2025 Trek Bikes Session 8
- Design
- Moto/Klunker/Riser Bar, Full suspension
- Frame
- Aluminum
- Suspension
- 200mm fork travel, 200mm rear travel, 20% sag
- Features
- Disc brake
Geometry
R1(L) | R1(H) | R2(L) | R2(H) | R3(L) | R3(H) | |
Stack | 639mm | 634mm | 639mm | 634mm | 639mm | 634mm |
Reach | 440mm | 447mm | 465mm | 472mm | 493mm | 499mm |
Stack to Reach Ratio | 1.45:1 | 1.42:1 | 1.37:1 | 1.34:1 | 1.3:1 | 1.27:1 |
Seat Tube Length, C-T | 425mm | 425mm | 425mm | 425mm | 425mm | 425mm |
Top Tube Length, Effective/Horizontal HT Top | 587mm | 586mm | 618mm | 617mm | 653mm | 652mm |
Head Tube Angle | 63deg | 63.6deg | 63deg | 63.6deg | 63deg | 63.6deg |
Effective Seat Tube Angle, ETT HT Top | 76.5deg | 77.1deg | 76.5deg | 77.1deg | 76.5deg | 77.1deg |
Head Tube Length | 117mm | 117mm | 117mm | 117mm | 117mm | 117mm |
Bottom Bracket Drop | 21mm | 12mm | 21mm | 12mm | 21mm | 12mm |
Bottom Bracket Height | 353.5mm | 362.5mm | 353.5mm | 362.5mm | 353.5mm | 362.5mm |
Chainstay Length | 439mm | 435mm | 445mm | 441mm | 452mm | 448mm |
Chainstay Length Horizontal | 438.5mm | 434.8mm | 444.5mm | 440.8mm | 451.5mm | 447.8mm |
Front-Center | 807.8mm | 808.3mm | 832.8mm | 833.3mm | 860.7mm | 861.2mm |
Front-Center Horizontal | 807.5mm | 808.2mm | 832.5mm | 833.2mm | 860.5mm | 861.2mm |
Wheelbase | 1246mm | 1243mm | 1277mm | 1274mm | 1312mm | 1309mm |
Fork Offset/Rake | 46mm | 46mm | 46mm | 46mm | 46mm | 46mm |
Trail | 139.2mm very high | 134.6mm very high | 139.2mm very high | 134.6mm very high | 139.2mm very high | 134.6mm very high |
Mechanical Trail | 124mm | 120.5mm | 124mm | 120.5mm | 124mm | 120.5mm |
Wheel Flop | 56.3mm | 53.6mm | 56.3mm | 53.6mm | 56.3mm | 53.6mm |
Standover Height | 747mm | 755mm | 751mm | 759mm | 749mm | 757mm |
Tire to Pedal Spindle | 268.3mm 165 mm cranks | 268.8mm 165 mm cranks | 293.3mm 165 mm cranks | 293.8mm 165 mm cranks | 321.2mm 165 mm cranks | 321.7mm 165 mm cranks |
Pedal Spindle to Ground Clearance | 188.5mm 165 mm cranks | 197.5mm 165 mm cranks | 188.5mm 165 mm cranks | 197.5mm 165 mm cranks | 188.5mm 165 mm cranks | 197.5mm 165 mm cranks |
8 Build
R1(L) | R1(H) | R2(L) | R2(H) | R3(L) | R3(H) | |
Wheel Size | 700C/29 in 622 mm BSD | 700C/29 in 622 mm BSD | 700C/29 in 622 mm BSD | 700C/29 in 622 mm BSD | 700C/29 in 622 mm BSD | 700C/29 in 622 mm BSD |
Tire Width | 2.5in | 2.5in | 2.5in | 2.5in | 2.5in | 2.5in |
Tire Width Max | 2.5in | 2.5in | 2.5in | 2.5in | 2.5in | 2.5in |
Tire Outer Diameter | 749mm | 749mm | 749mm | 749mm | 749mm | 749mm |
Bike Length with Tires | 1995mm | 1992mm | 2026mm | 2023mm | 2061mm | 2058mm |
Crank Length | 165mm | 165mm | 165mm | 165mm | 165mm | 165mm |
Handlebar Width | 780mm | 780mm | 780mm | 780mm | 780mm | 780mm |
Stem Length | 50mm | 50mm | 50mm | 50mm | 50mm | 50mm |
Stem Angle | 0deg | 0deg | 0deg | 0deg | 0deg | 0deg |
Published Sizing Recommendations
Height | 161 cm to 175 cm | 161 cm to 175 cm | 174 cm to 188 cm | 174 cm to 188 cm | 186 cm to 196 cm | 186 cm to 196 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 Downhill/Freeride MTBSource:https://www.trekbikes.com/us/en_US/bikes/mountain-bikes/downhill-mountain-bikes/session/session-8-29-gx/p/37056/