Jamis Explorer A1

2025 MountainCross-country Manufacturer page

Last known price: $729

Prices shown first for United States
Fork travel: 80 mm
Wheels: 27.5″
Drivetrain: 3 × 8 28–48t / 12–32t
Gear range: 457%
Weight: 15.65 kg 34.5 lb · Reference configuration not specified
Frame: Aluminum
Brakes: Mechanical disc

Sizes

Size guide

The manufacturer did not publish rider heights for these sizes.

Components

10 of 18 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 TIG-welded aluminum, all-new sport comfort design with upright ride position, replaceable derailleur hanger Not identified

Suspension

1 part

Fork
- SR Suntour

Drivetrain

6 parts

Bottom bracket

Sealed cartridge, 68 x 110.5mm Not identified
Cassette
- Shimano CS-HG20
CS-HG20
Chain
- KMC Z7 7 speeds
Crankset
- Shimano FC-TY301 8 speeds 48/38/28t
FC-TY301
Rear derailleur
- Shimano Tourney TX RD-TX800 8 speeds
RD-TX800TX-800
Shifters
- Shimano ST-EF510
ST-EF510

Brakes

1 part

Brakes
- Tektro

Wheels and tires

2 parts

Rims

Double-wall alloy rims, 32H, alloy hubs with QR, 14g stainless steel spokes Not identified
Tires
- CST

Cockpit and contact points

7 parts

Grips

Kraton comfort Not identified
Handlebar

Comfort hi-rise, alloy 25.4 x 80mm rise x 15 ̊ sweep x 640mm Not identified
Headset

Internal cup, threaded, 1 1/8” Not identified
Pedals

Comfort platform with TPE non-slip insert Not identified
Saddle
- Jamis
Seatpost

Suspension, alloy micro-adjust, 350mm x 27.2mm, with alloy QR clamp Not identified
Stem
- Jamis

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 17"

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 7 published sizes

Complete manufacturer geometry by size
Measurement
Top tube lengthmm	555	565	577	587	594	598	617
Seat tube lengthmm	356	381	406	432	457	483	533
Head tube lengthmm	140	135	150	165	160	185	210
Head tube angle	69°	69°	69°	70°	70°	70°	70°
Seat tube angle	72°	71°	71°	71°	71°	71°	71°
Chainstay lengthmm	450	450	450	450	450	450	450
Wheelbasemm	1057	1055	1067	1066	1072	1077	1097
Front centermm	617	615	627	626	632	637	656
Bottom bracket dropmm	71	71	71	71	71	71	71
Bottom bracket heightmm	284	284	284	284	284	284	284
Standover heightmm	481	718	487	784	484	824	870
Fork rakemm	42	42	42	42	42	42	42

Not published by the manufacturer: Reach, Stack, 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: 15.65 kg

34.5 lb

Suspension

Suspension configuration: Hardtail
Front travel: 80 mm

Drivetrain

Derived by Bikelake

Front chainrings: 3
Smallest chainring: 28
Largest chainring: 48
Rear sprockets: 8
Smallest sprocket: 12
Largest sprocket: 32
Lowest gear: 24.1 in
Highest gear: 110.0 in

Wheels and brakes

Wheel configuration: Same size
Brake type: Mechanical disc

Fit and controls

Seatpost: suspension
Shifting: Mechanical

Additional specifications

Fork spring: Coil
Tire width: 2.1″
Wheel material: Aluminum
Wheel size: 27.5″

Technical analysis

2 measures

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

Front travel

80 mm

This value is below the central range for this class.

Cohort: Mountain / Cross-country Model year: 2025
Sample: 1,508 bicycles with this information
Coverage: 87.8% of the class

Shifting

Mechanical

222 of 1,648 bicycles with this information use electronic shifting.

Cohort: Mountain / Cross-country Model year: 2025
Sample: 1,648 bicycles with this information
Coverage: 95.9% of the class

Gearing

Estimated speeds at 80 rpm

Lowest gear: 9.2 km/h
Highest gear: 42.1 km/h

Total gear range 457%

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: 24.1–110.0 gear inches

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 2025 builds
Specification	This bicycle Jamis Explorer A1	Jamis Explorer A2
Frame
Fork material	Aluminum	Steel
Bicycle weight	15.65 kg	13.83 kg
Suspension
Suspension configuration	Hardtail	Rigid
Front travel	80 mm	Not informed
Drivetrain
Rear sprockets	8	7
Smallest sprocket	12	14
Largest sprocket	32	34
Lowest gear	24.1 in	22.7 in
Highest gear	110.0 in	94.3 in
Brakes
Brake type	Mechanical disc	Rim brake
Cockpit
Seatpost	suspension	Rigid seatpost
Other specifications
Fork spring	Coil	Not informed
Suspension	Hardtail	Rigid
Wheel size	27.5″	650b