2026 Principia Gravel 40 Base 54cm
Build
700C/29 in × 45 mm
Insights
Average stack and reach vs trend of all-road/gravel bikes
Design deviates from other sizes of Principia Gravel 40
Stack and Reach vs. Category Trend
View all sizes
Geometry
| Stack | 579mm |
| Reach | 389mm |
| Stack to Reach Ratio | 1.49:1 |
| Seat Tube Length, Unknown | 540mm |
| Top Tube Length, Effective/Horizontal Center | 555mm |
| Top Tube Slope | 6.4deg |
| Head Tube Angle | 71.5deg |
| Seat Tube Angle | 74deg |
| Head Tube Length | 155mm |
| Bottom Bracket Drop | 67mm |
| Bottom Bracket Height | 289mm |
| Chainstay Length | 435mm |
| Chainstay Length Horizontal | 429.8mm |
| Front-Center | 611.4mm |
| Front-Center Horizontal | 607.8mm |
| Wheelbase | 1037.6mm |
| Fork Offset/Rake | 45mm |
| Fork Length, Unknown | 400mm |
| Trail | 71.7mm high |
| Mechanical Trail | 68mm |
| Wheel Flop | 21.6mm |
| Tire to Pedal Spindle Distance With 170 mm cranks | 85.4mm |
| Pedal Spindle to Ground Clearance With 170 mm cranks | 119mm |
Base Build
| Wheel Size | 700C, 29 inch (622mm BSD) |
| Tire Width | 45mm |
| Tire Outer Diameter | 712mm |
| Bike Length with Tires | 1749.6mm |
| Crank Length | 170mm |
| Handlebar Width | 440mm |
| Stem Length | 100mm |
| Stem Angle | -7deg |
| Suspension Type | Rigid, non-suspension corrected |
| Bar Type | Drop Bar |
| Frame Material | Aluminum |
| Fork Material | Carbon/Composite |
| Brake Type | Disc |
Source:https://principiabikes.com/gravel/gravel-aluminium/gravel-40---bronze-pg-2588