News of a Specialized Demo 29 is not surprising. What we all want to know is will 29er-hater Loic Bruni ride one at Les Gets this weekend?

>>> Rachel Atherton’s record breaking 74th World Cup podium

Specialized Demo Expert 29

MSRP: £4,499
All-new frame design
Premium M5 alloy frame with 200mm of travel
Style-Specific (S3) DH Geometry, threaded BB, internal cable routing, 148mm spacing
RockShox BoXXer Select 29 fork
RockShox Super Deluxe Coil Select Plus, trunnion-mount rear shock
SRAM Code R 4-piston disc brakes
SRAM GX DH 7-speed drivetrain

Specialized Demo Race 29

MSRP: £6,499
All-new frame design
Premium M5 alloy frame with 200mm of travel
Style-Specific (S3) DH Geometry, threaded BB, internal cable routing, 148mm spacing
Öhlins DH 29 fork
Custom Öhlins TTX, trunnion-mount rear shock
SRAM Code RSC 4-piston disc brakes
SRAM X0 DH 7-speed drivetrain

Specialized Demo Race 29 frameset

MSRP: £2,749
All-new frame design
Premium M5 alloy frame with 200mm of travel
Style-Specific (S3) DH Geometry, threaded BB, internal cable routing, 148mm spacing
Custom Öhlins TTX, trunnion-mount rear shock
Style-Specific (S3) DH Geometry, threaded BB, internal cable routing

Specialized Demo 29 press release

Introducing the Demo 29

The legendary Demo 8 already delivered plenty of World Cup podiums and World Championship titles. But how do you improve on that? You rework every inch of the beast to wring out even better suspension performance and efficiency.

Introducing the Demo 29—a bike that immediately raced to the top of the podium at its World Cup debut. Then promptly started winning some more.

New chassis, new geometry, and radically new suspension kinematics.

It’s Full-Gas. Full-Fast.

Incredibly Smooth on Square-Edged Hits

Scientifically speaking, square-edged impacts suck. They cause your rear wheel to momentarily hang-up on impact. The impact your suspension should be absorbing is, instead, transferred to you and your frame. That means more fatigue and less speed. But by giving the Demo 29 a more rearward axle path, we’ve minimized that rear wheel hang-up on square-edged hits. Instant speed.

Greater Control While Braking

Imagine: You grab a handful of brake, your weight pitches forward, and your rear wheel loses traction precisely when you need to be low, centered, and in charge. We’ve built in just the right amount of anti-rise on the Demo 29, so when you need to come to a quick stop, you stay stable and in control.

Even Faster on Pedaling Sections

The Demo 29 converts every bit of your pedaling power into speed. The bike’s new kinematics allow for just the right amount of anti-squat. Or to put a finer point on it, you crank on the pedals and it rips forward instead of bobbing around uncontrollably and slowing you down.

Planted and Confident

Low is fast. That is, a low a center of gravity makes you more stable at high speeds. The Demo 29’s new linkage places shock mass as low and forward as possible on the frame, giving the bike both an ideal axle path and an incredibly planted and confident feel.

Maximum Rear Suspension Durability

The Demo 29’s new shock linkage not only places weight low on the frame, it also enabled us to isolate the rear shock from side-loads, which reduces wear and tear on the shock. What’s more, the Demo 29’s trunnion-mount shock features extra bushing overlap, further boosting longevity.

Dialed Geometry

We specifically designed the Demo 29’s geometry to create a ride that’s both fast and playful. The bike’s shorter head tube keeps handlebar height in the sweet spot while its 350-millimeter bottom bracket height strikes a nice balance between cornering control and ground clearance.

WHAT WAS SPECIALIZED TRYING TO ACHIEVE WITH THE REDESIGN OF THE DEMO?

Make the bike fast and make it plush. That, for starters, means better momentum carry. Going 29er, therefore, made immediate sense. But it also raised a challenge: It’s harder to get a more rearward axle path with the bigger (29) rear wheel. We also knew we wanted to give the new Demo a more rearward axle path to reduce rear wheel hang up on square-edged hits. You lose momentum, after all, if your rear wheel is hanging up on big hits. We wanted our cake and we wanted to eat it too, and that meant we were in for a signi cant redesign.

