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Borealis Flume Aluminum Fat Tire Bicycle

Borealis Flume Aluminum Fat Tire Bicycle

Regular price $ 1,799.99 USD
Regular price Sale price $ 1,799.99 USD
Sale Sold out
Shipping calculated at checkout.
Drivetrain Kit

Low stock: 1 left


The Borealis Flume is an expedition-ready fat bike that is built to handle any adventure. With a lightweight 6000-series aluminum frame, it features a SRAM Eagle NX 12-Speed drivetrain, SRAM Level T brakes, and carbon handlebars and seat post. The durable Sun Ringle Mulefüt rims and your choice of tires provide maximum control and responsiveness, even in the toughest conditions. With clearance for tires up to 26x5” and 27.5x4.5”, and compatibility with 100-120mm of suspension travel, this fat bike is perfect for tackling mountains, glaciers, and deserts. With 2-3 bottle cage mounts, rear rack mounts, and Lizard Skin protectors, it's also equipped with all the extras you need for your next adventure.

We do offer different wheel sets and tires options on these builds. 

Contact us today to build your custom Flume! 

 2023 Season pricing is now available! These are some of the best prices we've seen on the Borealis line!




    Eagle 12 speed Flume Specs (1×12)

    Eagle NX Eagle GX
    Crankset SRAM Eagle NX SRAM Eagle GX
    Crank Arms 175mm Alloy 175 Alloy
    Rear Derailleur RD ENX 1 x 12 RD EGX 1 x 12
    Chain KMC X12 KMC X12
    Cassette PG 1230 11-50 XG 1275 10-50
    Shifters SRAM Eagle NX SRAM Eagle GX
    Brakes SRAM - Select SRAM - Select
    Chain Ring SRAM 30T X-Sync
    Frame Borealis Crestone Carbon
    Fork Borealis Carbon Rigid Fork
    Headset Borealis
    Hubs Borealis: Front 15×150 Rear 12×197
    Rims 26" or 27.5" Sun Ringle Mulefut V2
    Spokes Borealis Straight Gauge
    Nipples Borealis Silver Brass
    Tires Your Choice
    Bar Borealis Carbon Bar (35mm)
    Stem Borealis 50mm or 70mm
    Post Borealis Carbon Seatpost (31.6mm)
    Saddle Borealis
    Grips Borealis
    Bottom Bracket SRAM DUB 100mm
    DT/CS Protector Lizard Skins
    Weight See weight calculator for exact weight.

    S M L XL S M L XL
    EFFECTIVE TOP TUBE 23.02 in 24.02 in 24.8 in 25.59 in 585 mm 610 mm 630 mm 650 mm
    SEAT TUBE CENTER TO TOP 15 in 17.01 in 19.06 in 21.02 in 381 mm 432 mm 484 mm 534 mm
    HEAD TUBE 4.13 in 4.72 in 5.31 in 5.91 in 105 mm 120 mm 135 mm 150 mm
    SEAT TUBE ANGLE 73 deg 73 deg 73 deg 73 deg 73 deg 73 deg 73 deg 73 deg
    HEAD TUBE ANGLE 70 deg 70 deg 70 deg 70 deg 70 deg 70 deg 70 deg 70 deg
    STANDOVER HEIGHT Due to various rim and tire options stand over is not identified.
    CHAINSTAY 17.91 in 17.91 in 17.91 in 17.91 in 455 mm 455 mm 455 mm 455 mm
    BB DROP 2.36 in 2.36 in 2.36 in 2.36 in 60 mm 60 mm 60 mm 60 mm
    REACH 16.04 in 16.65 in 17.22 in 17.76 in 407.3 mm 423 mm 437.5 mm 451.2 mm
    STACK 23.50 in 24.05 in 24.61 in 25.16 in 597 mm 610.9 mm 625 mm 639.1 mm
    What Size? Shipping View full details