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Arktos 27.5 Custom


Bike Builder

Ride Now, Pay Later

Featuring Alchemy’s exclusive Sine full-suspension system

The Made in the USA Arktos 27.5 is the flagship of our mountain fleet. Every detail is is painstakingly done in house by Alchemy craftsmen, from the first layer of carbon to the last coat of paint.

Frameset Features

// Exclusive Patented Sine Suspension System

The Arktos is a one-of-a-kind, do-it-all full-suspension bike designed to climb and descend with the same aplomb. The Arktos features a patented dual-linkage platform called the Sine Suspension, which was designed by suspension guru David Earle. The Sine name is derived from the way the shock rate, when graphed, resembles a sine wave. With Sine, there is regression through the first part of the travel to absorb small bumps and provide climbing traction, progression in the middle of the stroke to avoid wallowing on big hits or in hard, fast corners, and then slight regression again at end stroke to enable full use of rear wheel travel. Sine is also designed to minimize chainstay growth to improve pedaling efficiency and keep the suspension active under braking.


// Fully Triangulated Rear Swingarm

Modern trail bikes today are being ridden on terrain that only a DH bike would have tackled a few years ago. As a result, the requirements for frame stiffness are increasing every year. Luckily if you are riding an Arktos, you are riding one of the laterally stiffest bikes ever produced, and one of the big reasons for this is the full triangulated rear swingarm. The Arktos by design is made to handle all you can throw at it.

// The Details

They say the devil is in the details, and there’s not doubt we focused on the minutia with the Arktos 27.5. The bike features details like internal cable routing and a direct mount chain guide, as well as every bike features Fox Factory suspension both front and rear. The rear shock has been specially tuned for Alchemy to provide the best in pedaling efficiency and downhill performance and all of the bikes are using stiff and light Fox 36 forks.


170mm Fork | 39mm Offset Fork
Seat Tube Length 420 455 483 518
Effective Top Tube 585 600 615 642
Head Tube Length 100 110 115 130
Head Tube Angle 65.5 65.5 65.5 65.5
Frame Stack 589 599 604 614
Frame Reach 401 415 431 448
Seat Tube Angle 73.5 73.5 73.5 73.5
Chain Stay Length 438 438 438 438
Bottom Bracket Drop 10 10 10 10
Bottom Bracket Height 346 346 346 346
Wheelbase 1161 1171 1185 1212

Pricing and specifications subject to change at any time without notice.

Frame Geometry
Height Pant Inseam (inches) Size
5 ft. 1 in. – 5 ft. 4 in. 30 Small
5 ft. 5 in. – 5 ft. 8 in. 32 Medium
5 ft. 9 in. – 5 ft. 11 in. 34 large
≥ 6 ft. 36 Xlarge
Arktos 29 Frame Sizing
S 5’1 – 5’5″
M 5’5″ – 5’9″
L 5’9″ – 6’1″
XL 6’1″ – 6’5″


Fork Fox 36 Factory Kashima 160mm Boost 15mm
Shock Fox DPX2 Factory Kashima EVOL LV 3-Position Adjust 8.5×2.5 in, 10X22 mm Hardware
Handlebar ENVE M6 780mm 7.5 Degree 31.8mm
Stem ENVE M6 55mm 31.8mm
Seat Post Fox Transfer Factory w Lever
Grips Ergon GA 20 Black
Headset Top Cane Creek 40-Series IS41 Short Cover – Top – Black
Headset Bottom Cane Creek 40-Series IS52 – Bottom – Black
Spacer Cane Creek 40-Series 5MM Spacer – Black
Saddle WTB Volt Race 142X165
Shifters Shimano XTR M9100 12 Speed
Rear Derailleur Shimano XTR M9120, XTR SGS, 12-SPEED
Cassette Shimano XTR M9100 12-Speed 11-51t
Cranks Shimano XTR FC-M9100-1 32 T 175mm
Bottom Bracket Shimano XTR Threaded
Chain Shimano XTR 12 Speed
Brakes Shimano XTR M9120 Trail Hydraulic
Rotors Shimano XTR M900 180mm Center Lock Ice Tech Rotor
Front Wheel ENVE M630 15/110mm
Rear Wheel ENVE M630 12/157 mm TA DT 240 Boost Shimano Driver
Tires Maxxis Minion DHF 27.5×2.5 DC EXO TR, Maxxis Minion DHR 27.5×2.4 DC EXO TR

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