Avona Callis 32 Frameset | 32-Inch Wheel Gravel Race Bike

Avona Callis 32: bigger wheels, faster gravel

The Avona Callis 32 is one of the first gravel race bikes built from the ground up around 32-inch wheels. They took everything that made the original Callis fast (aero, light and properly compliant) and asked a simple question: what happens if the wheels get bigger? Their answer, after outdoor and wind tunnel testing, is a saving of 8 to 16 watts at 35 km/h, depending on terrain and tyre.

The frameset comes with the Faserwerk Luftschneider integrated cockpit (pick your width and length above), the Faserwerk Wuthocker Aero seatpost in your choice of offset, and an Enduro stainless headset with a lifetime warranty.

Why 32-inch wheels?

For the last decade, gravel bikes have been built around 700c (the same 622mm rim as a 29er mountain bike). A 32-inch wheel uses a 686mm rim, so with a 50mm tyre the whole wheel is roughly 6 to 7cm taller. That extra size changes how the bike meets the ground:

It rolls over things instead of into them. A bigger wheel hits a rock, root or pothole at a shallower angle, so less of your speed is lost on every bump. On gravel, where the bumps never stop, that adds up fast.
A longer contact patch. The tyre's footprint gets longer and narrower, which deforms the tyre less as it rolls (lower rolling resistance) and puts more rubber on the ground for grip and braking.
More momentum, calmer handling. Bigger wheels carry speed better and feel more settled at pace, so loose corners and chattery descents feel less frantic.
The trade-offs. Bigger wheels mean a little more frontal area (aero drag), longer levers working on the frame and fork, and less room to fit everything in. That's why this needed a new frame, not just bigger tyres.

The design challenge

Avona didn't just stretch the Callis. They set themselves six problems to solve:

Fit: bigger wheels push stack height up and bring your toes closer to the front tyre. Geometry had to keep a race position achievable.
Packaging: less space between the wheels, so storage, bottles and tyre clearance all had to be rethought.
Handling: they wanted it to stay lively, not turn into a barge. A 70° head angle with 60mm offset gives 82mm of trail, and the chainstays stay short at 440mm.
Weight: the goal was a bike that climbs faster than the 700c Callis, not slower.
Aerodynamics: the rolling resistance gain had to beat the extra aero drag at every speed you'd see in a gravel race.
Stiffness: a longer fork, longer stays and bigger wheels all add leverage. Compared to the 700c Callis, the Callis 32 is 7% stiffer torsionally and 12% stiffer at the bottom bracket, with the same vertical compliance.

The numbers: tested, not guessed

Outdoor testing: Avona, and separately independent tester John Karrasch, ran back-to-back comparisons using the virtual elevation method (also called the Chung method, which works out drag from power, speed and elevation data on a real course). Rolling resistance savings at 29 km/h:

Pavement: 7 W
Category 1 gravel: 11 W
Category 2 gravel: 13 W
Category 3 gravel: 11 W

Wind tunnel: to see how much aero they'd given up, they went to the GST wind tunnel and tested the same wheels and tyres in both sizes. The difference was only 1.2 to 3.1 W at 35 km/h (depending on wheels). Lose 2 or 3 watts to the wind, gain 7 to 13 back from the ground. That's a trade we'd take every day.

Not just for racers

You don't need to care about watts to feel the difference. More grip and stability mean more confidence when the surface turns sketchy, and the extra roll-over and momentum make the whole ride calmer. If your idea of gravel is big days, new roads and coffee stops, the Callis 32 makes those kilometres easier too.

One size, two fits

The Callis 32 comes in Medium, Large and X-Large, and the seatpost offset you choose decides how it fits:

0mm offset + longer stem: a progressive, forward race position (about 76° effective seat angle).
15mm offset: the in-between option (about 75°).
30mm offset + shorter stem: a traditional road-style position (about 74°).

The forward position often means going up a frame size from what you'd normally ride, so shorter riders can fit a Medium if they're happy with a forward fit and a taller standover. Rough rider height guide (see the fit guide images for the full chart):

Medium: approx. 164-177cm traditional / 166-180cm forward
Large: approx. 174-188cm traditional / 176-190cm forward
X-Large: approx. 184-198cm traditional / 186-200cm forward

Not sure which size or offset suits you? Send us your height and current bike setup and we'll help you choose.

The Inside Line:
Every few years someone says "bigger wheels" and everyone rolls their eyes. Then 29ers happened. Avona did the homework here: wind tunnel, real-world testing and a frame designed around the wheel, not a 700c frame with extra clearance. If you race gravel, it's free speed. If you don't, it's free comfort. Either way, you'll be the one at the start line everyone wants to talk to.

Features:

Built for 32-inch (686mm) wheels
Frame weight: 898g (painted)
Fork weight: 409g (painted)
Frameset weight incl. all parts, painted: 1728g
Tyre clearance: up to 55mm (with 6mm clearance)
Hub spacing: 12x148mm Boost rear, 12x110mm Boost front
Boost chainline, single chainring only
UDH (Universal Derailleur Hanger), compatible with SRAM Transmission
Brakes: flat mount 160mm, with the option to go to 180mm
Bottom bracket: BSA threaded
Integrated frame storage, plus room for two large bottles
Headset: Enduro 440C stainless bearings with lifetime warranty
Seatpost and sealed headset cap shared with the Avona Velum and Callis 700c
Stiffness vs Callis 700c: +7% torsional, +12% bottom bracket, same vertical compliance
Colours: Deep Olive, Carbon Clear Coat, Ultra Violet

Geometry (Medium / Large / X-Large):

Stack: 578 / 598 / 618mm
Reach: 391 / 398 / 405mm
Seat tube length: 460 / 490 / 530mm
Top tube (horizontal): 534 / 546 / 558mm
Head tube length: 80 / 101 / 122mm
Head tube angle: 70°
Seat tube angle (actual): 72.6°
Fork offset: 60mm / Fork length (A-C): 438mm / Trail: 82mm
BB drop: 112mm
Chainstay length: 440mm
Standover: 808 / 834 / 863mm
Wheelbase: 1050 / 1064 / 1078mm
Stem length: 75-120mm / Handlebar width: 380-420mm (reach 70mm, drop 125mm)

Package Contents:

Avona Callis 32 carbon frame and fork
Faserwerk Luftschneider integrated cockpit (size as selected) - more info
Faserwerk Wuthocker Aero seatpost, 400mm (offset as selected)
Enduro ACB 4545 stainless headset
Faserwerk thru axles (front 12x110mm, rear 12x148mm)

Looking for a complete build?

We can build your Callis 32 into a complete bike to suit how you ride, from SRAM Rival to Red, with wheels and tyres to match. Reach out to our team to discuss options.

Avona Callis 32 - Frameset