Pinch to Zoom

Rotate screen for larger image

Aethos Expert

12 Reviews

Aethos: Billions of calculations in the pursuit of one thing—the perfect ride. It’s…

We deliver! Just say when and how.

Voted Best Brand 5 Years in a Row

#1 Again: 2023 Gran Fondo Awards

The riders have spoken! For the fifth year in a row, Specialized has been crowned the #1 “Drop Bar Bike Brand” in the prestigious Gran Fondo Best Brand Awards for 2023. We innovate for riders, and year after year, our bikes are loved by the most discerning riders. Thank you!

The lightest disc road frame ever: The Specialized Aethos

Product Details

Aethos: Billions of calculations in the pursuit of one thing—the perfect ride. It’s more than just a motto, it’s a philosophy. The Aethos has been designed to straddle the line between a perfected ride quality, extreme light weight, and undeniable style, and this Expert model is no exception.

With quick-shifting, low-maintenance Ultegra Di2 electronic shifting and hydraulic disc brakes paired with bomb-proof Roval C38 Disc carbon wheels, you have the perfect steed to get you out on the road.

The Aethos frame has been designed with the perfect combination of ultimate ride feel, light weight, and style—from accelerating up steep pitches and descending technical descents, to all-day saddle comfort on even the longest coffee rides, the Aethos hits the mark. But how, you ask? By reinventing the traditional road shape found on bikes of the past, we’ve subtly altered these shapes to deliver massive gains in stiffness and balance, all without affecting weight or durability. Pair that with an entirely new layup and process that we’ve perfected over multiple decades and you have the lightest frame out there (585 grams, S-Works, size 56cm). The Aethos is more than just a new bike, it’s the first of a new breed.
A featherweight frame is useless without confidence-inspiring ride characteristics, which is why we’ve developed the Aethos to have the perfect balance of front and rear stiffness combined with exceptional ride quality. By studying the flexing and breathing of carbon fiber, we were able to discover groundbreaking findings about how forces flow through frames. Just a few pedal strokes and you’ll realize this sublime ride sets a new standard.
Every detail, from the derailleur hangers to the fork expander plug have been designed with style, weight, and durability in mind. We’ve also spec’d it with Roval’s all-new Alpinist carbon seatpost, further saving weight and improving ride characteristics. Everything in pursuit for the perfect ride.

Technical Specifications

Frameset

Frame

Aethos FACT 10r Carbon, Rider First Engineered™, Threaded BB, 12x142mm thru-axle, flat-mount disc

Suspension

Fork

FACT Carbon, 12x100mm thru-axle, flat-mount disc

Brakes

Front Brake

Shimano Ultegra R8170, hydraulic disc

Rear Brake

Shimano Ultegra R8170, hydraulic disc

Drivetrain

Shift Levers

Di2 Shimano Ultegra R8170, hydraulic disc

Front Derailleur

Di2 Shimano Ultegra R8150, braze-on

Rear Derailleur

Di2 Shimano Ultegra R8150, 12-speed

Cassette

Shimano Ultegra, 12-speed, 11-30t

Chain

Shimano XT M8100, 12-speed w/ quick link

Crankset

Shimano Ultegra R81000

Chainrings

52/36T

Bottom Bracket

Shimano Threaded BSA BB

Wheels & Tires

Front Wheel

Roval C38, 21mm internal width carbon rim

Front Tire

S-Works Turbo, 120 TPI, folding bead, BlackBelt protection, 700x26mm

Rear Tire

S-Works Turbo, 120 TPI, folding bead, BlackBelt protection, 700x26mm

Rear Wheel

Roval C38, 21mm internal width carbon rim

Inner Tubes

Turbo Ultralight, 48mm Presta valve

Cockpit

Stem

Specialized Pro SL, alloy, 4-bolt

Handlebars

Specialized Expert Shallow Drop, alloy, 125mm drop x 75mm reach

Tape

Supacaz Super Sticky Kush

Saddle

Body Geometry Power Expert

SeatPost

Roval Alpinist Carbon Seatpost

Seat Binder

Specialized Alloy, 30mm

* Weights based on production painted frames as pictured. Actual weights will vary based on colorway, frame size, and component variation. Specifications are subject to change without notice.

Geometry

	49	52	54	56	58	61
Crank Length	165mm	170mm	172.5mm	172.5mm	175mm	175mm
Handlebar Width	380mm	400mm	420mm	420mm	440mm	440mm
Stem Length	80mm	90mm	100mm	100mm	110mm	110mm
Saddle Width	155mm	155mm	143mm	143mm	143mm	143mm
Seatpost Length	300mm	300mm	360mm	360mm	360mm	360mm
Stack	514mm	527mm	544mm	565mm	591mm	612mm
Reach	375mm	380mm	384mm	395mm	402mm	408mm
Head Tube Length	109mm	120mm	137mm	157mm	184mm	204mm
Head Tube Angle	71.75°	72.5°	73°	73.5°	73.5°	74°
BB Height	266mm	266mm	268mm	268mm	268mm	268mm
BB Drop	74mm	74mm	72mm	72mm	72mm	72mm
Trail	63mm	58mm	58mm	55mm	55mm	52mm
Fork Length, Full	369mm	369mm	369mm	369mm	369mm	369mm
Fork Rake/Offset	47mm	47mm	44mm	44mm	44mm	44mm
Front Center	574mm	577mm	579mm	591mm	606mm	613mm
Chainstay Length	410mm	410mm	410mm	410mm	410mm	410mm
Wheelbase	973mm	975mm	978mm	991mm	1005mm	1012mm
Top Tube Length, Horizontal	508mm	531mm	540mm	562mm	577mm	595mm
Bike Standover Height	705mm	728mm	748mm	769mm	796mm	824mm
Seat Tube Length	431mm	462mm	481mm	504mm	532mm	567mm
Seat Tube Angle	75.5°	74°	74°	73.5°	73.5°	73°

