BMC Blast 27

Name: BMC Blast 27
Brand: BMC

2021 MountainCross-country Manufacturer page

Fork travel: 100 mm
Wheels: 27.5″
Drivetrain: 1 × 10 32t / 10–46t
Gear range: 460%
Weight: 13.46 kg 29.7 lb · Reference configuration not specified
Brakes: Hydraulic disc

Rider height by size (cm)

Size guide

XS Not informed
SM 162–172
MD 170–182
LG 180–192
XL 190+

Components

12 of 17 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

Blast 27", • 1 1/8" Head Tube, • BSA Threaded Bottom Bracket, • 160mm Post Mount, • 9X135mm QR Not identified

Suspension

1 part

Fork
- SR Suntour

Drivetrain

6 parts

Bottom bracket

BSA, 73mm, threaded Not identified
Cassette
- Shimano Deore CS-M4100 10 speeds 10–46t
CS-M4100
Chain
- Shimano CN-HG54
CN-HG54
Crankset

Lightweight Forged Alloy Cranks, 32T 1x Specific Narrow Wide chainring, 170mm Not identified
Rear derailleur
- Shimano Deore
Shifters
- Shimano Deore

Brakes

1 part

Brakes
- Shimano BR-MT200
BR-MT200RT-30

Wheels and tires

4 parts

Front hub
- Shimano HB-RM35
HB-RM35FH-RM35
Rear hub
- Shimano FH-RM35
FH-RM35HB-RM35
Rims

XCD23 Not identified
Tires
- Maxxis Ardent Race

Cockpit and contact points

4 parts

Handlebar
- BMC
Saddle

Velo VL3381 Not identified
Seatpost
- BMC
Stem
- BMC

Sizes and geometry

5 sizes Open in the geometry plotter

Enter your height to highlight matching ranges.

Size MD

Table

Reach 425mm

Stack 604mm

Wheelbase 1107mm

Head angle 70.0°

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 5 published sizes

Complete manufacturer geometry by size
Measurement
Frame
Reachmm	385	405	425	445	465
Stackmm	580	594	604	622	632
Top tube lengthmm	558	586	610	635	654
Seat tube lengthmm	380	420	460	500	540
Head tube lengthmm	100	110	120	140	150
Head tube angle	70°	70°	70°	70°	70°
Seat tube angle	73°	73°	73°	73°	73°
Chainstay lengthmm	435	435	435	435	435
Wheelbasemm	1053	1083	1107	1133	1152
Front centermm	622	652	675	701	720
Bottom bracket dropmm	42	42	42	42	42
Bottom bracket heightmm	313	313	313	313	313
Standover heightmm	704	744	766	779	825
Fork rakemm	42	42	42	42	42
Trailmm	82	82	82	82	82
Stack/reach ratio	1.51	1.47	1.42	1.40	1.36
Suspension and parts
Crank lengthmm	170	170	175	175	175
Handlebar widthmm	700	700	700	700	700
Stem lengthmm	70	70	70	70	90
Stem angle	7°	7°	7°	7°	7°
Seatpost lengthmm	350	350	350	400	400

Not published by the manufacturer: Front travel, Rear travel and Dropper post travel.

Specifications

Frame and fork

Intended fit: Unisex
Bicycle weight: 13.46 kg

29.7 lb
Weight limit: 110 kg

242.5 lb

Suspension

Suspension configuration: Hardtail
Front travel: 100 mm

Drivetrain

Derived by Bikelake

Front chainrings: 1
Smallest chainring: 32
Largest chainring: 32
Rear sprockets: 10
Smallest sprocket: 10
Largest sprocket: 46
Lowest gear: 19.1 in
Highest gear: 88.0 in

Wheels and brakes

Wheel configuration: Same size
Brake type: Hydraulic disc

Fit and controls

Seatpost: Rigid seatpost
Shifting: Mechanical

Additional specifications

Bottom bracket standard: BSA
Fork spring: Coil
Tire width: 2.2″
Wheel material: Aluminum
Wheel size: 27.5″

Technical analysis

4 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: 2021
Sample: 1,256 bicycles with this information
Coverage: 91.6% of the class

Lowest gear

19.1 gear inches

This value is within the central range for this class.

Cohort: Mountain / Cross-country Model year: 2021
Sample: 1,101 bicycles with this information
Coverage: 80.3% of the class

Highest gear

88.0 gear inches

This value is below the central range for this class.

Cohort: Mountain / Cross-country Model year: 2021
Sample: 1,101 bicycles with this information
Coverage: 80.3% of the class

Shifting

Mechanical

89 of 1,368 bicycles with this information use electronic shifting.

Cohort: Mountain / Cross-country Model year: 2021
Sample: 1,368 bicycles with this information
Coverage: 99.7% of the class

Gearing

Estimated speeds at 80 rpm

Lowest gear: 7.3 km/h
Highest gear: 33.7 km/h

Total gear range 460%

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: 19.1–88.0 gear inches
Class reference (p10–p90): 17.4–100.2 gear inches; The band runs from p10 for the lowest gear to p90 for the highest gear.

Cohort: Mountain / Cross-country Model year: 2021
Lowest gear: 1101 bicycles with this information, 80.3% of the class
Highest gear: 1101 bicycles with this information, 80.3% 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 2021 builds
Specification	This bicycle BMC Blast 27	BMC Blast 20
Frame
Bicycle weight	13.46 kg	9.18 kg
Weight limit	110 kg	Not informed
Frame material	Not informed	Aluminum
Fork material	Not informed	Aluminum
Suspension
Suspension configuration	Hardtail	Rigid
Front travel	100 mm	Not informed
Drivetrain
Rear sprockets	10	8
Smallest sprocket	10	11
Largest sprocket	46	34
Lowest gear	19.1 in	18.8 in
Highest gear	88.0 in	58.2 in
Other specifications
Fork spring	Coil	Not informed
Suspension	Hardtail	Rigid
Tire width	2.2″	2.4″
Wheel size	27.5″	20″