HOW EXACTLY DID YOU ACHIEVE THAT MORE REARWARD AXLE PATH?

It required a significant change to the Demo’s kinematics. The new main pivot placement was the primary contributor to getting that more rearward axle path, and it also explains the longer chainstays.

IF A “MORE REARWARD AXLE PATH” IS BETTER AT ALLOWING THE REAR WHEEL TO MOVE AWAY FROM—AND THEN OVER—BIG, SQUARE-EDGED HITS, THEN WHY DIDN’T YOU GO EVEN MORE REARWARD?

We weren’t interested in chasing one ride characteristic at the expense of other important ride traits. Or to put a ner point on it—we wanted the right balance.

If you go too far rearward, you start getting excessive amounts of chain growth and that, in turn, can give you excessive amounts of pedal kickback…which affects your pedaling performance. If the rear axle is traveling too far rearward on big hits, you also wind up with your geo (wheelbase in particular) changing noticeably and distractingly when you’re in the middle of the most technical sections of a DH track.

And while rearward axle paths can feel great on some big hits, they can lead a bike to feel less supple on smaller bumps. So, you gain speed in one section of the track, but you’re slower on other sections of the downhill. We weren’t interested in designing the Demo to be faster on just one section of a DH track—it’s about being faster across the widest range of conditions possible. And that means nding the right balance of suspension characteristics.

SOME OF THE PROBLEMS THAT RESULT FROM HAVING TOO REARWARD OF AN AXLE PATH—LIKE IMMENSE AMOUNTS OF CHAIN GROWTH (AND THE RESULTING PEDAL KICKBACK)—CAN BE RESOLVED BY PUTTING AN IDLER PULLEY ON THE BIKE. WHY DIDN’T YOU MAKE THE AXLE PATH EVEN MORE REARWARD AND SIMPLY EQUIP THE DEMO 29 WITH AN IDLER PULLEY?

Idler pulleys can cancel out excessive chain growth, but they do so while introducing other less-awesome traits, like extra friction in the drivetrain. On top of that, while excessive chain growth can be a problem, the right amount of chain growth can help create effective anti-squat and improve pedaling performance, which is a plus any time you have to sprint during a race.
Obviously, you can win races with an idler pulley—it’s being done and we’re not going to slag other brands for going that route. Idler pulleys, however, weren’t a direction we wanted to go with the Demo.

YOU SAY YOU BUILT MORE ANTI-RISE INTO THE NEW DEMO. HOW MUCH MORE ANTI-RISE DID YOU ADD TO THE NEW DEMO?

We increased anti-rise on the new Demo by 70%.

We spent a lot of time working with Loïc Bruni, and the rest of the team, to dial-in the ideal amount of anti-rise. Loïc, in particular, came to the Demo 8 after competing on a single-pivot bike that featured much more anti-rise than his Demo 8.

We always felt that the Demo 8’s low levels of anti-rise contributed to its rear suspension’s great sensitivity. The suspension stayed active when you were on the brakes, and we liked that. The bike did, however, have a tendency to pitch you forward slightly when you grabbed a lot of brake. On steeper tracks, that can be unsettling. You could clearly adjust to that trait and ride fast as hell. Loïc, Gwin, Brosnan, Finn, Miranda Miller, and tons of riders around the world proved that point.

That said, working with Loïc, and many other riders, convinced us that we could achieve more of a balance on the Demo when it came to anti-rise. If the rider is adjusting their ride position—shifting rearward when they hits the brakes—that can be less than awesome when you have a 29-inch wheel out back. And as we mentioned earlier, we were interested in improving momentum carry with the bigger rear wheel. Adding more anti-rise to the Demo made sense.

