• frontier 29er hardtail with rigid forks in white crayon
  • frontier 29er hardtail with rigid forks in black
  • Sonder Frontier SX Eagle Rigid Hobo 29er mountain bike in green forest
    • Special Offer

    Frontier SX Eagle Rigid

    Multi-activity trail bike

    £824 £949

    or from £15 /month V12 logo

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    2

    Customize

    3

    Select Accessories

    Reset

    Quick, lightweight modern mountain bike with SRAM SX Eagle 1x12 groupset and rigid aluminium fork.
    Buy Now. Be Riding Next Week.

    Need help choosing a bike or technical advice?

    • Open a Live Chat
    • Pop into a store 7 days a week
    • Call a Sonder Customer Hero on 01773 417006
    • Email us at support@alpkit.com

    1

    Select Options

    Edit

    • Size
    • Colour
    • Size:

    • Colour:

    2

    Customize

    Edit

    Every Sonder bike is built to order so tell us exactly how you want it. Make any changes you want from the standard build and when you're done, just hit “Add to Bag” at the bottom of the page.

    Handlebar

    Sonder Aspect Riser [OEM]
    Sonder Aspect Riser 780mm

    +£0.00

    Sonder Horizon Flat [OEM]
    Sonder Horizon Flat 720mm

    +£0.00

    Sonder Aspect Riser [OEM]
    Sonder Aspect Riser 780mm

    +£0.00

    sonder horizon carbon flatcar handlebar
    Sonder Horizon Carbon Flat Black

    +£99.99 +£64.99

    sonder aspect carbon flat handlebar flatbar
    Sonder Aspect Carbon Riser 780mm

    +£99.99 +£64.99

    Sonder Confucius
    Sonder Confucius

    +£34.99 +£29.99

    sonder scope handlebars
    Sonder Scope Handlebar 760mm

    +£39.99 +£32.49

    sonder scope cargo handlebars
    Sonder Scope Cargo Handlebar 760mm

    +£74.99 +£59.99

    Saddle

    Sonder Abode [OEM]
    Sonder Abode Black / 138

    +£0.00

    Sonder Zone [OEM]
    Sonder Zone 133 / Black

    +£34.99 +£29.99

    Sonder Zone [OEM]
    Sonder Zone 152 / Black

    +£34.99 +£29.99

    Sonder Kura [OEM]
    Sonder Kura

    +£47.99 +£39.99

    Brooks Cambium C17 Saddle [OEM] / All Weather / Black
    Brooks Cambium C17 Saddle / All Weather / Black

    +£114.99 +£92.49

    Brooks B17 Saddle
    Brooks B17 Saddle Standard / Black

    +£134.99 +£109.99

    Seatpost

    Sonder Seatpost [OEM] 31.6mm
    Sonder Seatpost 31.6mm 400mm

    +£0.00

    X-Fusion Manic Drop Seatpost and Lever
    X-Fusion Manic Drop Seatpost and Lever 31.6mm / 170mm

    +£119.99

    Cane Creek eeSilk+ [OEM]
    Cane Creek eeSilk+ 31.6mm / Alloy

    +£179.99 +£144.99

    Stem

    Sonder Piskie [OEM]
    Sonder Piskie 31.8mm / 35mm

    +£0.00

    Sonder Piskie [OEM]
    Sonder Piskie 31.8mm / 45mm

    +£0.00

    Sonder Piskie [OEM]
    Sonder Piskie 31.8mm / 55mm

    +£0.00

    sonder talo bike stem
    Sonder Talo 35

    +£44.99 +£37.49

    sonder talo bike stem
    Sonder Talo 45mm

    +£44.99 +£37.49

    Tubes

    WTB [OEM] Inner Tube / 27.5 / 2.8-3.0
    WTB Inner Tube / 27.5 / 2.8-3.0

    +£0.00

    Tubeless Tyre Upgrade and Setup
    Tubeless Tyre Upgrade and Setup

    +£44.99

    Wheels

    Sonder Nova 27.5+ [OEM] Wheelset
    Sonder Nova 27.5+ Wheelset Shimano

    +£0.00

    Sonder Nova XC [OEM] Wheelset / UK Build
    Sonder Nova XC Wheelset / UK Build HG

    +£0.00

    Sonder Alpha 27.5 [OEM] Wheelset / UK Build
    Sonder Alpha 27.5 Wheelset / UK Build HG

    +£329.99 +£169.99

    Sonder Alpha 29 XC [OEM] Wheelset / UK Build
    Sonder Alpha 29 XC Wheelset / UK Build HG

