SLACKR Titanium Mountain Bike

Design Parameters:  Build the most capable trail hardtail that is playful, grin-inducing and built to pedal long trail days.

Introducing the SLACKR, our new 150mm/140mm travel shreddy Ti hardtail that is designed for all-day trail riding. SLACKR comes in 6 sizes, fits a 36T chainring and up to a 29x2.6" tire. Fabricated in-house using Titanium 3/2.5 Aerospace grade domestic tubing, our custom Made in USA 3D Space Yoke, and PMW Sliding dropouts.

The SLACKR rounds out our MTB lineup with a slacker ;) option for riders looking for a playful trail bike.

    • Chumba Custom Tubing: Built of the best certified domestic 3/2.5 Titanium tubing available.

    • The SLACKR stands out from other bikes in the long travel hardtail category with it's short adjustable chainstays and pedal forward seat tube angle.

    • This isn't another long travel park bike disguised as a trail hardtail. Our take on trail geometry positions the rider to be in a powerful all day pedaling position. This is accomplished through careful planning of reach and seat tube angles.

    • Designed to inspire confident play on the trail while the lightweight frame encourages you to ride longer.

    • Strong 6/4 Titanium PMW adjustable sliding dropouts and a 428mm - 448mm chainstay length offers 20mm of wheelbase adjustment fine tuning the bikes feel.

    • The reach is optimized for precise steering with stem lengths between 35mm and 70mm.

    • A balanced bottom bracket drop, positioned to bring out the rest of the geometry, gives clearance to pedal through technical rock gardens while also hooking up in cornering.

    • Chumba Custom Tubing means this bike will exceed your expectations & provide years of reliable trail service. We create a frame that is tuned to you.

    • Paragon Machine Works Titanium sliding dropouts for use with geared or singlespeed drivetrains.

    • Our titanium 3-D chainstay yoke is designed in house & printed in the USA of 6/4 Ti. Shaped for maximum strength & crank/mud/tire clearance. FEA strength tested and heat treated to Rolls Royce Certified standards and to aerospace specifications.

    • S-bend seat-stays offer the perfect blend of compliance, traction & strength.

    • A custom bent seat tube brings together a short rear end, steep seat tube angle & maximum tire clearance.

    • Clean thoughtful cable routing w/ custom options.

    • Flawless frame miters and precision welds. All tubes are heat sunk and argon purged when welded to prevent distortion and material thinning.

    • Machined head tube for tapered or straight forks.

  • The SLACKR mountain bike is designed to be extremely compatible with a wide range of tire sizes, hub options and fork lengths. Frames come with dropout inserts, rear axle and seatpost clamp.

    Fork Travel: Optimized for 150mm - 140mm travel suspension forks. 44mm offset recommended.

    Suggested Stem Lengths: 35-50mm

    Frame Weight: Right around 4.5 lbs

    Headset S.H.I.S.: ZS44 Upper/ EC44 Lower for 1.5” Tapered or 1 1/8” Straight Forks

    Hub Spacing: 148x12 Boost

    PMW Sliding Dropout Options: Geared, single speed, SRAM Transmission (your choice of inserts comes w/frame)

    Rear Axle: 148x12x1.5 thread pitch (170mm total length) (comes with frame)

    Max Tire Clearances: 2.6” on a 36mm rim

    Bottom Bracket: 73mm Threaded External Cup T47

    Chainring max/Chain-line: 1x 36T oval or 38T round on 51/52mm Boost chain-line, 55mm for SRAM Transmission

    Seat Post: Post 31.6mm, can be shimmed for smaller posts

    Seat Post Clamp: 34.9mm (comes w/frame)

    Dropper Port: Reinforced 6/4 Titanium dropper port on non-driveside w/ rubber housing guide

    Cable Routing: Standard cable routing goes under the down tube via PMW bolt on cable guides and then onto the chain-stays. (or options for custom routing)

    H20 Capacity: 3 bottles on Sizes XL, L, & M, 2 bottles on small (or options for less)

    Rack mounts: Old Man Mountain racks - a USA made thru-axle mounted rack that can hold up to 70lbs. It is more secure for the rack and cargo, and it better protects the frame than a traditionally mounted rack.

