2026 Curtis Slackjack Base
- Category
- Progressive Gravel
- Design
- Drop Bar, Rigid, non-suspension corrected
- Frame
- Steel
- Features
- Disc brake
Geometry
XS | S | M | L | XL | XXL | |
Stack | 553mm | 562mm | 571mm | 580mm | 589mm | 599mm |
Reach | 380mm | 390mm | 395mm | 405mm | 410mm | 420mm |
Stack to Reach Ratio | 1.46:1 | 1.44:1 | 1.45:1 | 1.43:1 | 1.44:1 | 1.43:1 |
Seat Tube Length, C-T | 450mm | 470mm | 490mm | 510mm | 530mm | 560mm |
Top Tube Slope | 13.4deg | 12deg | 10.7deg | 9.3deg | 8.1deg | 6deg |
Head Tube Angle | 68deg | 68deg | 68deg | 68deg | 68deg | 68deg |
Seat Tube Angle | 74deg | 74deg | 74deg | 74deg | 74deg | 74deg |
Head Tube Length | 110mm | 120mm | 130mm | 140mm | 150mm | 160mm |
Bottom Bracket Drop | 70mm | 70mm | 70mm | 70mm | 70mm | 70mm |
Bottom Bracket Height | 291mm | 291mm | 291mm | 291mm | 291mm | 291mm |
Chainstay Length | 435mm | 435mm | 435mm | 435mm | 435mm | 435mm |
Chainstay Length Horizontal | 429.3mm | 429.3mm | 429.3mm | 429.3mm | 429.3mm | 429.3mm |
Front-Center | 627.6mm | 641.2mm | 649.7mm | 663.3mm | 671.9mm | 685.9mm |
Front-Center Horizontal | 623.7mm | 637.3mm | 646mm | 659.6mm | 668.2mm | 682.3mm |
Wheelbase | 1053mm | 1066.7mm | 1075.3mm | 1088.9mm | 1097.6mm | 1111.6mm |
Fork Offset/Rake | 45mm | 45mm | 45mm | 45mm | 45mm | 45mm |
Trail | 97.3mm very high | 97.3mm very high | 97.3mm very high | 97.3mm very high | 97.3mm very high | 97.3mm very high |
Mechanical Trail | 90.2mm | 90.2mm | 90.2mm | 90.2mm | 90.2mm | 90.2mm |
Wheel Flop | 33.8mm | 33.8mm | 33.8mm | 33.8mm | 33.8mm | 33.8mm |
Tire to Pedal Spindle | 96.6mm 170 mm cranks | 110.2mm 170 mm cranks | 118.7mm 170 mm cranks | 132.3mm 170 mm cranks | 140.9mm 170 mm cranks | 154.9mm 170 mm cranks |
Pedal Spindle to Ground Clearance | 121mm 170 mm cranks | 121mm 170 mm cranks | 121mm 170 mm cranks | 121mm 170 mm cranks | 121mm 170 mm cranks | 121mm 170 mm cranks |
Base Build
XS | S | M | L | XL | XXL | |
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 | 50mm | 50mm | 50mm | 50mm | 50mm | 50mm |
Tire Outer Diameter | 722mm | 722mm | 722mm | 722mm | 722mm | 722mm |
Bike Length with Tires | 1775mm | 1788.7mm | 1797.3mm | 1810.9mm | 1819.6mm | 1833.6mm |
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
Progressive GravelSource:curtisbikes.co.uk