Good to know: Integrated cockpit
Integrated cockpit (a one-piece bar and stem) on at least one build. Changing the length means replacing the whole cockpit, and not every length exists. Check which length the bike actually ships with before you buy.
Geometry ?
Radon Spire 2026 geometry in sizes XS–XL: stack 508–588 mm, reach 379–406 mm, head angle 71.5–73.5°.
| XS | S | M | L | XL | |
|---|---|---|---|---|---|
| Stack | 508 mm | 523 mm | 542 mm | 563 mm | 588 mm |
| Reach | 379 mm | 384 mm | 388 mm | 397 mm | 406 mm |
| Head angle | 71.5° | 72.5° | 73° | 73.5° | 73.5° |
| Seat angle | 75° | 74° | 73.5° | 73.2° | 73° |
| Seat tube (c-t) | 460 mm | 490 mm | 510 mm | 530 mm | 560 mm |
| Head tube | 110 mm | 120 mm | 140 mm | 160 mm | 180 mm |
| Top tube (effective) | 515 mm | 536 mm | 548 mm | 565 mm | 587 mm |
| BB drop | 69 mm | 69 mm | 69 mm | 69 mm | 69 mm |
| Chainstay | 408 mm | 408 mm | 408 mm | 408 mm | 408 mm |
| Wheelbase | 975 mm | 975 mm | 981 mm | 994 mm | 1010 mm |
| Stock build by size | |||||
| Cranks | 170 mm | 172.5 mm | 172.5 mm | 175 mm | 175 mm |
| Stem | 90 mm | 90 mm | 100 mm | 100 mm | 110 mm |
| Bar width | 400 mm | 400 mm | 420 mm | 420 mm | 440 mm |
| Seatpost setback | 18 mm | 18 mm | 18 mm | 18 mm | 18 mm |
Source: radon-bikes.de, checked 3 Nov 2026 · bar position: worked out from published data
Stock build
Spire 10.0 €4,499
- Groupset
- SRAM Force AXS E1, 12-speed
- Shifters
- SRAM Force AXS E1 HRD, 2×12
- Cranks
- Sram Force AXS Spindle Power Meter E1, 48/35T
- Handlebar
- SPIRE Aero Carbon stem-handlebar unit
- Seatpost
- SPIRE Carbon Seatpost, 350 mm
- Saddle
- Selle Italia SLR Boost Superflow Kit Carbonio
- List price
- €4,499 (radon-bikes.de, 3 Nov 2026)
Spire 9.0 €3,699
- Groupset
- Shimano ULTEGRA Di2 RD-R8150, 12-speed
- Shifters
- Shimano ULTEGRA Di2 ST-R8170, 2×12
- Cranks
- Shimano ULTEGRA FC-R8100, 52/36T
- Handlebar
- SPIRE Aero Carbon stem-handlebar unit
- Seatpost
- SPIRE Carbon Seatpost, 350 mm
- Saddle
- Selle Italia SLR Boost TM Superflow
- List price
- €3,699 (radon-bikes.de, 3 Nov 2026)
Spire 8.0 €2,799
- Groupset
- Shimano 105 Di2 RD-R7150, 12-speed
- Shifters
- Shimano 105 Di2 ST-R7170, 2×12
- Cranks
- Shimano 105 FC-R7100, 52/36T
- Handlebar
- SPIRE Aero Carbon stem-handlebar unit
- Seatpost
- SPIRE Carbon Seatpost, 350 mm
- Saddle
- Selle Italia Model, Superflow
- List price
- €2,799 (radon-bikes.de, 3 Nov 2026)
Source for all builds: radon-bikes.de, checked 3 Nov 2026
Frames with similar geometry
Stack and reach within 12 mm of size XS (stack 508 / reach 379 mm).
Stack and reach within 12 mm of size S (stack 523 / reach 384 mm).
Stack and reach within 12 mm of size M (stack 542 / reach 388 mm).
Stack and reach within 12 mm of size L (stack 563 / reach 397 mm).
Stack and reach within 12 mm of size XL (stack 588 / reach 406 mm).
Spotted a mistake or a missing build? Let me know.
Are you the manufacturer, or do you sell this bike? I’m missing 2 values for this model’s stem and bars. Add them