Author Guru 3.0

Name: Author Guru 3.0
Brand: Author

2025 RoadGravel Manufacturer page

Suspension: Rigid
Wheels: 700c
Drivetrain: 2 × 12 31–48t / 11–36t
Gear range: 507%
Weight: 9 kg 19.8 lb · Reference configuration not specified
Frame: Carbon
Brakes: Hydraulic disc

Rider height by size (cm)

Size guide

SM 160–173
MD 170–180
LG 177–187
XL 184–194

Components

17 of 18 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

AUTHOR carbon Toray T700/M40 monocoque gravel (max tyre size 700 × 47C) Not identified

Suspension

1 part

Fork
- Author

Drivetrain

6 parts

Cassette
- Shimano CS-HG710-12 12 speeds
CS-HG710-12
Chain
- KMC
Crankset
- Shimano GRX FC-RX820 12 speeds
FC-RX820
Front derailleur
- Shimano GRX FD-RX825 2 speeds
FD-RX825
Rear derailleur
- Shimano GRX RD-RX825 12 speeds
RD-RX825
Shifters
- Shimano GRX

Brakes

1 part

Brakes
- Shimano GRX

Wheels and tires

5 parts

Cockpit and contact points

4 parts

Sizes and geometry

4 sizes Open in the geometry plotter

Enter your height to highlight matching ranges.

Size MD

Table

Reach 394mm

Stack 586mm

Wheelbase 1049mm

Head angle 71.0°

Seat angle 73.5°

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 Reported by the manufacturer

Complete manufacturer geometry table 4 published sizes

Complete manufacturer geometry by size
Measurement
Frame
Reachmm	381	394	406	417
Stackmm	567	586	603	624
Top tube lengthmm	549	567	585	602
Seat tube lengthmm	480	510	540	570
Head tube lengthmm	130	150	170	190
Head tube angle	70.5°	71°	71°	71°
Seat tube angle	73.5°	73.5°	73.5°	73.5°
Chainstay lengthmm	435	435	435	435
Wheelbasemm	1035	1049	1069	1086
Front centermm	611	625	645	661
Bottom bracket dropmm	74	74	74	74
Bottom bracket heightmm	275	275	275	275
Fork rakemm	47	47	47	47
Trailmm	73	70	68	69
Stack/reach ratio	1.49	1.49	1.49	1.50
Suspension and parts
Crank lengthmm	172	172	175	175
Handlebar widthmm	420	420	440	440
Stem lengthmm	80	90	90	90

Not published by the manufacturer: Standover height, Front travel, Rear travel, Stem angle, Seatpost length and Dropper post travel.

Specifications

Frame and fork

Intended fit: Unisex
Frame material: Carbon
Fork material: Carbon
Bicycle weight: 9 kg

19.8 lb

Suspension

Suspension configuration: Rigid

Drivetrain

Derived by Bikelake

Front chainrings: 2
Smallest chainring: 31
Largest chainring: 48
Rear sprockets: 12
Smallest sprocket: 11
Largest sprocket: 36
Lowest gear: 25.0 in
Highest gear: 126.6 in

Wheels and brakes

Wheel configuration: Same size
Brake type: Hydraulic disc

Fit and controls

Seatpost: Rigid seatpost
Shifting: Electronic

Additional specifications

Tire width: 40c
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

25.0 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

126.6 gear inches

This value is above 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

Electronic

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: 9.6 km/h
Highest gear: 48.5 km/h

Total gear range 507%

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: 25.0–126.6 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

Lineup changes

The published facts that differ across this family's builds and from the same model a year earlier. Missing information never counts as zero.

Differences across 2025 builds

Differences across 2025 builds
Specification	This bicycle Author Guru 3.0	Author Guru 1.0	Author Guru 2.0
Frame
Bicycle weight	9 kg	9.9 kg	9.4 kg
Drivetrain
Front chainrings	2	2	1
Smallest chainring	31	30	42
Largest chainring	48	46	42
Rear sprockets	12	11	12
Smallest sprocket	11	11	10
Largest sprocket	36	34	51
Lowest gear	25.0 in	25.6 in	23.9 in
Highest gear	126.6 in	121.3 in	121.8 in
Cockpit
Shifting	Electronic	Mechanical	Mechanical
Other specifications
Tire width	40c	38c	40c