost natural feel. 

Well, I say natural, but when the bike is merrily hauling you up an incline that you wouldn't even want to push up, that's not the most natural of sensations, though deeply satisfying. It is, as with most electric mountain bikes, deeply addictive however and almost makes climbs more fun than descents. Almost.

Lapierre provides much of the finishing kit, with an own brand 760mm bar paired to a 45mm stem on the large frame I rode - the smaller sizes getting a 35mm item. I'd have preferred a touch more width to the bar for wrestling the not insubstantial bulk of the bike around - I think you'd need to ride this and the aluminium bike back to back to really notice the difference in all-up weight between the two - but that's very much a personal preference.

The dropper post with underbar cable remote is also branded up as a Lapierre unit and it performed impressively well, with a nice feel to the lever and smooth action. It's a bit of a contrast the Bosch's Purion controller, which does display a fair amount of information once you've figured out how to cycle through the screen display, but switching modes isn't particularly refined with big clunky buttons that require you to take a hand off the grip to use. New Bosch systems do have something much better for e-MTBs coming soon, so hopefully that might be a running change to the spec.

Lapierre has fitted SRAM Guide E brakes to all of the Overvolt range and these did a sterling job of hauling up the bulk of the bike, even on the steepest of descents. That's just as well because absolute faith in your brakes gets pretty important when you're hammering down mountains on an e-bike and the Guides coped with nothing more than slightly fragrant brake pads after the longest of descents.

When it comes to the handling, Lapierre hasn't gone particularly new-school with the geometry and the large frame has a not-huge reach of 444mm. I do think that a long reach figure isn't quite as crucial on an e-MTB versus a standard one, namely because the sheer weight of the bike does an awful lot to aid stability. Even on steep and tight trails, the bike never felt precarious, though the lashings of grip on offer from super fat 2.8" Maxxis Minion High Roller II rubber definitely aided things and also helped mute any chatter that got past the fork and shock.

On that count, Lapierre has done a cracking job with the suspension, managing to balance plenty of initial grip with mid-and-ending stroke support that doesn't feel like it ramps up too harshly or firing back too brutally from deep in the travel. It's also nicely communicative on flatter corners, not muting what's going on so entirely that you're unaware when the prodigious grip is about to let go.

In fact, I only have a couple of minor gripes with the Overvolt, namely that the own-brand saddle is definitely one of the most uncomfortably shaped things I've suffered on for quite some time - obviously compounded by the extra amount of buttock thrashing clattering up steep climbs for extended durations on an e-MTB entails. Your bum might get on with it fine, mine most assuredly did not.

On a vaguely related note - and exacerbated by the fact we were doing a lot of very steep climbing - was the relatively slack 73º seat angle that I felt shifted a bit too much weight rearwards on the bike to keep everything nicely weighted at the front when climbing. It's a bit odd as Lapierre's unpowered bikes are fairly progressive in this regard and looping out is one of the few things that gets in the way of an e-bike when going uphill, especially as Lapierre has cannily fitting 165mm long cranks that give enough ground clearance to keep you spinning uphill even on the roughest of terrain.

If you don't mind the odd looks, you can bang the saddle as far forwards as possible to get around this somewhat, but I do think this is one slight weakness in an otherwise extremely impressive package - well that and the fact that you don't seem to be able to buy one in the UK at the moment. C'est la vie...

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