Trek Check-OUT 2026 complete geometry

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.

Published geometry by size

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
L	652 mm published	427 mm published	69.5 ° derived	73.0 ° derived	613 mm derived	442 mm derived	1135 mm published	683 mm derived	68 mm derived	88.0 mm published	45 mm published	red
3 of 4 checks flagged — Reach Reconciliation shows 13.3mm discrepancy
M	617 mm published	407 mm published	69.0 ° derived	74.2 ° derived	589 mm derived	442 mm derived	1105 mm published	676 mm derived	70 mm derived	91.0 mm published	45 mm published	red
3 of 4 checks flagged — Reach Reconciliation shows 7.4mm discrepancy
ML	634 mm published	417 mm published	69.4 ° derived	73.7 ° derived	597 mm derived	442 mm derived	1117 mm published	675 mm derived	70 mm derived	88.0 mm published	45 mm published	red
3 of 4 checks flagged — Reach Reconciliation shows 5.3mm discrepancy
S	580 mm published	395 mm published	68.8 ° derived	74.6 ° derived	564 mm derived	442 mm derived	1081 mm published	654 mm derived	70 mm derived	92.0 mm published	45 mm published	red
3 of 4 checks flagged — Reach Reconciliation shows 9.3mm discrepancy
XL	673 mm published	435 mm published	69.4 ° derived	72.6 ° derived	628 mm derived	442 mm derived	1150 mm published	696 mm derived	68 mm derived	88.0 mm published	45 mm published	red
3 of 4 checks flagged — Reach Reconciliation shows 17.9mm discrepancy

Audit context

Overall consistency: red. 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 Trek Check-OUT geometry specification shows systematic reach discrepancies across all five sizes, ranging from 5.3mm to 17.9mm — all exceeding the ±1mm engineering tolerance and classified as data inaccuracies in the published values. Wheelbase shows significant data inaccuracies on four sizes (5.7–20.7mm) with one size within tolerance. Trail shows 2.6–3.5mm data inaccuracies across all sizes. Stack reconciles within ±1mm engineering tolerance on all sizes. The GEOMETRY INSIGHTS flag an unusually large seat tube angle step of ≥1.0° between adjacent sizes (S→L: Δ-1.6°, L→M: Δ+1.2°, ML→XL: Δ-1.1°), which may indicate a transcription anomaly — verification of the affected sizes is recommended.

Trek Check-OUT 2026 geometry

Published geometry by size

Audit context

Next steps

More Trek geometry profiles