Bicycle Archive · Specification report

2021 Jamis Explorer A1

Velopedia Archive ID 900001707

Overview

Model year	2021
Brand	Jamis
Model	EXPLORER A1
Bicycle type	Mountain
Archive ID	900001707
Original MSRP	$729.95
Colors	M: Palladium, Riptide S/T: Palladium or Teal
Sizes	15″; 17″; 19″; 21″; 14″ S/T; 16″ S/T; 18″ S/T
Weight	34.50 lbs

Frameset

Frame construction	6061 TIG-welded aluminum, all-new sport comfort design with upright ride position, replaceable derailleur hanger
Frame material	Aluminum
Fork	SR Suntour XCE 27.5”, coil spring, external preload adjustor, 28mm stanchions, aluminum lowers, 80mm travel
Fork material	Aluminum

Drivetrain

Component group	Shimano TX-800 rear, Shimano TY710 31.8mm top swing/ dual pull front
Shifters	Shimano EZ-Fire Plus, ST-EF510, 24-speed
Front derailleur	Shimano TX-800 rear, Shimano TY710 31.8mm top swing/ dual pull front
Rear derailleur	Shimano TX-800 rear, Shimano TY710 31.8mm top swing/ dual pull front
Crankset	Shimano TY301, 48/38/28T, 170mm with chainguard
Bottom bracket	Sealed cartridge, 68 x 110.5mm
Cassette	Shimano HG20, 8-speed, 12-32
Chain	KMC Z7
Pedals	Comfort platform with TPE non-slip insert

Brakes

Brakes	Tektro forged alloy direct pull brakes with Shimano levers

Cockpit & contact points

Headset	Internal cup, threaded, 1 1/8”
Handlebar	Comfort hi-rise, alloy 25.4 x 80mm rise x 15 ̊ sweep x 640mm
Stem	Jamis alloy, angle-adjustable, 90mm ext x 150mm quill (14 ̊18”) or 110mm ext x 180mm quill (19 ̊21”)
Saddle	Jamis Comfort with memory foam, synthetic suede top, burnished side panels and bumper springs
Seatpost	Suspension, alloy micro-adjust, 350mm x 27.2mm, with alloy QR clamp

Wheels & tires

Wheels	Double-wall alloy rims, 32H, alloy hubs with QR, 14g stainless steel spokes
Front tire	CST – 1918, 27.5 x 2.1
Rear tire	CST – 1918, 27.5 x 2.1
Wheel size	27.5

Geometry · 15″

Effective top tube	565 mm
Head tube	135 mm
Head-tube angle	69°
Seat-tube angle	71°
Chainstay / rear center	450 mm
Wheelbase	1055 mm
Bottom-bracket height	284 mm
Standover height	718 mm
Fork offset / rake	42 mm

Geometry · 17″

Effective top tube	587 mm
Head tube	165 mm
Head-tube angle	70°
Seat-tube angle	71°
Chainstay / rear center	450 mm
Wheelbase	1066 mm
Bottom-bracket height	284 mm
Standover height	784 mm
Fork offset / rake	42 mm

Geometry · 19″

Effective top tube	598 mm
Head tube	185 mm
Head-tube angle	70°
Seat-tube angle	71°
Chainstay / rear center	450 mm
Wheelbase	1077 mm
Bottom-bracket height	284 mm
Standover height	824 mm
Fork offset / rake	42 mm

Geometry · 21″

Effective top tube	617 mm
Head tube	210 mm
Head-tube angle	70°
Seat-tube angle	71°
Chainstay / rear center	450 mm
Wheelbase	1097 mm
Bottom-bracket height	284 mm
Standover height	870 mm
Fork offset / rake	42 mm

Geometry · 14″ S/T

Effective top tube	555 mm
Head tube	140 mm
Head-tube angle	69°
Seat-tube angle	72°
Chainstay / rear center	450 mm
Wheelbase	1057 mm
Bottom-bracket height	284 mm
Standover height	481 mm
Fork offset / rake	42 mm

Geometry · 16″ S/T

Effective top tube	577 mm
Head tube	150 mm
Head-tube angle	69°
Seat-tube angle	71°
Chainstay / rear center	450 mm
Wheelbase	1067 mm
Bottom-bracket height	284 mm
Standover height	487 mm
Fork offset / rake	42 mm

Geometry · 18″ S/T

Effective top tube	594 mm
Head tube	160 mm
Head-tube angle	70°
Seat-tube angle	71°
Chainstay / rear center	450 mm
Wheelbase	1072 mm
Bottom-bracket height	284 mm
Standover height	484 mm
Fork offset / rake	42 mm

Manufacturer-published archive data. Confirm exact standards and dimensions before ordering parts or performing service. Generated by Velopedia on September 14, 2026.