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1 Review
On-One DeeDar SRAM GX Eagle Mountain Bike On-One DeeDar SRAM GX Eagle Mountain Bike
In stock
Bikes showing as in stock we aim to build on Thursday 13th of December.
Don't forget to choose your custom options, and look at the amazing deals on wheels too!

Pre-ordered bikes will take a little longer, but we'll keep you in the loop
From £1,099.99
In stock

The On-One DeeDar takes the 650b hardcore hardtail concept to the next level- It's the hooligan hardtail. Longer, lower and slack enough to tackle anything. Its what we wanted to ride, an Enduro sled, with a hardtail, made for dirty, bike riding fun. Now with a 5:1 gear spread and 12 gears we've never ridden a more versatile hardtail.

  • Double butted cro-mo tubing, long low and slack
  • X-Fusion RL2 140mm fork
  • SRAM Eagle GX1 1x12 drivetrain
  • 27.5" Wheelset Full Description


Frame: We love uncomplicated, fuss free, fun-filled bikes at On-One, that's why we originally came up with the hardcore hardtail concept. Over the years, we've refined the theme through the 456, 456Evo and most recently the 45650b- now we've completely reimagined it with the DeeDar. Think what would happen if you took a modern full-suspension Enduro sled and got rid of all the complications to just leave the raw essence of what made it special. Well, we've done exactly that.

We've created a steel hardtail that mimics the modern progressive geometry seen on the most capable full-suspension bikes. We've gone long, with plenty of cockpit room but still allowing you to run a short stem. We've gone low, dropping the BB height for maximum stability and shortening the rear stays to give you a more playful ride. We've gone slack, tilting out the head angle to an awe-inspiring 65.5 degrees that simply eats up the trails and inspires huge confidence at speed when the path points downhill.

Weve fitted Stealth Dropper post routing because we know thats what you expect- because its what we expect too. Check out your dropper post options in the upgrade section.The back end is designed just for 1X drivetrains, so weve been able to maximize the tyre clearance while still keeping the back end ultra short and playful. The rear drops are bolt in units as well. So youll be able to swap between different axle options once all this wheel standards nonsense settles down- we like 12x 142 for now so thats what you get out of the box.

Groupset: SRAM Eagle GX1 SRAM Eagle drivetrains are the only 1x drivetrains that are fully system engineered for optimal performance. Eagle drivetrains are designed, tested and proven to deliver the lightest, highest-performing, most durable systems for all riders on any trail.

With 12 gears, a 500% gear spread as well as everything else that makes SRAM's 1x drivetrains the best choice in the business Eagle GX brings unheard of performance down to a price point that we can all afford. We've long been fans of the simpler one-up-front set-up, and this groupset manages to eliminate all those sore points that prevented previous perfection. Chain retention is faultless thanks to the X-Sync chainring; no more deflected chains, strong performance in muddy conditions - it's next level. Shifting is on-point and solid thanks to the horizontal parallelogram X-Horizon rear mech design. Doesn't mean much? Well, in performance terms it's faster, reduces shift force and does away with ghost shifting and chain slap, whilst increasing stability and precision across the entire range of the 10-50T cassette. This is the best performing groupset we've ever ridden

Suspension fork: X-Fusion Velvet RL2 140mm. A great air-sprung fork with 32mm stanchions and lockout control. Easily adjustable for spring rate and rebound damping the X-Fusion Velvet is all many riders will ever need.

Buy, ride, smile. It's that simple, it's how bikes should be.

Factory Jackson DeeDar Review

  • Weight:28.3lbs (Med)/ul>

    The DEEDAR has been EN tested with forks up to 160mm in length. We do not recommend using forks longer with more than 160mm travel as this may void your warranty.

    Please Note: All customisable options will be fitted by our trained mechanics.

