Specialized S-Works Demo 8 Custom Build review

Great frame, superb shock, but very high-priced

Our rating 
4.0 out of 5 star rating 4.0
GBP £9,305.00 RRP

Our review

Wishlist kit, a superb shock and a great frame. Tall riders need not apply though – and that price would keep anyone awake at night
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Our custom S-Works Demo 8 build is eye-wateringly – borderline ridiculously – expensive. But everything on this bike is production kit, so any privateer racer can go out and buy the carbon wheels, stem and bar, or get a loan and fork out for the frame and shock.


The Demo is available in frame-only options for £3,500/US$3,500/AU$3,999* – but this fantasy custom build takes the cost up to approx £9,305 all-in (a rough currency conversion gives you figures north of US$15,800/AU$16,800, though these are unlikely to translate 100 percent accurately and would also be affected by individual components’ pricing and availability). The big question is, will all these high-end parts make any difference to the time it takes you to get to the bottom of the hill?

Frame and equipment: custom designed shock, competition-geared kit

Specialized uses its FACT 11M carbon for the mainframe of the top-end Demo, along with a lightweight magnesium link and an alloy back end. The BB height is adjustable, with three settings from 338mm to 353mm. The FSR suspension design incorporates an odd-looking sub-seatstay that means the shock is driven from the chainstays rather than the seatstays, helping to tailor the leverage ratio and lower the bike’s centre of gravity.

The öhlins ttx shock is a top performer that offers a massive amount of composure when the terrain starts to get ugly:
Steve Behr
The Öhlins TTX shock is a top performer that offers a massive amount of composure when the terrain starts to get uglyIt’s in the shock that the magic happens though. A collaboration between Specialized and motor sport suspension legend Öhlins, the TTX has been designed to work specifically with the Demo 8 and keep its 200mm (7.9in) of travel under control. This means it should, in theory at least, only require slight tweaks to get things feeling just right.The shock has 16 clicks of low-speed compression adjustment, just three for high-speed compression and seven for low-speed rebound. Spring rates jump up in smaller-than-average 23lb increments, which is useful for tuning too – our medium frame came with a 388lb spring but we dropped down to 365lb to get it working more effectively. Spherical bearings are used at the shock mounts to help reduce shock shaft binding when slamming into corners – when static, this can make it feel like there’s play in the mounts.
Up front, the limited edition rockshox boxxer world cup holds its own with the superb öhlins shock. its stanchions are coated to increase the fork’s sensitivity and improve traction out on the trail:
Steve Behr
Up front, the limited edition RockShox Boxxer World Cup holds its own with the superb Öhlins shockEvery component bolted to this custom S-Works Demo is designed to give you a competitive edge and ride as fast as possible – and well it should at this sort of money. The limited edition RockShox Boxxer World Cup gets a slippery Black Gold coating on its stanchions to reduce friction, while the carbon ENVE Composites bar and stem cut weight without sacrificing strength or steering precision.SRAM’s X01 DH seven-speed transmission provides punchy, accurate shifting, but clang that rear mech on a rock or stump and you’ll be shelling out big bucks for a new one – not ideal if you’ve just emptied your savings buying the bike. ENVE’s M90 Ten rims are a monster 25mm wide internally, which helps to produce a great tyre profile. They’re ridiculously stiff too and will take a proper hammering.

Ride and handling: silent killer – provided you’re not too tall

The S-Works Demo 8 is silent, accurate and fast – a proper racer’s bike. There’s something a little eerie about the way it patters across the tops of braking bumps without any noise, but the lack of clatter does inspire confidence.

We’d have preferred a large frame to test rather than a medium because it doesn’t have a particularly long top tube – which begs the question, what are tall riders supposed to do? Still, the medium frame proved lively enough on the hill and the 1,200mm wheelbase and 63-degree head angle provided enough stability when we started trying to really motor.

Specialized s-works demo 8 custom build – the demo’s top tube is fairly short so it’s worth trying one for size before shelling out:
Steve Behr
The Demo’s top tube is fairly short so it’s worth trying one for size before shelling outThe short 430mm chainstays, low BB and stiff ENVE wheels mean that if you commit to a turn and stick your line, you’ll exit at a blistering pace. We did find the super-stiff wheels a little harsh initially, but after a few runs we started to appreciate just how accurate they felt and how quickly they accelerated. Because the bike weighs just 15.79kg (34.81lb), it feels responsive and agile. You can launch over sections of trail with relative ease, and don’t need to worry about where your wheels are going to touch down because the suspension will deal with it. Pick-up out of turns is impressive too, and the low weight makes muscling the bike down slower, more technical descents far less of a chore.The balance struck between the Boxxer World Cup fork and Öhlins shock is what really ekes out the speed though. There’s support at both ends when you need it, but plenty of travel when things get out of shape – and it’s all delivered with composure and control. The TTX shock really is superb, and it’s easy to get tuned in too, which is always a bonus. At lower speeds it feels good, but it’s when you push it hard that you get the most out of it.

Hammer into an ugly rock garden and the control is spectacular. Smaller chatter is soaked up without fuss and the big hits are dealt with in a controlled, just-focus-on-going-fast kind of way. This means you need to be looking way ahead into the next turn, because this thing covers ground rapidly. You can still feel the FSR back end hang up ever so slightly on occasion when you hit a harsh, square-edged compression seriously hard, but thanks to the impressive TTX damper, this is never really a worry.

Batter this derailleur against a rock and your wallet may be squealing in pain:
Steve Behr

Batter this derailleur against a rock and your wallet may be squealing in pain


So does the speed, control and handling justify the stratospheric price? In places, yes. The frame, shock and fork are certainly worth considering if you’re looking to compete seriously and are after that performance edge. There are other areas where we might think otherwise though. If we were racing, would we want to stick a rear derailleur this costly on our bikes? Probably not. Although the X01 DH works well, crashing in downhill is just part of the game and the occasional bent derailleur is almost inevitable.

Product Specifications


Name S-Works Demo 8 Custom Build (14)
Brand Specialized

Description Frame-only prices: £3500.0/US$3500/AU$3999
Weight (kg) 15.79
Rims ENVE Composites M90 Ten
Saddle SDG Circuit
Seatpost Thomson Elite
Spoke Type Sapim CX-Ray
Shifters SRAM X01 DH
Stem ENVE Composites Direct Mount 50, 50mm
Weight (lb) 31.81
Rear Tyre Maxxis Shorty 3C Maxx Grip 26x2.4in
Bottom Bracket Height (in) 13.58
Chainstays (in) 16.93
Seat Tube (in) 16.73
Standover Height (in) 28.35
Top Tube (in) 22.84
Wheelbase (in) 47.24
Rear Wheel Weight 2600
Rear Shock Öhlins TTX 22M, 200mm (7.9in) travel
Available Sizes S M L
Frame Material FACT 11M carbon
Bottom Bracket SRAM PF30
Brakes SRAM Code
Cassette SRAM MINI BLOCK X-DOME, 10-24t
Chain SRAM XX1
Cranks SRAM X01 DH
Fork RockShox Boxxer World Cup custom w/ Black Gold stanchion coating, 200mm (7.9in) travel
Front Hub Chris King MTB
Rear Hub Chris King MTB
Front Tyre Maxxis Shorty 3C Maxx Grip 26x2.4in
Front Wheel Weight 2300
Grips/Tape SRAM lock-on
Handlebar ENVE Composites DH, 800mm
Headset Type Integrated
Rear Derailleur SRAM X01 DH 7-speed
Frame size tested M