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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 44 | 543 mm published | 353 mm published | 69.3 ° derived | 75.0 ° derived | 503 mm derived | 418 mm derived | 994 mm published | 589 mm published | 80 mm derived | 76.0 mm published | 52 mm published | green |
| All 5 consistency checks passed | ||||||||||||
| 49 | 549 mm published | 363 mm published | 70.8 ° derived | 74.0 ° derived | 523 mm derived | 418 mm derived | 992 mm published | 587 mm published | 80 mm derived | 66.0 mm published | 52 mm published | green |
| All 5 consistency checks passed | ||||||||||||
| 52 | 566 mm published | 370 mm published | 71.5 ° derived | 74.0 ° derived | 534 mm derived | 418 mm derived | 988 mm published | 593 mm published | 80 mm derived | 62.0 mm published | 52 mm published | yellow |
| 1 of 5 checks flagged — Trail Reconciliation shows 2.1mm discrepancy | ||||||||||||
| 54 | 585 mm published | 381 mm published | 72.3 ° derived | 74.0 ° derived | 550 mm derived | 420 mm derived | 1005 mm published | 598 mm published | 78 mm derived | 61.0 mm published | 47 mm published | yellow |
| 1 of 5 checks flagged — Stack Reconciliation shows 2.1mm discrepancy | ||||||||||||
| 56 | 605 mm published | 389 mm published | 73.0 ° derived | 73.5 ° derived | 569 mm derived | 420 mm derived | 1012 mm published | 604 mm published | 78 mm derived | 57.0 mm published | 47 mm published | yellow |
| 1 of 5 checks flagged — Stack Reconciliation shows 2.3mm discrepancy | ||||||||||||
| 58 | 630 mm published | 397 mm published | 73.0 ° derived | 73.5 ° derived | 584 mm derived | 423 mm derived | 1031 mm published | 620 mm published | 78 mm derived | 57.0 mm published | 47 mm published | green |
| All 5 consistency checks passed | ||||||||||||
| 61 | 665 mm published | 403 mm published | 73.5 ° derived | 73.5 ° derived | 600 mm derived | 423 mm derived | 1042 mm published | 631 mm published | 78 mm derived | 54.0 mm published | 47 mm published | green |
| All 5 consistency checks passed | ||||||||||||
Overall consistency: yellow. 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.
Geometry reconciliation applies a 48mm Future Shock steerer extension correction to both stack and reach before comparison against the engine's forward-model calculations. The Specialized Roubaix SL8 specification shows strong overall consistency with the RideDNA forward-model geometry. Stack shows 2.1–2.3mm data inaccuracies in the published values on sizes 54 and 56; all other sizes reconcile within ±1mm engineering tolerance. Reach, wheelbase, and front center reconcile within ±1mm engineering tolerance across all seven sizes. Trail shows a 2.1mm data inaccuracy in the published value on size 52; all other sizes reconcile within ±1mm engineering tolerance.