The Tarmac SL8, by a small margin. External wind-tunnel data cited by reviewers puts the SL8 at roughly 209 W at 45 km/h — only a few watts behind the Cervélo S5 (205 W) and Canyon Aeroad (208 W). The Canyon Ultimate Gen 5 claims a 10-watt frameset gain over the previous Ultimate, but it's not a dedicated aero bike — Canyon positions the Aeroad for that job.

In real-world terms, the gap between them is small enough that wheel choice and tire setup matter more than frame for most riders below 35 km/h.

Effectively a tie at the top end. Canyon's flagship CFR Di2 has been weighed at around 6.4 kg by BikeRadar; Specialized claims a 6.67 kg S-Works in size 56. Both have stiff bottom brackets and reinforced head tubes, and both reward out-of-saddle attacks.

Reviewers consistently call the Ultimate 'insatiable' on climbs and the Tarmac SL8 'electric.' On a 30-minute climb, the difference between them is in the noise.

Canyon Ultimate: 33 mm on all Gen 5 builds, front and rear.

Specialized Tarmac SL8: 32 mm officially.

Neither is a gravel bike. For mixed-surface use, look at the Canyon Endurace or Specialized Roubaix — both clear 38 mm or wider.

On the spec sheet, often yes. A $5,999 Canyon Ultimate CF SLX 8 ships with Shimano Ultegra Di2, a 4iiii Precision power meter, and DT Swiss ARC 1400 38 mm carbon wheels. The closest Tarmac SL8 Expert at $6,599 also runs Ultegra Di2 but pairs it with shallower Roval wheels.

What you give up with Canyon: a local dealer for fit, demos, warranty, and any service you can't do yourself. For mechanically confident riders who know their size, the Canyon math is hard to argue with. For riders who want hand-holding, the Specialized premium buys real-world support.

The Canyon CP0048 is one of the most adjustable integrated cockpits on the market — 50 mm of width adjustment and 20 mm of height adjustment, with interchangeable drops on some builds, all without cutting the steerer or bleeding hoses.

The Tarmac's Roval one-piece cockpit (on S-Works and Pro builds) is stiffer and more aero, but stem length and bar width are fixed at purchase. Changing them post-purchase typically runs $450+ for the part plus labor for a hose bleed. The Expert builds use a two-piece alloy bar and stem instead, which is far more adjustable but less integrated.

Effectively no, in current trim. Both Gen 5 Ultimate and SL8 frames are routed for electronic groupsets — the entry-level builds on each ship with Shimano 105 Di2 or SRAM Rival AXS, not mechanical. If you want a mechanical drivetrain, you're looking at older generations on the used market.

Surprisingly different despite both being race bikes. At fit-picked sizes for the same rider — Canyon size S vs Tarmac size 54 — the Canyon sits 5 mm lower (539 mm vs 544 mm stack) and 6 mm longer (390 mm vs 384 mm reach). The Canyon's wheelbase is 5 mm longer (983 mm vs 978 mm), which favors high-speed stability.

The Tarmac is the more upright, more compact race position; the Ultimate is longer and lower in the same nominal fit. Less flexible riders may find the Tarmac more comfortable; riders with longer torsos may prefer the Canyon.

Both frames come with a lifetime frame warranty to the original owner against manufacturing defects, and both offer crash-replacement pricing. The practical difference is the service path: a Canyon warranty claim goes through Canyon directly, ships back to the brand, and depends on Canyon's turnaround. A Specialized warranty claim goes through any authorized Specialized dealer, which typically means faster local resolution.