A size-by-size geometry profile with manufacturer provenance and RideDNA consistency-audit context. Use the complete table to compare fit and handling before opening the interactive tools.
Source: Manufacturer geometry source
Provenance: published is present in the manufacturer data; derived is calculated by RideDNA; manual is a staff-entered reference rather than a manufacturer-chart value. “Not published” means the manufacturer did not provide a value for that size.
| Size | Stack | Reach | HTA | STA | ETT | Chainstay | Wheelbase | Front center | BB drop | Trail | Fork offset | Audit context |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 48 | 554 mm published | 380 mm published | 71.5 ° derived | 74.0 ° derived | Not published | 430 mm derived | 1026 mm derived | 606 mm published | 72 mm derived | 52.0 mm derived | 48 mm derived | green |
| All 3 consistency checks passed | ||||||||||||
| 52 | 573 mm published | 390 mm published | 71.5 ° derived | 73.5 ° derived | Not published | 430 mm derived | 1033 mm derived | 613 mm published | 70 mm derived | 61.7 mm derived | 48 mm derived | green |
| All 3 consistency checks passed | ||||||||||||
| 54 | 591 mm published | 400 mm published | 71.5 ° derived | 73.0 ° derived | Not published | 430 mm derived | 1048 mm derived | 628 mm published | 70 mm derived | 62.7 mm derived | 48 mm derived | green |
| All 3 consistency checks passed | ||||||||||||
| 57 | 610 mm published | 410 mm published | 71.5 ° derived | 73.0 ° derived | Not published | 430 mm derived | 1064 mm derived | 644 mm published | 70 mm derived | 62.9 mm derived | 48 mm derived | green |
| All 3 consistency checks passed | ||||||||||||
| XS | 536 mm published | 371 mm published | 71.0 ° derived | 74.0 ° derived | Not published | 430 mm derived | 1016 mm derived | 596 mm published | 72 mm derived | 54.8 mm derived | 48 mm derived | green |
| All 3 consistency checks passed | ||||||||||||
Overall consistency: green. This context is shown alongside the table so a rider can distinguish a complete published specification from a value that RideDNA had to derive or could not independently verify.
The Colnago G4-X geometry audit shows all forward-model checks passing with 0.0mm deltas across all five sizes. However, the manufacturer has withheld effective top tube length (ETT), forcing the engine to derive it from the published reach, stack, and seat tube angle values. This derivation renders the reach check algebraically circular — it confirms formula consistency only, not independent verification of the published reach. Front center is the sole genuinely independent check in this audit. By withholding effective top tube length, the manufacturer prevents independent scrutiny of its geometry claims and denies consumers the data they need to evaluate handling characteristics or make meaningful comparisons with competing models. This is not an obscure technical figure — it is a standard dimension routinely published by competing manufacturers. This is a deliberate choice, not a technical limitation. Consumers cannot fully assess fit, predict handling, or compare this bicycle on equal terms without it. Transparency about geometry is not optional: it is the minimum standard a manufacturer owes to buyers making thousands-of-dollars purchasing decisions.