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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 47 | 510 mm published | 390 mm published | 71.0 ° derived | 73.0 ° derived | 546 mm derived | 420 mm derived | 1003 mm published | 596 mm published | 80 mm derived | 68.0 mm published | 50 mm published | green |
| All 5 consistency checks passed | ||||||||||||
| 51 | 530 mm published | 397 mm published | 71.0 ° derived | 73.0 ° derived | 559 mm derived | 420 mm derived | 1017 mm published | 610 mm published | 80 mm derived | 68.0 mm published | 50 mm published | green |
| All 5 consistency checks passed | ||||||||||||
| 54 | 550 mm published | 401 mm published | 72.0 ° derived | 73.0 ° derived | 569 mm derived | 420 mm derived | 1015 mm published | 608 mm published | 80 mm derived | 68.0 mm published | 45 mm published | green |
| All 5 consistency checks passed | ||||||||||||
| 56 | 570 mm published | 405 mm published | 72.0 ° derived | 73.0 ° derived | 579 mm derived | 420 mm derived | 1026 mm published | 619 mm published | 80 mm derived | 68.0 mm published | 45 mm published | yellow |
| 2 of 5 checks flagged — Wheelbase Reconciliation shows 2.4mm discrepancy | ||||||||||||
| 58 | 595 mm published | 410 mm published | 72.0 ° derived | 73.0 ° derived | 592 mm derived | 420 mm derived | 1039 mm published | 632 mm published | 80 mm derived | 68.0 mm published | 45 mm published | yellow |
| 1 of 5 checks flagged — Front Center Reconciliation shows 2.1mm discrepancy | ||||||||||||
| 61 | 620 mm published | 414 mm published | 72.0 ° derived | 73.0 ° derived | 604 mm derived | 420 mm derived | 1051 mm published | 644 mm published | 80 mm derived | 68.0 mm published | 45 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.
The BMC Kaius geometry reconciles well with the RideDNA forward model across all six sizes. Stack and reach show excellent agreement within ±1mm engineering tolerance across the entire size run. Wheelbase shows a 2.4mm data inaccuracy on size 56; front center shows 2.5mm and 2.1mm data inaccuracies on sizes 56 and 58 respectively. Trail reconciles within ±1mm engineering tolerance across all sizes.