    +£329.99 +£169.99

      3

      Select Accessories

      Edit

      Bottle Cages

      No Bottle Cages
      No Bottle Cages (none)

      +£0.00

      Sonder Buzz Wire
      Sonder Buzz Wire Single

      +£5.49 +£4.99

      Sonder Buzz Wire
      Sonder Buzz Wire Pair

      +£10.99 +£8.99

      love mud side blade side loading bottle cage left
      Sonder Sideblade Black / Left Entry

      +£6.99 +£5.99

      love mud side blade side loading bottle cage left and right
      Sonder Sideblade Black / PAIR

      +£9.99 +£7.99

      love mud side blade side loading bottle cage right
      Sonder Sideblade Black / Right Entry

      +£6.99 +£5.99

      Sonder Blade
      Sonder Blade Black

      +£17.99 +£14.99

      Sonder Blade
      Sonder Blade Black / Pair

      +£29.99 +£24.99

      Ti Wire Bottle Cage
      Ti Wire Bottle Cage Single

      +£44.99 +£37.49

      Ti Wire Bottle Cage
      Ti Wire Bottle Cage Pair

      +£79.99 +£64.99

      Front Lights

      No Front Light
      No Front Light (none)

      +£0.00

      Tau
      Tau Front

      +£16.99 +£14.99

      Phase 550
      Phase 550

      +£24.99 +£19.99

      Phase 850
      Phase 850

      +£34.99 +£29.99

      Rear Lights

      No Rear Light
      No Rear Light (none)

      +£0.00

      Lights Accessories

      No Bike Light Accessories
      No Bike Light Accessories (none)

      +£0.00

      alpkit helmet mount bike light gps
      Helmet Mount Black

      +£7.99 +£6.99

      alpkit cockpit bike light gps mount
      Garmin Outfront Mount / Black

      +£24.99 +£19.99

      Mudguards

      No Mudguards
      No Mudguards (none)

      +£0.00

      sonder fender
      Sonder Fender Front MTB

      +£6.99 +£5.99

      Pedals

      No Pedals
      No Pedals (none)

      +£0.00

      Sonder Torque
      Sonder Torque Black

      +£39.99 +£32.49

      reko clipless bike pedal
      Sonder Reko

      +£49.99 +£39.99

      distortion flat mountain bike pedal
      Sonder Distortion

      +£59.99 +£49.99

      sonder slingshot clipless pedal
      Sonder Slingshot Black

      +£79.99 +£64.99

      sonder Jekyll clipless and flat hybrid pedal
      Sonder Jekyll Black

      +£79.99 +£64.99

      Fork

      Frontier Fork [V2]
      Frontier Fork [V2] Crayon

      +£0.00

      Frontier Fork [V2]
      Frontier Fork [V2] Forest

      +£0.00

      Frontier Fork [V2]
      Frontier Fork [V2] Black

      +£0.00

        Initial Price

        Frontier SX Eagle Rigid / Select a frame...
        £824.00

        Extras

        £0.00

        Total Price

        £824.00
        Buy Now. Be Riding Next Week.

        Frontier is our multi-activity hardtail mountain bike. Ride hard at the trail centre, load it up for a midweek bikepacking trip, pocket your passport and continue around the world. With multiple boss mounts on the fork, Frontier is an adaptable off-road explorer.

        The geometry is for long day comfort but it’s no slouch.

        At a glance

        • SRAM SX Eagle 12-speed groupset
        • Frontier Rigid fork
        • Sonder Nova 27.5 / 29" XC wheelset
        • 6061 aluminium frame

        The 6061 aluminium frame provides a durable and stiff chassis giving a responsive kick as you demand power when the slope steepens or enjoy feedback and precision through the corners.

        Available as a fully rigid or with 100mm suspension fork. Set it up for XC race speed or for all day big mile comfort.

        Tyre clearance gives you the choice of 27.5+ or 29in wheelsets. Bolt through 148mm boost rear spacing provides the benefit of stronger, stiffer and more efficient wheels.

        Why SX Eagle?

        SRAM Eagle drivetrains are designed, engineered and manufactured to work as complete drivetrain systems. Its 1x drivetrain is built to be lightweight, strong and intuitive, with the gear range to ride on any terrain.

        SX Eagle provides the same Eagle performance benefits as NX Eagle, but at a lower price point. The main differences stem from the choice of materials and finish options, but functionally SX is fully compatible with SRAMs Eagle groupset.

