- Argon 18 Krypton Pro
- XXS
- Stack 523, Reach 357
- Specialized Tarmac SL9
- 49
- Stack 514, Reach 375
Stack: 9 mm lower
Reach: 18 mm longer
Argon 18 Krypton Pro vs Specialized Tarmac SL9: which bike is right for you?
Compare ride character, intended rider, geometry, and fit. Add your measurements to see which bike suits you better and which size to choose on each.
Fit verdict: the frame positions differ enough to matter. Compare the geometry below, then use your measurements to identify the safer size and setup.
In one look
Argon 18 Krypton Pro: all-road geometry. Specialized Tarmac SL9: race geometry.
- Across matched sizes, the frame fronts of Argon 18 Krypton Pro and Specialized Tarmac SL9 differ by only a few millimetres. Stem and spacer choices will have more effect on handlebar position.
- The frame front of Specialized Tarmac SL9 is about 17 mm longer. Handlebar position also depends on the stem and spacers.
These two split on cockpit, maximum tyre clearance; the sourced values are below. What each difference means for your size, your setup and the riding you describe is in the full comparison.
- Argon 18 Krypton Pro
- Two-piece integrated
- Specialized Tarmac SL9
- One-piece integrated bar and stem
A one-piece cockpit is cleaner and faster, but changing bar width or stem length means buying a whole new unit.
- Argon 18 Krypton Pro
- 40 mm
- 40 mm with a 1x drivetrain
- 35 mm with a 2x drivetrain
- Specialized Tarmac SL9
- 32 mm
Tyre width decides which surfaces stay comfortable. A few millimetres is the difference between staying on tarmac and being able to drop onto gravel without a second bike.
- Price
Specialized Tarmac SL9 is the dearer of the two, going by the cheapest build you can buy of each; Argon 18 Krypton Pro starts lower.
Subjective findings from independent tests on stock or near-stock builds. Tyres, pressure and size change how a frame feels.
We compare differences at frame and model level. Components, current price, and availability depend on the exact build and seller.
What do you need from this comparison?
Start with the decision you are making. We will ask only for the details needed to answer it.
Step 1/1
What are you trying to understand?
Your answer decides which questions follow and what the result focuses on.
Fit and size differences
Geometry can separate these bikes: matched sizes create a meaningfully different position.
Typical difference across matched sizes: frame front height 2 mm, forward length 17 mm.
For a personal answer, the fit-and-size path uses your measurements to show only the relevant frame sizes. The full chart remains available as a reference.
View geometry for every size
How do Argon 18 Krypton Pro and Specialized Tarmac SL9 sizes compare?
See the closest size matches and the differences in stack, reach, and riding position.
- Argon 18 Krypton Pro
- XS
- Stack 543, Reach 367
- Specialized Tarmac SL9
- 54
- Stack 544, Reach 384
Stack: practically identical
Reach: 17 mm longer
- Argon 18 Krypton Pro
- S
- Stack 563, Reach 377
- Specialized Tarmac SL9
- 56
- Stack 565, Reach 395
Stack: practically identical
Reach: 18 mm longer
- Argon 18 Krypton Pro
- M
- Stack 584, Reach 386
- Specialized Tarmac SL9
- 58
- Stack 591, Reach 402
Stack: 7 mm taller
Reach: 16 mm longer
- Argon 18 Krypton Pro
- L
- Stack 605, Reach 395
- Specialized Tarmac SL9
- 61
- Stack 612, Reach 408
Stack: 7 mm taller
Reach: 13 mm longer
- Argon 18 Krypton Pro
- XL
- Stack 628, Reach 406
- Specialized Tarmac SL9
- 61
- Stack 612, Reach 408
Stack: 16 mm lower
Reach: practically identical
The same size label can create a different position on each frame. Stack and reach are one part of the decision; the personalized comparison connects them to your body and each bike’s ride character.
FAQ
- Can the same rider take different sizes on these two bikes?
- Yes. Frame labels are not standardized, so the same rider may need different sizes. This comparison deliberately avoids a generic matched-size answer and hands your measurements to Bike Fit instead.
- Which frame has the higher front: Argon 18 Krypton Pro or Specialized Tarmac SL9?
- Across matched sizes, the frame fronts of Argon 18 Krypton Pro and Specialized Tarmac SL9 differ by only a few millimetres. Stem and spacer choices will have more effect on handlebar position.
TrainCraft training
Prepare for a goal or an event
Read training guides by goal and preparation roadmaps for cycling events, and use free structured workouts with .zwo export. Training plans are part of PRO. Adaptive plan changes that you review and apply are part of PRO AI.