SLACKR Titanium MTB - Frame, Frame & Fork or Custom Build Deposit
from $3,995.00

  • Handmade to order, custom geometry is available.

  • Add a complete build kit and save $500 on your frame!

  • Add a fork to a frame for $50-$200 in savings!

SLACKR Titanium Frame Customizations
from $0.00

Frame Customizations

Add custom geo, mounts & more. Your choice of cable routing (internal or external) and Internal dropper post compatibility is included w/ every SLACKR Ti frame. Internal routing makes the cleanest singlespeed or AXS wireless system with the option to remove the derailleur guides.

“All of our complete bikes are built with a custom selection of components. We pride ourselves on listening, understanding your riding goals & working with you to craft the perfect blend of components & customizations.”
— Chumba USA | support@chumbausa.com

SLACKR Titanium Geometry Charts: Sagged & Unsagged in 6 sizes S - XL

150mm Fork Sagged 20%

Measurement S S/M M M/L L XL
Suggested Rider <5'7" 5'7" - 5'8" 5'8" - 5'10" 5'10" - 6' 6' - 6'2 6'2>
Suggested Stem Length 32-50mm 32-50mm 32-50mm 32-50mm 32-50mm 32-50mm
Effective Top Tube 602 613 625 637 650 676
Head Tube Angle 65.8° 65.8° 65.8° 65.8° 65.8° 65.7°
Head Tube Length 95 95 100 105 110 130
Effective Seat Tube Angle 76.5° 76.5° 76.4° 76.4° 76.4° 76.3°
Seat Tube Length 15" 15.75" 16.25" 17.25" 17.75" 20"
Chainstay Length 420-440 428-448 428-448 428-448 428-448 428-448
Bottom Bracket Drop 65 63 63 62 62 58
Wheelbase 1163-1183 1175-1195 1188-1208 1201-1221 1214-1234 1250-1270
Standover Height 29" 29.7" 30" 30.8" 31.2" 33"
Reach 438 451 461 471 483 509
Front Center 743 755 767 780 793 828
Stack 629 627 631 636 640 654
Est. Max Seatpost Insertion 200 190 210 232 242 292

With 150mm Fork Un-sagged

Measurement S S/M M M/L L XL
Suggested Rider <5'7" 5'7" - 5'8" 5'8" - 5'10" 5'10" - 6' 6' - 6'2 6'2>
Suggested Stem Length 32-50mm 32-50mm 32-50mm 32-50mm 32-50mm 32-50mm
Effective Top Tube 606 618 630 642 655 680
Head Tube Angle 64.5° 64.5° 64.5° 64.5° 64.5° 64.5°
Head Tube Length 95 95 100 105 110 130
Effective Seat Tube Angle 75.2° 75.2° 75.2° 75.2° 75.2° 75.2°
Seat Tube Length 15" 15.75" 16.25" 17.25" 17.75" 19.75"
Chainstay Length 420-440 428-448 428-448 428-448 428-448 428-448
Bottom Bracket Drop 55 53 53 53 53 49
Wheelbase 1175-1195 1188-1208 1201-1221 1213-1233 1227-1247 1262-1282
Standover Height 29" 29.7" 30" 30.8" 31.2" 33"
Reach 423 436 446 457 468 494
Front Center 753 765 778 790 804 838
Stack 639 637 642 646 651 665
Est. Max Seatpost Insertion* 200 190 210 232 242 292

Axle to Crown (A2C) Fork Measurements

  • Cane Creek Helm 150mm 29er fork, 44mm offset

  • A2C: Un-sagged: 563mm / Sagged: 533mm

Standover/Effective Seat Tube Angle

  • Standover is measured 90mm forward of the bottom bracket, using a 29x2.4 tire for reference.

  • Effective seat tube angle is calculated from average saddle heights and placements per size.

  • The range is roughly 1º in either direction of the effective angle based on your chosen saddle placement

Frame Finish: We’ll plan this with you after ordering

 

Ordering

The SLACKR Titanium 29er is available as a frame only, frame set, in complete build kits, and partial builds. Custom component configurations can be quoted on request here: Chumba Custom

You can order a SLACKR direct from Chumba over the website using the drop-downs on this page, over the phone, in person @ our Headquarters or from an approved Chumba Dealer. We welcome calls (512) 494-4944 and emails for immediate questions.