        Features

        Tuned for all-round capability

        Built for a balance of cross country efficiency and trail centre capability. A favourite with bikepackers looking for all-day comfort and performance.

        Light and clean

        Clean lines thanks to internal cable routing. Frontier also incorporates routing for a dropper seat post. The 6061 aluminium tubing is durable, light, low maintenance and stiff.

        Wider tyres. More grip.

        Extra width between the chainstays gives you the choice of running 27.5+ tyres up to 3 inches or 29 inch tyres up to 2.5 inches.

        Made for stronger wheels

        Designed around bolt through Boost 148mm rear spacing providing the benefit of stronger, stiffer and more efficient wheels.

        Wilderness trail features

        Chainstay mounted disc brakes. And triple bottle mounts.

        Build Spec
        Frameset
        Frame:Frontier Frame | 6061 aluminium
        Fork:Frontier Rigid | aluminium
        Headset:FSA Orbit C-40-ACB
        Groupset
        Shifters:SRAM SX Eagle Trigger | 1x | 12-speed
        Brakes:SRAM Level | Hydraulic | post mount
        Rotors:SRAM Centerline | 180mm (front), 160mm (rear) | 6-bolt
        Rear derailleur:SRAM SX Eagle | Long cage | 12-speed
        Chainset:SRAM SX Eagle | 170mm | 32t
        Cassette:SRAM PG1210 | 11-50t | 12-speed
        Chain:SRAM NX Eagle | 12-speed
        Bottom bracket:SRAM PowerSpline | 73mm | 118mm
        Wheelset
        Wheels:Sonder Nova 27.5" or 29 XC
        Tyres:Goodyear Escape Tubeless | Black | 27.5 X 2.6
        Tubes:WTB | 27.5 x 2.8-3.0"
        Finishing kit
        Handlebars:Sonder Aspect Riser | 780mm
        Stem:Sonder Piskie
        Seatpost:Sonder Seatpost | 31.6mm
        Saddle:Sonder Abode
        Grips:Sonder Clutch | Black
        Weight
        Frame:S: 1.8kg; M: 1.85kg; L: 1.95kg; XL: 1.05kg;
        Build:S: 12.25kg; M: 12.3kg; L: 12.4kg; XL: 12.5kg;
        Pedals not included with full builds
        Specifications are subject to change without notice
        Geometry and Sizing

        Sizing

        It is important to get the right size bike, if the bike fits you well it will be faster, more comfortable and easier to handle.

        Generally we recommend:
        Small: Riders between 5ft 2in and 5ft 7in (157-170cm)
        Medium: Riders between 5ft 6in and 5ft 10in (167-177cm)
        Large: Riders between 5ft 9in and 6ft 2in (175-187cm)
        X-Large: Riders of 6ft 2in + (187cm)

        Size Small Medium Large X-Large
        ST - Seat tube 380 430 480 520
        TT - Top tube 563.1 597.3 621.6 647.3
        HT - Head tube 110 115 130 150
        HA - Head angle 68 68 68 68
        SA - Seat angle 73 73 73 73
        CS - Chainstay 445 445 445 445
        BB - BB drop 50 50 50 50
        FO - Fork offset 51 51 51 51
        WB - Wheelbase 1095.7 1131.3 1157 1184.5
        SO - Stand over 764 793.9 824.6 852.6
        RE - Reach 390 420 440 460
        SK - Stack 566.1 580.1 594 612.5
        Frame Spec
        Frame Weight: S: 1.84kg; M: 1.9kg; L: 1.98kg; XL: 2.03kg
        Rigid Fork Weight - uncut: 1kg
        6061 Aluminium frame
        Optimised for rigid or 100mm suspension forks
        Internal cable routing through downtube
        Bolt Through Boost 148mm rear spacing for wheel strength and optimal chainline
        Fork built around Bolt Through Boost 110mm spacing
        Threaded 73mm BSA BB shell for no-creak assembly
        Chainstay mounted disc brake for clean lines and damage protection
        Triple bottle cage mount on downtube
        Use a seat clamp with integrated mounts for pannier rack compatibility
        Clearance for 3 inch 27.5+ or 2.5 inch 29er tyres
        Reverb Stealth port
        EN 14766 compliant

        • frontier 29er hardtail with rigid forks in white crayon
        • frontier 29er hardtail with rigid forks in black
        • Sonder Frontier SX Eagle Rigid Hobo 29er mountain bike in green forest