Principia C20

Name: Principia C20
Brand: Principia

2025 RoadGravel Manufacturer page

Price: Not published

Prices shown first for United States
Europe: €2,999 Last known price
Suspension: Rigid
Wheels: 700c
Drivetrain: 2 × 12 30–46t / 11–36t
Gear range: 502%
Frame: Carbon
Brakes: Hydraulic disc

Sizes

Size guide

50cm
52cm
54cm
56cm

The manufacturer did not publish rider heights for these sizes.

Components

10 of 15 identified

Parts found in a manufacturer catalog show their brand, model and key numbers, and the steps show how precisely they are identified: brand, series, model, or the exact product. The info button has every detail and the text the manufacturer published.

Frame and fork

1 part

Frame

Carbon Not identified

Suspension

1 part

Fork

Principia CHK11 Monocoque Full Carbon Not identified

Drivetrain

5 parts

Cassette
- Shimano CS-HG710 12 speeds 11–36t
CS-HG710
Chain
- Shimano Deore CN-M6100
CN-M6100
Crankset
- Shimano GRX FC-RX610 12 speeds 30t
FC-RX610
Front derailleur
- Shimano GRX FD-RX820 2 speeds
FD-RX820
Rear derailleur
- Shimano GRX RD-RX820 12 speeds
RD-RX820

Brakes

1 part

Brakes
- Shimano GRX BR-RX820
BR-RX820

Wheels and tires

2 parts

Rims

Gravel double butted aluminium Not identified
Tires
- Panaracer

Cockpit and contact points

5 parts

Handlebar
- FSA
Pedals

Not included Not identified
Saddle

Foming DDK-510 Not identified

DDK-510
Seatpost
- Kalloy
SP-369
Stem
- FSA NS SMR
OS-185

Sizes and geometry

4 sizes Open in the geometry plotter

Complete rider-height ranges are not published for these sizes. You can still explore the geometry below.

Size 52cm

Table

Reach 379mm

Stack 598mm

Wheelbase 1034mm

Head angle 71.3°

Seat angle 73.2°

Every size is drawn to the same scale, in millimeters. Explanatory schematic on an assumed 700c wheel; exact published values are in the table below.

Size Reach Stack

Complete manufacturer geometry table 4 published sizes

Complete manufacturer geometry by size
Measurement
Reachmm	369.6	379.4	387.6	396.5
Stackmm	581.5	597.7	609.4	628.3
Top tube lengthmm	545	560	575	590
Seat tube lengthmm	500	520	540	560
Head tube lengthmm	135	150	165	185
Head tube angle	70.75°	71.25°	71.25°	71.25°
Seat tube angle	73.2°	73.2°	72.9°	72.9°
Chainstay lengthmm	435	435	435	435
Wheelbasemm	1023.9	1034.2	1047.7	1063
Front centermm	602	613	625	640
Bottom bracket dropmm	82.5	82.5	80	80
Bottom bracket heightmm	277.5	277.5	280	280
Standover heightmm	761.4	778.8	796.5	814.6
Fork rakemm	50	50	50	50
Trailmm	72.8	69.4	69.4	69.4
Stack/reach ratio	1.57	1.58	1.57	1.59

Not published by the manufacturer: Front travel, Rear travel, Crank length, Handlebar width, Stem length, Stem angle, Seatpost length and Dropper post travel.

Specifications

Frame and fork

Intended fit: Unisex
Frame material: Carbon
Fork material: Carbon

Suspension

Suspension configuration: Rigid

Drivetrain

Derived by Bikelake

Front chainrings: 2
Smallest chainring: 30
Largest chainring: 46
Rear sprockets: 12
Smallest sprocket: 11
Largest sprocket: 36
Lowest gear: 24.2 in
Highest gear: 121.3 in

Wheels and brakes

Wheel configuration: Same size
Brake type: Hydraulic disc

Fit and controls

Seatpost: Rigid seatpost
Shifting: Mechanical

Additional specifications

Tire clearance: Maximum tire width: 50c
Wheel material: Aluminum
Wheel size: 700c

Technical analysis

3 measures

How these figures sit among bicycles of the same class and model year. Context, not a ranking.

Lowest gear

24.2 gear inches

This value is within the central range for this class.

Cohort: Road / Gravel Model year: 2025
Sample: 1,536 bicycles with this information
Coverage: 76.6% of the class

Highest gear

121.3 gear inches

This value is within the central range for this class.

Cohort: Road / Gravel Model year: 2025
Sample: 1,536 bicycles with this information
Coverage: 76.6% of the class

Shifting

Mechanical

688 of 1,999 bicycles with this information use electronic shifting.

Cohort: Road / Gravel Model year: 2025
Sample: 1,999 bicycles with this information
Coverage: 99.7% of the class

Gearing

Estimated speeds at 80 rpm

Lowest gear: 9.3 km/h
Highest gear: 46.4 km/h

Total gear range 502%

Technical details and class reference

These speeds describe the gearing at the selected cadence, not how fast you can ride.
Calculated from published gear-inch values and their wheel-size assumptions.
These gearing values describe the bicycle, not a selected frame size.
A 100% range means one ratio; 500% means the highest ratio is five times the lowest.
For e-bikes, motor assistance cutoff is not represented.

Gear-inch range

Lower gear-inch values travel less distance per pedal revolution; higher values travel farther.

This bicycle: 24.2–121.3 gear inches
Class reference (p10–p90): 22.8–126.6 gear inches; The band runs from p10 for the lowest gear to p90 for the highest gear.

Cohort: Road / Gravel Model year: 2025
Lowest gear: 1536 bicycles with this information, 76.6% of the class
Highest gear: 1536 bicycles with this information, 76.6% of the class