Jamis Helix A1

Name: Jamis Helix A1
Brand: Jamis

2020 MountainCross-country Manufacturer page

Last known price: $599

Prices shown first for United States
Fork travel: 100 mm
Wheels: 27.5″
Drivetrain: 3 × 8 24–42t / 12–32t
Gear range: 467%
Weight: 14.17 kg 31.2 lb · Reference configuration not specified
Frame: Aluminum
Brakes: Hydraulic disc

Sizes

Size guide

The manufacturer did not publish rider heights for these sizes.

Components

14 of 19 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

6061 aluminum main tubes, over-sized seat tube, zero-stack head tube, over-sized stays, replaceable derailleur hanger Not identified

Suspension

1 part

Fork
- SR Suntour XCT30

Drivetrain

7 parts

Bottom bracket

Sealed cartridge Not identified
Cassette
- Shimano CS-HG200 12–32t
CS-HG200
Chain
- KMC Z7 7 speeds
Crankset
- Shimano FC-TY301 8 speeds 42/34/24t
FC-TY301TY-301
Front derailleur
- Shimano Tourney FD-TY700
FD-TY700
Rear derailleur
- Shimano Tourney TX RD-TX800 8 speeds
RD-TX800
Shifters
- Shimano Altus SL-M310
SL-M310

Brakes

1 part

Brakes
- Tektro HD-M275 / HD-M276
HD-M275HD-M276

Wheels and tires

2 parts

Cockpit and contact points

7 parts

Grips

Kraton Not identified
Handlebar
- Jamis
Headset

Zero-stack internal cup threadless, 15mm cone spacer Not identified
Pedals

MTB platform, hi-impact resin Not identified
Saddle
- Jamis
Seatpost
- Jamis
Stem
- Jamis

Sizes and geometry

3 sizes Open in the geometry plotter

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

Size 16"

Table

Geometry diagram unavailable

The drawing needs reach and stack, which the manufacturer did not publish. Available facts remain in the table.

Size

Complete manufacturer geometry table 3 published sizes

Complete manufacturer geometry by size
Measurement
Top tube lengthmm	540	560	580
Seat tube lengthmm	356	406	457
Head tube lengthmm	105	110	120
Head tube angle	70°	70°	70°
Seat tube angle	72.5°	72.5°	72.5°
Chainstay lengthmm	435	435	435
Wheelbasemm	1029	1050	1070
Front centermm	598	619	639
Bottom bracket dropmm	46	46	46
Bottom bracket heightmm	309	309	309
Standover heightmm	668	704	731

Not published by the manufacturer: Reach, Stack, Fork rake, Trail, Stack/reach ratio, 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
Fork material: Aluminum
Bicycle weight: 14.17 kg

31.2 lb

Suspension

Suspension configuration: Hardtail
Front travel: 100 mm

Drivetrain

Derived by Bikelake

Front chainrings: 3
Smallest chainring: 24
Largest chainring: 42
Rear sprockets: 8
Smallest sprocket: 12
Largest sprocket: 32
Lowest gear: 20.6 in
Highest gear: 96.3 in

Wheels and brakes

Wheel configuration: Same size
Brake type: Hydraulic disc

Fit and controls

Seatpost: Rigid seatpost
Shifting: Mechanical

Additional specifications

Fork spring: Coil
Tire width: 2.25″
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: 2020
Sample: 1,088 bicycles with this information
Coverage: 86.0% of the class

Lowest gear

20.6 gear inches

This value is above the central range for this class.

Cohort: Mountain / Cross-country Model year: 2020
Sample: 1,057 bicycles with this information
Coverage: 83.6% of the class

Highest gear

96.3 gear inches

This value is within the central range for this class.

Cohort: Mountain / Cross-country Model year: 2020
Sample: 1,057 bicycles with this information
Coverage: 83.6% of the class

Shifting

Mechanical

57 of 1,264 bicycles with this information use electronic shifting.

Cohort: Mountain / Cross-country Model year: 2020
Sample: 1,264 bicycles with this information
Coverage: 100.0% of the class

Gearing

Estimated speeds at 80 rpm

Lowest gear: 7.9 km/h
Highest gear: 36.9 km/h

Total gear range 467%

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: 20.6–96.3 gear inches
Class reference (p10–p90): 17.4–105.0 gear inches; The band runs from p10 for the lowest gear to p90 for the highest gear.

Cohort: Mountain / Cross-country Model year: 2020
Lowest gear: 1057 bicycles with this information, 83.6% of the class
Highest gear: 1057 bicycles with this information, 83.6% 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 2020 builds
Specification	This bicycle Jamis Helix A1	Jamis Helix A2
Frame
Bicycle weight	14.17 kg	14.51 kg
Drivetrain
Rear sprockets	8	7
Smallest sprocket	12	14
Largest sprocket	32	34
Lowest gear	20.6 in	19.4 in
Highest gear	96.3 in	82.5 in
Brakes
Brake type	Hydraulic disc	Mechanical disc