Cairn Cycles has just launched their 2021 E-Adventure V2 electric gravel bike with frame and specification updates. Sticking with the Fazua Evation motor, the lightweight e-gravel bike will be available in two different build options, both at a pocket-friendly prices. 

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This new Cairn E-Adventure V2 builds on the first version of the bike and it’s still a Fazua Evation driven e-bike built for big days adventuring off-road. Cairn says they realised the improvements they needed to make for V2 and have gone about sorting them out for the 2021 bike. New things for 2021 include different cable routing, repositioning of the Fazua control unit plus removing the seat stay brace, a lowered standover, and updating the spec and colours too. 

 

 
The 2021 Cairn E-Adventure is a lightweight electric gravel bike built to run with or without the motor and battery. It's built for multi-day epic trips, weekend exploring or commuting with two builds available each with a specific purpose. Keeping it simple with two builds is a great idea, there’s a more all-road 700c version that gets Hunt Gravel X Wide Rims with E-gravel hubs, Vittoria Terreno Dry 38c tyres, Ritchey 4-Axis stem, Ritchey Butano Comp bars with Fabric Knurl bar tape, a Fabric saddle and a fixed carbon seat posts.

 

Then there’s the 650B version that gets 650B Hunt Sport Disc rims, a chunkier Vittoria Mezzcal 2.25” front tyre and a 2.1” rear tyre. The 650B bike gets Cairn 20 degree flared bars, a Carin Adventure stem in various shorter sizes,  Cairn bar tape, own brand saddle and an 80mm Trans-X dropper post too.

 

 

The theme is clear – 700c bike for mile-munching, 650b bike for razzing singletrack. Both come in at £2989 for the full build and both have the same spec otherwise, consisting of:

• Alloy frame with carbon fork and thru axles front and rear
• Praxxis Fazua Crankset
• Shimano GRX RX600 groupset

 

 

New V2 frame details

First up, there’s a lower standover opening the bike up to smaller riders, it also means that there is a shorter seat tube which gives more room for dropper posts.  It also means that for those folk running a fixed seat post, they'll be treated to more compliance as more of that post is exposed above the seat tube of the bike. 

 

Cairn has also revised cable routing, the cables now enter the bike at either side of the top of the down tube rather than through the head tube. This cleans up the looks of the bike as well as giving more room for the cables rather than squeezing them together as the head tube.

 

Most interestingly, the rear seat stay bridge has been removed on the new bike. Now replaced by a small removable bridge that is just connected to the bike on the drive side seat stay. This small bridge can be adjusted in height and used to affix mudguards. Cairn fixing this just one side helps increase compliance too, plus makes it easy for a rider to remove it for a cleaner look if they aren’t planning on running mudguards.

The Fazua remote has also been moved from the top of the downtube (directly under the top tube) to the top of the top tube improving the visibility of battery level indicators and given the rider clearer access to change modes. The brand previously located the remote on the down tube so riders could still use frame-mounted top tube bags but have forgone this and given the remote some real estate on the top tube for quicker and better rider access. 

 

Spec updates

Elsewhere the bike gets the new(ish) Shimano 1 x GRX RX600 groupset which the brand says they wanted to use as it’s the only gravel specific groupset out there and they prefer it to SRAM Apex. Last year the E-Adventure V1 used a Praxxis crankset with SRAM Rival mech and brakes. The bikes also get the new Hunt E-Gravel disc wheels with a 25mm internal width and a steel axel for longevity, 5mm wider than the Hunt Four Season rims used for V1 in 2020. The wheels are built around Hunt’s E-gravel hub where the freehub has a bigger surface of engagement at the pawls to deal with the increase in torque. 

Finally, the bike with its Fazua Evation motor benefits from the recent Black Pepper updates. These updates allow the rider to have much more control over how the motor performs. Cairn has utilised this further creating a new Cairn Specific tune which you can use to set up your new bike and get the most out of it, according to the experts that built the bike. 

 

 

The brand also sells extra batteries and a Cairn Battery Keg so you can carry a spare 1kg batter inside the front triangle of the bike for an even longer range of you want it. That extra battery costs £399 and the Keg costs £32.

 

 

Geometry

The geometry of the bike remains largely unchanged aside from that lower standover and seat tube which is down 40mm to 500mm on a medium sized bike. The head tube stays at either 71 or 72 degrees (size dependant) and the seat tube angle is identical too at 73 degrees. Elsewhere the chains stays are just half a centimetre longer at 430mm and reach and effective top tube figures are identical, for example, 384mm and 558mm respectively on a medium. 

 

The bikes are available now, for pre-order. You’ll need a £299 deposit to secure one, then the full price of the bike is £2989 minus your deposit. You can expect delivery of the bike at Christmas, where on arrival all you’ll need to do is put the front wheel and fit the bars. In the box there will be a small torque wrench with all size bits needed for the assembly. 

Our resident gravel reviewer Matt will soon have a bike for review so check back soon to hear his thoughts. 

• www.cairncycles.com

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