2020 Author Aura XR4 Base

Design
Drop Bar, Rigid, non-suspension corrected
Features
Disc brake
Average stack and reachvs category
Average stack and reachvs category
Average stack and reachvs category
Average stack and reachvs category
Average stack and reachvs category

Geometry

500
520
540
560
580
Stack
548mm
568mm
586mm
606mm
627mm
Reach
378mm
382mm
386mm
395mm
397mm
Stack to Reach Ratio
1.45:1
1.49:1
1.52:1
1.53:1
1.58:1
Seat Tube Length, C-T
500mm
520mm
540mm
560mm
580mm
Seat Tube Length, C-C
460mm
480mm
500mm
520mm
540mm
Top Tube Length, Effective/Horizontal HT Top
530mm
545mm
560mm
580mm
595mm
Top Tube Length, Actual C-C
518mm
532mm
546mm
563mm
576mm
Top Tube Slope
7.4deg
7.4deg
7.2deg
7.2deg
7.4deg
Head Tube Angle
70.5deg
71deg
71deg
71.5deg
72deg
Seat Tube Angle
74.5deg
74deg
73.5deg
73deg
72.5deg
Head Tube Length
120mm
140mm
160mm
180mm
200mm
Bottom Bracket Drop
70mm
70mm
69mm
68mm
68mm
Bottom Bracket Height
276mm
276mm
277mm
278mm
278mm
Chainstay Length
425mm
425mm
425mm
425mm
425mm
Chainstay Length Horizontal
419.2mm
419.2mm
419.4mm
419.5mm
419.5mm
Front-Center
598.9mm
604.9mm
615.5mm
626.2mm
630.2mm
Front-Center Horizontal
594.8mm
600.8mm
611.6mm
622.5mm
626.5mm
Wheelbase
1014mm
1020mm
1031mm
1042mm
1046mm
Fork Offset/Rake
68mm
68mm
68mm
68mm
68mm
Fork Length (Axle-To-Crown)
400mm
400mm
400mm
400mm
400mm
Trail
50.4mm
mid/​neutral
47.2mm
mid/​neutral
47.2mm
mid/​neutral
44.1mm
low
40.9mm
low
Mechanical Trail
47.5mm
44.7mm
44.7mm
41.8mm
38.9mm
Wheel Flop
15.9mm
14.5mm
14.5mm
13.3mm
12mm
Tire to Pedal Spindle
80.9mm
172 mm cranks
86.9mm
172 mm cranks
94.5mm
175 mm cranks
105.2mm
175 mm cranks
109.2mm
175 mm cranks
Pedal Spindle to Ground Clearance
104mm
172 mm cranks
104mm
172 mm cranks
102mm
175 mm cranks
103mm
175 mm cranks
103mm
175 mm cranks

Base Build

500
520
540
560
580
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
Tire Width
35mm
35mm
35mm
35mm
35mm
Tire Outer Diameter
692mm
692mm
692mm
692mm
692mm
Bike Length with Tires
1706mm
1712mm
1723mm
1734mm
1738mm
Crank Length
172mm
172mm
175mm
175mm
175mm
Handlebar Width
420mm
440mm
440mm
460mm
460mm
Stem Length
75mm
90mm
90mm
105mm
105mm

Published Sizing Recommendations

Height

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 Scale
Category Trend
All-road/Gravel
Source:https://en.author.eu/adventure/gravel-bike/author-aura-xr4-2020-ua42930102