The Arc8 Eero is a fabulous pink go-fast aero gravel rocket with fender mounts

Arc8 releases refreshingly simple and adaptable gravel bike that could replace your road bike

Jack Luke / Immediate Media

Published: November 10, 2020 at 5:00 pm

The Arc8 Eero is an all-new performance-focused gravel bike from the Swiss brand that could be a viable alternative to your road bike.

Featuring aero tube shapes, huge tyre clearances and mudguard mounts, the Eero packs a great deal of cross-discipline versatility into a pleasingly simple package.

The Eero is available now as a frameset only in select sizes with full availability to follow in February 2021.

Arc8 Eero gravel bike key stats

Arc8 Eero gravel bike with 1x Shimano GRX groupset
The bike cuts a very road-like silhouette. - Jack Luke / Immediate Media
  • 1,120g claimed weight for medium painted frame, 950g unpainted
  • 425g claimed weight painted fork, 380g unpainted
  • 8.36kg (measured) for 2× Shimano GRX build
  • 700c × 50mm tyre clearance
  • ISO-threaded bottom bracket
  • Mudguard and rack mounts
  • 1,990 CHF
  • Custom paint options available

Who is the Ar8 Eero for?

Gravel bikes run across a broad spectrum: from pseudo-mountain bikes with suspension tech to all-out aero gravel race wagons, the ‘gravel’ label encompasses it all.

The Eero sits towards the racier end of that spectrum, with an aggressive aero-profiled silhouette that is designed for “riders who like to go fast on unpaved roads”.

It is also billed as a bike that could act as a viable replacement for a road bike with “minor to no compromises”.

Indeed, unlike many modern gravel bikes, the Eero is very road-like in appearance, with a fairly aggressive fit, no fussy suspension-like tech or super-slack geometry numbers.

Arc8 Eero gravel bike with 1x Shimano GRX groupset
Arc8 makes no specific claims about the aero qualities of the Eero, but the influence from the brand's Escapee endurance road bike can be clearly seen. - Jack Luke / Immediate Media

Though no specific claims are made about the aerodynamic – sorry, that should be Eerodynamic – qualities of the frameset, the bike is based on the same “aerodynamic tube shapes” seen on the brand’s Escapee endurance road bike.

The Eero joins a growing cohort of aero-adjacent gravel bikes and components, and we predict it could be one of the big trends of 2021.

As a tasty aside, Arc8 adds that the aero-friendly profiling of the tubes means that less mud collects on the down tube compared to a traditional round or boxier shape.

Like seemingly every new bike launched in the past year, the Eero features dropped seatstays for improved rear-end compliance.

Arc8 Eero gravel bike with 1x Shimano GRX groupset
The cutout increases tyre clearance and, Arc8 claims, improves rear-end compliance. - Jack Luke / Immediate Media

It is also claimed that the cutout near the base of the seat tube not only improves tyre clearance and aero qualities but also allows it to “absorb more vibrations”, improving comfort further.

Compared to the Escapee, the head tube stiffness of the Eero is claimed to be 4 per cent higher. While the bottom bracket stiffness of the bike is claimed to be 5 per cent greater than the Escapee.

More than just a go-fast gravel rocket

This focus on all-out speed is nicely balanced with exceptionally generous tyre clearance and features that will also make it suitable for year-round miles on the road and bikepacking. To start, the bike has clearances for 700c tyres up to 50mm-wide.

50mm is at the upper end of the gravel tyre spectrum and, if you require anything larger, you should probably just ride a mountain bike instead.

Arc8 Eero gravel bike with 1x Shimano GRX groupset
The straight driveside chainstay can be clearly seen here. - Jack Luke / Immediate Media

Dropped chainstays are often used to maintain tyre and chainring clearance on gravel bikes. Arc8 claims this design is less stiff and not “easy on the eyes”.

To maintain a straight driveside chainstay, the Eero’s down tube is extended beyond the bottom bracket shell. This allows it to run the chainstay in a clean straight line from below the bottom bracket all the way to the rear dropout.

The bike features two sets of bottle cage mounts inside the main triangle and an additional set slung beneath the down tube. There is also a bento box/snack pack mount on the top tube.

Arc8 Eero gravel bike with 1x Shimano GRX groupset
We are delighted to see mudguard mounts on this bike. - Jack Luke / Immediate Media

Most notably, the bike also has provision to mount full-cover mudguards and a rear rack.

Although the situation has undoubtedly improved in recent years, seeing a full complement of mounts is still relatively rare in the world of high-end race-focused gravel and road bikes, and deserves heaps of praise.

If you’re not running mudguards, the neat and pleasingly simple seatstay bridge is removable. This bolts between two eyelets on the inside face of the seatstays.

The frameset is compatible with both 1× and 2× drivetrains, featuring a removable front derailleur mount. Swappable ports also allow you to switch between electronic and mechanical groupsets.

Arc8 Eero gravel bike with 1x Shimano GRX groupset
Hooray for threaded bottom brackets. - Jack Luke / Immediate Media

The frameset is built around an ISO-threaded (‘BSA’) bottom bracket shell. While press-fit solutions can work well, there’s no denying that a threaded bottom bracket is far easier to maintain for home mechanics.

Interestingly, the Eero press pack states that Arc8 decided against a T47-threaded shell because an ISO-threaded shell is lighter and compatible with Shimano bottom brackets.

All cables and hoses are internally routed on the bike, entering the front of the custom alloy stem, which is included with framesets.

The stem uses a clamping system that is quite unlike anything we’ve seen before.

The body of the stem holds a wedge that cradles the rear portion of the clamping area of the handlebars. A pair of U-shaped clamps that sit on either side of the body of the stem are then tightened against this wedge using 3mm grub screws. This in turn clamps the bar in place.

Most multi-tools are too chunky to access these screws, so if you want to adjust it in the field, you’ll need to take along a small ratchet or a suitably long hex key.

Finally, if you’re wondering about where ‘Eero’ comes from, the bike is named after Eero Hämäläinen – a Finnish rally driver who is said to have been a “superhero on gravel”. We assume that was in a car.

Ar8 Eero gravel bike pricing and availability

Arc8 Eero gravel bike with 1x Shimano GRX groupset
We are absolutely in love with this wonderful graduated pink paint job. - Jack Luke / Immediate Media

A single Campagnolo Ekar build with matching Shamal DB wheels is available via select Arc8 dealers in Switzerland but, for everyone else, the Eero is available as a frameset only for now.

This may change down the line, Arc8 says offering complete bikes has been delayed due to (understandable) current shipping and logistics hurdles. It is assessing the situation and may offer complete bikes in 2021.

Ar8 Eero grey frame
This grey/blue frameset will be available at launch. - Arc8

Right now, a limited-edition grey/blue frameset in sizes medium and large is available. Blue, pink and custom paint options will be available in all sizes from February 2021.

The frameset costs 1,990 CHF (approx £1,630 / $2,170). This price is inclusive of shipping. Exact international pricing for your territory will be calculated when you visit the Arc8 website.

For that price, you get a seat clamp, thru-axles, a headset, headset bung, matching alloy bar and stem, the removable front derailleur mount, and adaptors for running mechanical groupsets or Di2 drivetrains.

Arc8 Eero gravel bike with 1x Shimano GRX groupset
A Faserwerk seatpost is available as an optional upgrade for the bike. - Jack Luke / Immediate Media

An optional Faserwek Wuthocker seatpost is also available for 149 CHF. Any other normal 27.2mm diameter seatpost will also work.

We have the tasty 1× GRX build in for review and will be reporting back on how we get on with the Eero once we’ve had time to put some miles in on the bike.