Full Spec

Custom options available
On components showing this spanner
Brake Setup UK Brake Lever Setup Rear Brake Left
Fork X-Fusion Velvet 26" / 27.5" RL2 Fork / 140mm / Black
Handlebar El Guapo Saloon Riser Handlebar / 31.8mm / Grey
Saddle WTB Volt Sport Saddle / Black
Seatpost El Guapo Bronco Seatpost (Grey Logo) / 31.6mm
Stem El Guapo Stallion Stem / 60mm / Grey
Tyres Geax Saguaro MTB Folding Tyre / 27.5 inch / Black / 2.2 inch
Inner Tube Vavert 27.5" Inner Tube / 1.75" - 2.125" / Presta / 48mm  
Brake spare SRAM Hydraulic Hose Fitting Kit Includes Barb And Olive / Single Olive  
Brake spare SRAM Hydraulic Hose Fitting Kit Includes Barb And Olive / Single Barb  
Head Set Planet X Headset Spacer Set / 1 1/8" / 15mm + 10mm + 5mm / Black  
Seat Clamp Selcof Forged Alloy Bolt Up Seatclamp / 34.9 mm  
Head Set FSA Top Cap And Star Nut  
Bar Tape / Grips On-One Bob On Lock-On Grips / Black  
Brake spare Avid MMX Matchmaker Clamp Black / Right  
Brake spare Avid MMX Matchmaker Clamp Black / Left  
Head Set Selcof Semi-Integrated Cup Cartridge Bearing Headset For Tapered 1 1/8th 1.5 Fork Steerer  
Brake spare Avid Centreline Disc Brake Rotor / 160mm Centrelock  
Bottom Bracket SRAM GXP XR Bottom Bracket (With Spacers) / 68/73mm  
Brake spare Avid Centreline Disc Brake Rotor / 180mm Centrelock  
Chain SRAM GX Eagle 12 Speed Chain / 126 Links  
Brake SRAM Guide R Hydraulic Disc Brake / Rear / 1600mm / 20 Post to IS  
Brake SRAM Guide R Hydraulic Disc Brake / Front / 900mm / Post Mount  
Crank Set Truvativ Descendant 7K Eagle Direct Mount Chainset GXP / 170mm / 32 Tooth  
Gear Levers SRAM GX Eagle Trigger Shifter / 12 Speed / Right Hand  
Cassette SRAM XG-1275 Eagle 12 Speed Cassette / 10 - 50 Tooth  
Wheel Pair Fulcrum Red Zone 700 27.5" Centre Lock MTB Wheelset / Front 15mm / Rear 12 x 142mm / XD  
Rear Mech SRAM GX Eagle Rear Mech / 1 x 12 Speed  

Key features

DeeDar Hardtail Frame
The On-One DeeDar takes the 650b hardcore hardtail concept to the next level - It's the hooligan hardtail. We designed it for how we wanted to ride it. Winch and Plummet hardtail geometry to get you up the ups, and smash down the downs.
SRAM Eagle GX1
12 gears, 500% gear range, 10-50t, lighter, faster, better. Eagle GX1 is unstoppable, it's the most versatile groupset on the market and perfect for any mountain bike.
Direct To Customer
At Planet X we supply everything we make direct to customer, there's no middle men or wholesalers adding anything to the cost. That's why we're able to offer you unmatched value for money- straight from our warehouse to your door
Yorkshire Born and Bred
Our bikes are designed, tested and assembled in Yorkshire. Every model is put through its paces across the toughest road or off-road routes that the Peak District has to offer. Just like us, they are Yorkshire Born and Bred



Size & Specs

Bike frame geometry
AHead Angle (degrees)65.565.565.5
B Head Tube (mm)100110120
C Top Tube C-C Effective(mm)575600625
D Seat Tube Angle (degrees)
E Seat Tube C-T (mm)406444482
F Chainstays (mm)425425425
G BB Drop (mm)333333
I Stack (mm)589598607
J Reach (mm)394417439
L Fork Length (mm)524524524
M Trail (mm)444444
O Wheelbase (mm)110911351161

Buying a bike from Planet X?

Why are prices so low?
Our prices are lower than the competition because we sell direct to you the customer; there are no middlemen to take a slice of the price you pay. We design and build everything ourselves so you get exactly what you pay for and that includes amazing service and unrivalled value for money.

How it works
You can buy from us in three different ways. You can call into one of our showrooms and try the bike you want before you place your order. You can order online via our website, or if you're too busy to call into the shop but would like advice on sizing and specifications then you can email or call our customer service dept. You'll receive the same great service no matter how you buy.

Buying online in confidence
Simply select your frame size and colour below and choose from the range of customisable options. Your bike will then be passed to one of our expert mechanics to build YOUR bike exactly the way YOU want it.

