Author Traction 27.5

2019 MountainCross-country Manufacturer page

Fork travel: 100 mm
Wheels: 27.5″
Drivetrain: 2 × 10 24–38t / 11–42t
Gear range: 605%
Weight: 12.7 kg 28.0 lb · Reference configuration not specified
Frame: Aluminum
Brakes: Hydraulic disc

Rider height by size (cm)

Size guide

15" 145–158
17" 155–172
19" 170–185
21" 182–200

Components

18 of 20 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

double butted hydroformed alloy 6061 27.5" Not identified

Suspension

1 part

Fork
- RST

Drivetrain

6 parts

Cassette
- Shimano CS-HG500-10 10 speeds
CS-HG500-10
Chain
- KMC X10 10 speeds
Crankset
- Shimano
Front derailleur
- Shimano Deore
Rear derailleur
- Shimano Deore
Shifters
- Shimano Deore

Brakes

1 part

Brakes
- Tektro Gemini

Wheels and tires

5 parts

Front hub
- Author
Rear hub
- Author
Rims
- Author
Spokes

black stainless steel 2.0 mm Not identified
Tires
- Vittoria

Cockpit and contact points

6 parts

Sizes and geometry

4 sizes Open in the geometry plotter

Enter your height to highlight matching ranges.

Size 17"

Table

Reach 379mm

Stack 599mm

Wheelbase 1076mm

Head angle 69.0°

Seat angle 73.0°

Every size is drawn to the same scale, in millimeters. Explanatory schematic on an assumed 27.5″ 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
Reachmm	362	379	402	419
Stackmm	590	599	604	613
Top tube lengthmm	570	590	615	635
Seat tube lengthmm	381	432	483	533
Head tube lengthmm	115	125	130	140
Head tube angle	69°	69°	69°	69°
Seat tube angle	73°	73°	73°	73°
Chainstay lengthmm	435	435	435	435
Wheelbasemm	1056	1076	1101	1121
Front centermm	623	643	668	688
Bottom bracket dropmm	35	35	35	35
Bottom bracket heightmm	320	320	320	320
Fork rakemm	44	44	44	44
Trailmm	89	89	89	90
Stack/reach ratio	1.63	1.58	1.50	1.46

Not published by the manufacturer: Standover height, 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: Aluminum
Bicycle weight: 12.7 kg

28.0 lb

Suspension

Suspension configuration: Hardtail
Front travel: 100 mm

Drivetrain

Derived by Bikelake

Front chainrings: 2
Smallest chainring: 24
Largest chainring: 38
Rear sprockets: 10
Smallest sprocket: 11
Largest sprocket: 42
Lowest gear: 15.7 in
Highest gear: 95.0 in

Wheels and brakes

Wheel configuration: Same size
Brake type: Hydraulic disc

Fit and controls

Seatpost: Rigid seatpost
Shifting: Mechanical

Additional specifications

Fork spring: Air
Tire width: 2.25″
Wheel material: Aluminum
Wheel size: 27.5″

Technical analysis

3 measures

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

Front travel

100 mm

This value is within the central range for this class.

Cohort: Mountain / Cross-country Model year: 2019
Sample: 850 bicycles with this information
Coverage: 96.0% of the class

Lowest gear

15.7 gear inches

This value is below the central range for this class.

Cohort: Mountain / Cross-country Model year: 2019
Sample: 799 bicycles with this information
Coverage: 90.2% of the class

Highest gear

95.0 gear inches

This value is within the central range for this class.

Cohort: Mountain / Cross-country Model year: 2019
Sample: 799 bicycles with this information
Coverage: 90.2% of the class

Gearing

Estimated speeds at 80 rpm

Lowest gear: 6.0 km/h
Highest gear: 36.4 km/h

Total gear range 605%

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: 15.7–95.0 gear inches
Class reference (p10–p90): 16.8–105.0 gear inches; The band runs from p10 for the lowest gear to p90 for the highest gear.

Cohort: Mountain / Cross-country Model year: 2019
Lowest gear: 799 bicycles with this information, 90.2% of the class
Highest gear: 799 bicycles with this information, 90.2% 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 2019 builds

Differences across 2019 builds
Specification	This bicycle Author Traction 27.5	Author Traction 29	Author Traction 29 ASL	Author Traction ASL 27.5
Frame
Bicycle weight	12.7 kg	13.2 kg	12.9 kg	12.8 kg
Drivetrain
Lowest gear	15.7 in	16.6 in	16.6 in	15.7 in
Highest gear	95.0 in	100.2 in	100.2 in	95.0 in
Other specifications
Wheel size	27.5″	29″	29″	27.5″