Manual Downloads

Specialized Bicycle Owner's Manual (All Languages)

2022 Rider/Bike Weight Limits and Terrain Conditions

2021 Aethos User Manual

Trainer Usage Addendum to the Bicycle Owner's Manual

Rider Reviews

12 Reviews

04/12/2024

A Whole New Experience and Worth It

I chose the Aethos Expert after putting over 8000 miles on my gravel bike in the prior year. This was a significant move up from an alloy frame, not to mention the carbon wheels, too, and electronic shifting, hydraulic brakes. When I ride, it is a minimum of 20 miles, and often 40 to 60 miles, 5+ days a week. So, comfort was a must. My local bike shop and Specialized dealer in NYC was great -- Hilltop Bicycles. Thanks to their generosity, I test rode different Specialized and Aethos models and frame sizes. The perfect fit turned out to be the Aethos Expert. It is light, fast, subtly flexible, and very comfortable for long rides with some long, steep climbs out of the city. It is also responsive for dealing with the bumps, hazards, and unpredictable pedestrians and other riders in the city.

Name:: RSG

Helpful?

01/08/2024

Loving my Aethos

Moved over to the Specialized Aethos family from a Trek Emonda SLR7 after getting taken out by a car. I liked the Trek but wanted to try something different and most of the guys in my riding group are Specialized riders. The ride feel is awesome, I have 32mm tires on for the winter. I really like the bike and it is motivating me to get out and ride, even when it's 20 degrees outside. I'm only at 250 miles but so far so good.

Name:: Patrick

Helpful?

11/13/2023

Best bike I've ever owned

Would Recommend?: Yes!

Verified Buyer

Name:: Amy H.

Helpful?

06/27/2023

Best bike

I’ve had a Tarmac sl6 and sl7 this bike is way more comfortable. I am really enjoying this bike . It’s my most favorite bike ever.

Would Recommend?: Yes!

Name:: Jeffrey

Helpful?

05/13/2023

Amazing

This thing is amazing. I'm in love. Pricey, but worth it.

Would Recommend?: Yes!

Name:: Sam

Helpful?

01/12/2023

Awesome ride. It’s why you

Awesome ride. It’s why you buy Specialized. Nothing else to say!

Would Recommend?: Yes!

Verified Buyer

Name:: Guest G.

Helpful?

12/02/2022

Like Riding on a Cloud

I replaced a custom steel road bike that I had ridden for 27 years with an Aethos frameset which I built up with a mechanical Ultegra drivetrain. The bike weighs 15.5 pounds without pedals, with no exotic parts. It is like riding on air - comfortable, and fast up the hills. I'm still getting the hang of descending - it is so light I'm not yet as confident as I was on the custom steel bike. A phenomenal ride.

Would Recommend?: Yes!

Name:: David

Helpful?

09/21/2022

Above anything I have had before.

New Bike above anything I have had before, 12 speed Di2 for a roadie is very smooth and quiet when changing gears. Handles like a dream.

Would Recommend?: Yes!

Name:: Craig. S.

Helpful?

08/28/2022

Im in love with this bike.

I was suggested this bike after I broke my Tarmac frame and even when I spend money, I’m completely amaze how wonderful this bike is. Many think that because Specialized advertise this as comfortable, smooth ride is not going to be fast but is super fast indeed. I’m very happy with this one and I don’t really missed my previous Tarmac.

Would Recommend?: Yes!

Name:: Daniel S.

Helpful?

07/14/2022

One Fine bike

I purchased the Aethos Expert directly from Specialized this past March. I sold my excellent SL6 S-Works Tarmac in advance of the purchase with some trepidation. I have not been disappointed. The Aethos has proven to be every bit as fast, if not slightly faster, than the Tarmac in the flats. The Shimano 12 speed Ultegra Di2 is absolutely flawless and shifts instantly and smoothly. The bike tracks exceptionally well and the disc brakes are outstanding. The real test, however, was this past weekend when I took the Aethos on a hill ride for the first time with gradients of up to 13%. The bike ascended and descended flawlessly and I set 15 personal records on both long climbs and descents. I recommend this bike without hesitation.

Would Recommend?: Yes!

Name:: John

Helpful?

05/23/2022

Shimano>Sram

Came off a 16’ Giant defy advanced 2. Ive been looking for a solid upgrade for a couple years now. Went with the expert for the wheel set, longer battery life, and the shimano components look cleaner. The 12x Ultegra groupset is really nice. Holding the rear shifter for about 1.5 secs and it’ll shift 3 times. Or how one shift isnt making a big diff in cadence. Always a sweet spot with the 12x. Bike promotes riding faster and longer. I grew up racing bmx and this bike kinda reminds me of those days. Smashing pedals all day

Would Recommend?: Yes!

Name:: Kevin

Helpful?

05/09/2022

An Amazing Ride

The Aetheos Expert is everything that Specialized says it is. I went from a Roubaix to the Aetheos and the difference is dramatic. The automatic shifting is virtually instantaneous. The disc brakes are way better than caliper braking. The ride is smooth and fast. And perhaps most surprising, it is very, very easy to keep spotless. I was skeptical about whether the value would be there. It is. This is a spectacular bike!

Would Recommend?: Yes!

Name:: Steve

Helpful?