Buy in confidence

Crash replacement policy

2 year warranty

Custom built to your specifications

Built to order in the UK
Built to order in the UK

We design and assemble every bike we sell right here in Yorskhire. We work with the leading component vendors and fabrication facilities  to create bikes of unrivalled performance and value for money.

Can't see the upgrades you want on your bike? Give us a call today and we can build the custom bike of your dreams.

Need help? E-Mail our technical experts

[email protected]

Custom build option available
add to basket and customise
Build your bike in 3 simple steps.
Step 1: Select bike size and colour (by choosing a frame)
Frame View size guide Stock
16 inch Matt Black 16 inch Matt Black £1,099.99 In Stock
17 inch Matt Black 17 inch Matt Black £1,099.99 In Stock
19 inch Matt Black 19 inch Matt Black £1,099.99 Sold Out
Step 2: Choose your options

Need help?

Contact our technical experts

Choose Components

Brake Setup
UK Brake Lever Setup Rear Brake Left  FREE i
EURO - USA DISC & EXO3 Brake Lever Setup Rear Brake Right £50.00 i
X-Fusion Velvet 26"27.5" RL2 Fork | 140mm | White £10.00 i
X-Fusion Velvet 26"27.5" RL2 Fork | 140mm | Black  FREE i
Rockshox Recon RL Solo Air Fork140mm | Diffusion Black | 27.5" x 15mm Thru | Crown Adjust £30.00 i
Rockshox Recon RL Solo Air Fork140mm | Diff Black | Fast Black | 27.5" x 15mm Thru | Crown Adjust £80.00 i
On-One DeeDar 27.5 Steel Hardtail Frame17 inch | Matt Black  FREE i
On-One DeeDar 27.5 Steel Hardtail Frame16 inch | Matt Black  FREE i
Handlebar Our standard build is usually perfect but you can choose a bar that suits your needs.
El Guapo Saloon Riser Handlebar31.8mm | Grey  FREE i
On-One Knuckleball Carbon HandlebarHard | Black | 777mm £45.00 i
On-One Knuckleball Carbon HandlebarHard | Black | 747mm £45.00 i
On-One Knuckleball Carbon HandlebarChewy | Black | 747mm £45.00 i
Saddle Have a preference on saddle design or simply want a lighter saddle? Upgrade now!
WTB Volt Sport SaddleBlack  FREE i
On-One Bignose Evo SaddleCroMo Rail | Black with Black Logo £10.00 i
Prologo Zero 2 SaddleTirox | Black £40.00 i
San Marco Shortfit Racing SaddleBlack | Xsilite £50.00 i
El Guapo Bronco Seatpost (Grey Logo)31.6mm  FREE i
Rockshox Reverb Stealth Dropper Seatpost31.6mm | 2000mm Right | 390mm | 125mm £150.00 i
Stem Our standard build is normally great, but you can change the geometry of your ride and get the right fit - choose the stem length that's right for you.
El Guapo Stallion Stem60mm | Grey  FREE i
El Guapo Stallion Stem50mm | Grey £5.00 i
On-One Hot Box Stem70mm | Polished Black | 7 degrees | 31.8mm Clamp £5.00 i
El Guapo Outlaw Stem31.8mm | 35mm £12.00 i
El Guapo Outlaw Stem31.8mm | 45mm £12.00 i
Vittoria Saguaro Folding Tyre27.5 inch | 2.0 inch | Black  FREE i
Geax Saguaro MTB Folding Tyre27.5 inch | Black | 2.2 inch  FREE i
Continental Trail King 27.5" SL Folding Tyre2.2 £20.00 i
WTB Trail Boss TyreFolding Bead | 27.5 inch | 2.25 | TCS Light High Grip Tyre £25.00 i
Continental Trail King 27.5" SL Folding Tyre2.4 £25.00 i
On-One Smorgasbord 650b Tubeless Ready TyreTrail Extreme | Folding | 60/42a | 27.5" x 2.25" £30.00 i
On-One Chunky Monkey 650b Tubeless Ready TyreTrail Extreme | Folding | 50/42a | 27.5" x 2.4" £30.00 i

Optional Accessories

Bottle Cage We're famous for our bottle cages, don't miss out and treat your yourself to a bottle cage for your new bike.
Planet X Nightwolf Plastic Bottle CageBlack £4.99 i
Planet X Stainless Steel Bottle CageBrushed £9.99 i
Selcof Carbon BottlecageBlack £19.99 i

Rest of range