2021 Decathlon RockRider ST 900 S
- Category
- Full-suspension Trail MTB
- Design
- Flat Bar, Full suspension
- Frame
- Aluminum
- Fork
- Steel
- Suspension
- 120mm fork travel, 120mm rear travel
- Features
- Disc brake
Average stack and reachvs category Suspension sag unknown Geometry may mis-represent actual riding geometry | Average stack and reachvs category Suspension sag unknown Geometry may mis-represent actual riding geometry | Average stack and reachvs category Suspension sag unknown Geometry may mis-represent actual riding geometry |
Geometry
M | L | XL | |
Stack | 596mm | 605mm | 619mm |
Reach | 403mm | 430mm | 446mm |
Stack to Reach Ratio | 1.48:1 | 1.41:1 | 1.39:1 |
Seat Tube Length, Unknown | 443mm | 443mm | 493mm |
Top Tube Length, Effective/Horizontal Unknown | 585mm | 615mm | 635mm |
Top Tube Slope | 17.9deg | 18deg | 14deg |
Head Tube Angle | 68.5deg | 68.5deg | 68.5deg |
Seat Tube Angle | 73deg | 73deg | 73deg |
Head Tube Length | 130mm | 140mm | 155mm |
Bottom Bracket Drop | 15mm | 15mm | 15mm |
Bottom Bracket Height | 332.9mm | 332.9mm | 332.9mm |
Chainstay Length Horizontal | 436mm | 436mm | 436mm |
Front-Center | 677.2mm | 708.2mm | 729.2mm |
Front-Center Horizontal | 677mm | 708mm | 729mm |
Wheelbase | 1113mm | 1144mm | 1165mm |
Fork Offset/Rake | 42mm | 42mm | 42mm |
Fork Length, Unknown | 508mm | 508mm | 508mm |
Trail | 91.9mm very high | 91.9mm very high | 91.9mm very high |
Mechanical Trail | 85.5mm | 85.5mm | 85.5mm |
Wheel Flop | 31.3mm | 31.3mm | 31.3mm |
Tire to Pedal Spindle | 154.3mm 175 mm cranks | 185.3mm 175 mm cranks | 206.3mm 175 mm cranks |
Pedal Spindle to Ground Clearance | 157.9mm 175 mm cranks | 157.9mm 175 mm cranks | 157.9mm 175 mm cranks |
ST 900 S Build
M | L | XL | |
Wheel Size | 650B/27.5 in 584 mm BSD | 650B/27.5 in 584 mm BSD | 650B/27.5 in 584 mm BSD |
Tire Width | 2.2in | 2.2in | 2.2in |
Tire Outer Diameter | 695.8mm | 695.8mm | 695.8mm |
Bike Length with Tires | 1808.8mm | 1839.8mm | 1860.8mm |
Crank Length | 175mm | 175mm | 175mm |
Handlebar Width | 720mm | 720mm | 720mm |
Stem Length | 80mm | 80mm | 90mm |
Published Sizing Recommendations
Height | 165 cm to 174 cm | 175 cm to 184 cm | 185 cm to 200 cm |
Stack and Reach vs. Category Trend
Very Upright
Somewhat Upright
Average
Somewhat Aggressive
Very Aggressive
The Bike Insights Upright/Aggressive scale is based on analysis of a bike’s proportions relative to similar sized bikes in the same category.
Learn more about the Upright/Aggressive ScaleCategory Trend
Full-suspension Trail MTBSource:https://www.decathlon.it/p/mtb-st-900-s-grigio-giallo-27-5/_/R-p-301099?mc=8500764&c=GRIGIO