YOU CAN BUILD TOO MUCH ANTI-RISE INTO A BIKE. IF HITTING THE BRAKES SUCKS THE BIKE DOWN DEEPLY INTO ITS TRAVEL, YOU CAN REDUCE THE REAR SUSPENSION’S SENSITIVITY, MAKING THE BIKE FEEL HARSH. WHAT’D YOU DO TO AVOID THAT PITFALL?

Again, it’s a balance. We didn’t go overboard with the anti-rise and that’s why the new Demo feels more planted than before when you’re on the brakes, but also feels smooth when you’re hitting the stoppers in rough sections. The short answer is that we spent a long time working with our riders to find that balance.

YOU SAY YOU BUILT IN MORE ANTI-SQUAT. HOW MUCH OF A CHANGE ARE WE TALKING ABOUT?

We didn’t initially go chasing anti-squat (that is, attempting to get more of it) when we set out to design the new Demo. That said, since anti-squat is affected by a host of factors, including instant center, rear axle path, and chain forces, we wound
up with a higher anti-squat value in this new Demo than was ever featured in its predecessors. Anti-squat increased (Demo 8 to the new Demo 29) by about 300%. The feedback from the team was unanimous—they liked how the increased anti- squat improved the Demo’s pedaling performance.

WHAT ABOUT THE LEVERAGE CURVE ON THE NEW DEMO? HAS IT CHANGED?

The leverage curve is more progressive now. We spent years testing custom links on the Demo 8 (first with Gwin and later with Loïc), which brought us to the conclusion that the Demo could be improved with increased bottom-out control.

WHY 29-INCH WHEELS?

Big wheels better maintain their momentum in rough sections than smaller wheels. Go, Science.

YOU’RE RELEASING THE NEW DEMO WITH 29-INCH WHEELS FRONT AND REAR, BUT YOUR DH TEAM IS RACING THE BIKE WITH A 27.5 REAR WHEEL. WHAT’S THE STORY THERE?

When we developed the new Demo, the UCI rules required that riders race on equal- sized wheels. Because, you know, UCI….

That wheel size ruling changed recently and, as a result, you’re seeing teams (including our own) experiment with different wheel size combinations on different tracks. You can get farther off the back on really steep tracks with a smaller rear wheel. You can get less hang up over fast, open, and rough sections with bigger wheels.

ARE YOU GOING TO OFFER THE DEMO WITH A 27.5 REAR WHEEL OR OFFER A KIT THAT LETS PEOPLE RUN THE BIKE BOTH WAYS?

We’ll see. Our goal was to create the fastest DH bike possible and that meant going full 29. Given the new UCI ruling, we’re working with our team to test the split (29/27.5) wheel size con figuration. The Demo’s design has always been shaped by racing. We’ll see what the season and the future holds. The Demo will always evolve.

WHAT WERE YOU AIMING TO ACHIEVE WITH THE GEO CHANGE?

We’re constantly trying to achieve more rider comfort at even higher speeds, and we’re doing that, while taking into consideration, how DH tracks around the world are evolving.

So, for starters, we slightly increased the reach. Working with a trail number we were comfortable with, we relaxed the head angle slightly and worked with Öhlins on the proper offset for the crowns. We tested a wide range of offsets—all the way from high 40s to low 60s. Ultimately, we found maximum traction, control, and comfort with a 58-millimeter offset.

We increased stack height a bit, after paying close attention to rider setup, and the constant search for comfort on modern race tracks. Taking the Demo’s new ride characteristics into account, we also raised the bottom bracket slightly. The goal was to balance the bike’s ability to corner, yet not hit pedals in pedaling sections of DH tracks. The rear-end has grown 20mm. Twenty-nine-inch wheels, and our team’s demand for high-speed stability and great cornering traction, had an impact on that.

THIS THING IS ALUMINUM. WHY ISN’T THERE A CARBON DEMO 29?

We build the Demo for the world’s fastest racers. Demo is our platform for innovation, and that means it’s undergoing constant development as our riders try to squeeze out every possible bit of speed. The Demo is R&D in motion, and that means you can expect it to evolve throughout the season. Alloy gives us that flexibility to weld different variations and constantly tweak and refine.