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Borealis Flume NX 15" Crimson Gold Fat Bike

Borealis Flume NX 15" Crimson Gold Fat Bike
Color: Crimson Gold
Size: Small - Rigid Post
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This item can only be shipped by ground.


12 Months Free Financing

With premium frame quality and only the best components, the Borealis Flume offers the best value on the market. This expedition-ready fatty mirrors the Crestone geometry, but does so in lightweight, 6000-series aluminum. Up mountains, down glaciers, and across deserts - the Flume is ready for action. There are all kinds of alloy fat bikes on the market, but none with the Flume’s purebred heritage and durability.


Standard features include: SRAM Eagle NX 12-Speed drivetrain, SRAM Level T brakes, rigid carbon fork, carbon handlebars, carbon seat post, durable Sun Ringle Mulefüt rims and your choice of tires.
Frame geometry provides responsive handling, offering maximum control for varying conditions in snow or sand.
Tire clearance up to 26x5” and 27.5x4.5”.
Compatibility for 100-120mm of suspension travel for increased comfort and control.
Lightweight, 6000-series aluminum frame comes with 2-3 bottle cage mounts, rear rack mounts on seat stays and Lizard Skin protectors on both the down tube and drive-side chain stay.

Rockshox Bluto Fork tire size limitations: 26x5” or 27.5x4”
Mastodon Pro EXT Fork tire size limitations: 26x5” or 27.5x4.5”
Borealis Rigid Carbon Fork tire size limitations: 26x5” or 27.5x4.5”
Dually 29x45 and 27.5x45 Rims – Max tire width: 3”
All rims 65mm to 85mm wide are compatible with tire widths of 3.8” to 5”
HED Carbon 100mm Rims – Max tire width of 4.8”


Frame 6061 Aircraft Alloy, 197mm Rear Spacing, Internal Dropper Compatible
Fork RockShox Bluto RL 100mm, 150mm x 15mm Thru Axle Spacing
Headset FSA 1 1/8 x 1 1/2"
Rear Shock N/A
Axles Front: 15x150mm
Rear: 12x197mm
Rims/Wheels Velocity Dually 27.5 + Double-wall alloy, 39mm internal width/45mm external width
Hubs Borealis Brand 150 x 15mm, 197 x 12mm with Shimano HG Freehub Body
Spokes Stainless, 14g
Tires Schwalbe Nobby Nic 27.5 x 3.0", Tubeless Ready
Crankset SRAM DUB NX Eagle, 175mm
Chainrings 30 Tooth SRAM Direct Mount
Bottom Bracket SRAM DUB
Chain KMC 12-Speed With Quick Link
Front Derailleur N/A
Rear Derailleur SRAM NX Eagle 12-Speed
Cassette/Rear Cogs SRAM NX Eagle PG-1230 Eagle, 11-50t For HG Freehub
Shifters SRAM NX Eagle, trigger, 12-speed
Handlebars Borealis Carbon SL Low-Rise
Tape/Grips Borealis Ergonomic Locking
Stem Borealis, Length May Vary
Brake Levers SRAM Level T Hydraulic
Brakes SRAM Level T Hydraulic With 160mm 6-Bolt Rotors F/R
Pedals Basic Plastic Test Pedals
Saddle Borealis With Cut-Out
Seat Post Borealis Carbon Rigid, 31.6mm, Length May Vary
Accessories & Extras Rubberized Chainstay Protector

* Subject to change without notice.