Geometry ?
Boma Allumer Disc Ct Ad 2026 geometry in sizes S-450–L-500: stack 535–560 mm, reach 374–381 mm, head angle 72.1–73°.
| S-450 | M-475 | L-500 | |
|---|---|---|---|
| Stack | 535 mm | 546 mm | 560 mm |
| Reach | 374 mm | 377 mm | 381 mm |
| Head angle | 72.1° | 72.8° | 73° |
| Seat angle | 74.6° | 74.2° | 73.7° |
| Seat tube (c-t) | 450 mm | 475 mm | 500 mm |
| Head tube | 130 mm | 140 mm | 155 mm |
| Top tube (effective) | 520 mm | 531 mm | 545 mm |
| BB drop | 72 mm | 72 mm | 70 mm |
| Chainstay | 410 mm | 410 mm | 410 mm |
| Wheelbase | 974 mm | 974 mm | 982 mm |
| Fork offset | 45 mm | 45 mm | 45 mm |
Source: boma.jp, checked 12 Nov 2026 · bar position: worked out from published data
Stock build
I don’t have the build for each size yet.
Frames with similar geometry
Stack and reach within 12 mm of size S-450 (stack 535 / reach 374 mm).
Allebike Arrow (2026)size S · stack 534 / reach 374 mmEnigma Elan (2026)size 52 · stack 535 / reach 375 mmFactor Monza (2026)size 52 · stack 535 / reach 373 mmFactor O2 VAM (2026)size 52 · stack 535 / reach 373 mmLitespeed Spezia (2026)size S · stack 535 / reach 375 mmLitespeed Spezia FI (2026)size S · stack 535 / reach 375 mm
Stack and reach within 12 mm of size M-475 (stack 546 / reach 377 mm).
Baum Orbis (2026)size 52 · stack 545 / reach 377 mmColuer Invicta Disc (2026)size S · stack 546 / reach 378 mmEnigma Eikon (2026)size 53 · stack 547 / reach 377 mmSunpeed Victory (2025)size M · stack 547 / reach 377 mmBisan RX 9500 (2026)size 50 cm · stack 546 / reach 378 mmBoardman SLR (alloy, rim brakes) (2021)size SM · stack 547 / reach 378 mm
Stack and reach within 12 mm of size L-500 (stack 560 / reach 381 mm).
Enigma Excel (2026)size 54 · stack 559 / reach 380 mmKHS Flite 600 (2025)size M · stack 559 / reach 380 mmPinarello Dogma X (2027)size 53 · stack 559 / reach 379 mmRibble Ultra-Road (2026)size M · stack 560 / reach 379 mmSeven A-738 Allroad (Standard Fit) (2026)size 54 · stack 560 / reach 383 mmAppalanchia R14 (2026)size 510 · stack 558 / reach 380 mm
Spotted a mistake or a missing build? Let me know.
Are you the manufacturer, or do you sell this bike? I’m missing 5 values for this model’s stem and bars. Add them