Specialized Demo DH Custom Build

Going downhill as fast as you can is about as pure as mountain biking gets and having a bike thats built specifically for that very purpose is just damn cool.

We had some bits and bobs "lying around" so we thought we would build them into a DH rig for us all to stare at in the shop.

And here it is! A Specialized Demo DH machine with a well thought through (found in a box out back), spec thats actually super high performance and will be faster than you! 

Check out the video to see this awesome, off the shelf custom build! 

Key Components of the Build

Suspension

At the heart of this build are the Öhlins suspension components - the DH 38 M2 forks and the TTX coil M2 shock. As the narrator notes, these are widely regarded as some of the best suspension on the market, with unparalleled tuning capabilities and performance.

The 54mm offset on the forks is a key detail, as it helps to "calm the front end down" at high speeds, providing more stability and control. This is a crucial consideration for a downhill bike that will be pushing the limits of traction and handling.

Cockpit

The cockpit of this bike is outfitted with premium Burgtec components, including the Bryson grips, Bryson riser bar, and direct mount stem. These parts are not only beautifully designed, but also engineered for maximum strength and stiffness - essential qualities for a downhill bike that will be subjected to immense forces.

The 50mm rise on the bars is another thoughtful touch, providing the rider with a more upright, confident position that's well-suited to the steep, technical terrain of downhill racing.

Brakes and Drivetrain

For the brakes, the bike is equipped with Hope Tech Four E4 calipers and Tech 4 levers. Loads of power and adjustment, bike point control, [and] reach control. Massive 220mm rotors provide the stopping power required for high-speed descents.

The drivetrain features a mix of SRAM components, with an XO crankset and cassette paired with a more affordable GX rear derailleur. This is a smart choice, as the rear derailleur is more prone to damage on a downhill bike, so the budget friendly approach over XO just makes good sense on a bike thats going to be abused.

Wheels and Tires

The bike rolls on a set of DT Swiss 240 hubs laced to Roval Traverse HD carbon rims. The carbon construction helps to reduce rotational mass, making the bike feel more "lively" and responsive. The Maxxis Assegai and Maxxis Minion DHR II tires in downhill casing provide the necessary grip and puncture resistance for high-speed, technical terrain.

We went with the Max Grip compound up front for maximum traction, and the Max Terra compound on the rear to provide longer-lasting durability. It's these kinds of thoughtful component selections that elevate this build to the level of a true World Cup-winning machine.

Additional Features and Finishing Touches

The attention to detail on this build extends to the smaller, yet equally important, components and accessories. The RRP mud guard, for example, is a practical addition that will help keep the rider clean and the bike running smoothly, even in the muddiest of conditions.

The Specialized downhill-specific saddle is another standout feature, with its smaller size and textured surface designed to provide the perfect balance of support and control when the rider is aggressively manhandling the bike through the turns.

Finally, the Peaty's tubeless valves and lack of Cushcore inserts demonstrate a thoughtful approach to weight savings and simplicity, prioritizing the bike's performance over unnecessary frills.

The Importance of Geometry

No discussion of a high-performance downhill bike would be complete without a closer look at the geometry. As the narrator explains, the Specialized Demo DH frame features a 62.8-degree head angle and a 446mm reach, which is considered on the shorter side for a downhill bike.

This compact, stable geometry is a deliberate choice, as downhill bikes tend to favor a more centralized, maneuverable feel over pure top-end speed. The longer wheelbase helps to provide stability at high speeds, while the slightly shorter reach keeps the rider's weight distribution more balanced and responsive.

These geometry figures, combined with the bike's other carefully selected components, create a package that is optimized for the demands of downhill racing - offering the perfect blend of control, confidence, and pure, unadulterated speed.

Build Your Own! 

If you've been looking at getting a bike built fully custom then give us a call! We do this day in day out and its our go to favourite thing to do when we are bored. Hence this Specialized Demo build! 

Get in touch to walk through your dream build!