2026 REI Coop ADV 2.1 Base XS
Build
700C/29 in × 45 mm
Insights
Average stack and reach vs trend of all-road/gravel bikes
Design deviates from other sizes of REI Coop ADV 2.1
Stack and Reach vs. Category Trend
View all sizes
Geometry
| Stack | 542mm |
| Reach | 365mm |
| Stack to Reach Ratio | 1.48:1 |
| Seat Tube Length, C-T | 385mm |
| Top Tube Length, Effective/Horizontal Center | 520.4mm |
| Top Tube Slope | 20.1deg |
| Head Tube Angle | 69.8deg |
| Seat Tube Angle | 74deg |
| Head Tube Length | 100mm |
| Chainstay Length | 438mm |
| Wheelbase | 1023mm |
| Fork Offset/Rake | 51mm |
| Trail | 76.6mm high |
| Mechanical Trail | 71.9mm |
| Wheel Flop | 24.8mm |
| Standover Height | 689.5mm |
| Tire to Pedal Spindle Distance With 170 mm cranks | — |
| Pedal Spindle to Ground Clearance With 170 mm cranks | — |
Base Build
| Wheel Size | 700C, 29 inch (622mm BSD) |
| Tire Width | 45mm |
| Tire Outer Diameter | 712mm |
| Bike Length with Tires | 1735mm |
| Suspension Type | Rigid, non-suspension corrected |
| Bar Type | Drop Bar |
| Frame Material | Aluminum |
| Fork Material | Carbon/Composite |
| Brake Type | Disc |
Source:https://www.rei.com/product/254161/co-op-cycles-adv-21-bike