Basso Astra Shimano 105 Di2

Name: Basso Astra Shimano 105 Di2
Brand: Basso

2026 RoadRace Manufacturer page

Price: Not published

Prices shown first for United States
Europe: €3,699 Last known price
Suspension: Rigid
Wheels: 700c
Drivetrain: 2 × 12 34–50t / 11–34t
Gear range: 455%
Frame: Carbon
Brakes: Hydraulic disc

Sizes

Size guide

45cm
48cm
51cm
53cm
56cm
58cm
61cm

The manufacturer did not publish rider heights for these sizes.

Components

3 of 4 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.

Drivetrain

3 parts

Cassette
- Shimano 105 CS-R7101 12 speeds 11–34t
CS-R7101
Crankset
- Shimano 105 FC-R7100 12 speeds 34t
FC-R7100
Rear derailleur
- Shimano 105 RD-R7150 12 speeds
RD-R7150

Brakes

1 part

Brakes

Hydraulic Disc Not identified

Sizes and geometry

7 sizes Open in the geometry plotter

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

Size 53cm

Table

Geometry diagram unavailable

The drawing needs wheelbase and bottom bracket drop / Bottom bracket height, which the manufacturer did not publish. Available facts remain in the table.

Size Reach Stack

Complete manufacturer geometry table 7 published sizes

Complete manufacturer geometry by size
Measurement
Frame
Reachmm	371.1	371.1	374.5	380.4	382.1	384.4	385.5
Stackmm	538.9	538.9	563.4	575.9	602.4	625.4	650.4
Top tube lengthmm	505	515	525	545	560	575	590
Seat tube lengthmm	450	480	510	530	560	580	610
Head tube lengthmm	125	125	150	162	180	204	228
Head tube angle	71.8°	71.8°	72°	72.3°	73.5°	73.5°	74°
Seat tube angle	76°	75°	75°	74°	73.5°	73°	72.5°
Chainstay lengthmm	404	404	404	404	406	410	410
Stack/reach ratio	1.45	1.45	1.50	1.51	1.58	1.63	1.69
Suspension and parts
Handlebar widthmm	400	400	420	420	420	420	440
Stem lengthmm	80	90	100	110	110	120	120

Not published by the manufacturer: Wheelbase, Front center, Bottom bracket drop, Bottom bracket height, Standover height, Fork rake, Trail, Front travel, Rear travel, Crank 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: 34
Largest chainring: 50
Rear sprockets: 12
Smallest sprocket: 11
Largest sprocket: 34
Lowest gear: 29.0 in
Highest gear: 131.8 in

Wheels and brakes

Wheel configuration: Same size
Brake type: Hydraulic disc

Fit and controls

Shifting: Electronic

Additional specifications

Tire clearance: Maximum tire width: 35c
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

29.0 gear inches

This value is within the central range for this class.

Cohort: Road / Race Model year: 2026
Sample: 719 bicycles with this information
Coverage: 78.6% of the class

Highest gear

131.8 gear inches

This value is within the central range for this class.

Cohort: Road / Race Model year: 2026
Sample: 719 bicycles with this information
Coverage: 78.6% of the class

Shifting

Electronic

631 of 912 bicycles with this information use electronic shifting.

Cohort: Road / Race Model year: 2026
Sample: 912 bicycles with this information
Coverage: 99.7% of the class

Gearing

Estimated speeds at 80 rpm

Lowest gear: 11.1 km/h
Highest gear: 50.5 km/h

Total gear range 455%

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: 29.0–131.8 gear inches
Class reference (p10–p90): 27.4–139.2 gear inches; The band runs from p10 for the lowest gear to p90 for the highest gear.

Cohort: Road / Race Model year: 2026
Lowest gear: 719 bicycles with this information, 78.6% of the class
Highest gear: 719 bicycles with this information, 78.6% 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 2026 builds
Specification	This bicycle Basso Astra Shimano 105 Di2	Basso Astra Shimano Ultegra 8170 Di2
Drivetrain
Rear sprockets	12	Not informed
Brakes
Brake type	Hydraulic disc	Rim brake
Cockpit
Seatpost	Not informed	Rigid seatpost
Other specifications
Tire width	Not informed	28c
Wheel material	Not informed	Aluminum