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New for 2017 is Genesis' Zero Disc range which sees the British brand take its carbon fibre race model and give it some tweaks, most notably the addition of disc brakes but there is more to it than that. Let's take a look at what makes the range-topping Zero Disc i such an impressive, lightweight, comfortable race machine.
The Zero was released a few years back as Genesis' entry into the world of carbon fibre race bikes to sit alongside their established Volare, the steel bike that their trade team were racing.
The Zero was designed to be used for the longer stage race where the balance between stiffness and comfort was a little more crucial. More importantly though it makes it a great bike for those who just want to ride fast without actually needing or wanting a license.
The Zero Disc is an evolution of that as with British Cycling still restricting use of disc brakes in races means, for now at least the Zero Disc is aimed squarely at the club rider, weekend warrior and anyone else who just wants to get out there and smash the pedals.
The first thing you notice once you start riding the Zero Disc i is just how light and responsive it is. Okay, at 8.25kg for our medium model it's not exactly a featherweight especially at this price but it rides like a bike much, much lighter.
Acceleration, whether that be on the flat or on the inclines is instant and dealt with in a controlled manner. The Zero Disc i doesn't whip about or feel unsettled on broken tarmac even when you are really stamping on the pedals, a testament to how much compliance they've built into the frame without sacrificing power transfer.
The Zero Disc i follows the tried and tested route of carbon fibre frame manufacture of oversized downtube, bottom bracket area and chainstays while the seatstays especially are very narrow to promote flex.
It uses Pressfit BB86 bottom bracket bearings which have a larger outer diameter than standard. They sit inside the frame, rather than being outboard, so the bottom bracket shell can be wider for increased stiffness. The larger surface area of the bottom bracket shell means the tube junctions can be increased in size too.
The front end isn't immune from a bit of a diameter increase either. Steerer and head tube are tapered. The steerer is 1 1/4in at the bottom for stiffness, narrowing to 1 1/8in at the top to take a standard stem. The handling is stable and very easy to live with and you don't get any surprises.
One of the longer test rides on the Zero Disc saw me head down to Dorset and then along the Jurassic Coast, a twisty lumpy B-road. It's a challenging road with plenty of climbing, bends and descents, it also happened to be 31.8°C and I didn't have a bottle!
I was struggling with dehydration, low blood sugar and fatigue but I wasn't going to let that get in the way of having fun on the descent to sea level. The road was pretty straight with just a slight bend in the middle, nothing too taxing and even in my less than alert state the Genesis just got on with the job even when I was well over the 50mph speed limit.
The steering has a neutral feel to it but it's well-balanced. I only found the Zero Disc i a little wanting when things started to get technical at speed. It lacks the sharpness and engagement of a bike of this geometry, with pretty steep seat and head angles plus a stack to reach ratio of 1.44 which puts it in the performance category.
On the descents, though, the fork stiffness impresses even when you really force those high braking loads through the legs. Genesis have gone for a thru axle so instead of a quick release spindle you get a threaded tube that passes through the first 'dropout' (it's actually a hole through the fork leg), through the wheel axle before it screws into the other fork leg.
On disc-equipped bikes with quick releases and traditional dropouts I've found stopping from 50-60mph can cause the feeling of the whole wheel twisting under load and I'd had to to re-sit the wheel to realign the rotor in the caliper. There is none of that here.
As I said earlier the Zero Disc i focuses on comfort and it makes the bike very easy to ride quickly over a long distance without fatigue kicking in.
Even with that racy position you never feel overly stretched out, neither do you feel too upright. The Genesis seems to sit you in a position that just feels right for the majority of terrain. You can hunker down in the drops if you want to push on and even the most inflexible should be able to maintain it.
The compact style frame has a heavily sloping top tube which exposes a lot of seatpost to flex for added comfort. When paired with those pencil thin seatstays this means the ride has a bit of a steel feel about it: smooth, velvety if you like. You certainly don't get the buzziness associated with a lot of performance carbon framesets.
The Zero Disc has a claimed frameset weight of 1.44kg which is pretty impressive for a frame and fork designed to stand up to the extra loadings of disc brakes. Things look even more impressive when you take into account the aero shaped oversized tubes which often add weight against saving watts in the wind tunnel. It goes a lot of the way to justify the £1799.99 price for the bare frame and fork.
The overall finish of the frameset is impeccable, with a deep paintjob keeping the carbon fibre covered up. I'm rather a fan of the grey colour too.
All the cables, hoses and wires are passed through the frame giving a clean look and protecting them from the elements. It also makes the frame compatible with both mechanical and Di2 shifters. The tube inserts aren't the most elegant I've seen but they keep paint rub at bay.
This 'i' model comes with a full Ultegra Di2 groupset with hydraulic brake levers, flat mount calipers and 160mm rotors. That is an expensive setup especially with those shifters costing more than many mechanical complete groupsets.
The shifting is brilliant and while I can notice a marked difference between Ultegra and Dura Ace mechanical there is little to separate them in their electronic form. A lot of this is helped by the non-series shifters which cover hydraulic Di2 throughout the range, as they need to be able to work with the top end stuff.
A lot of manufacturers have stuck with 140mm rotors front and rear, a setup that I think is perfectly adequate and I really didn't feel any benefit from the larger discs here. In fact, I wasn't overly amazed with the braking as a whole compared to my own system on the Mason with 140mm ColdTech rotors. That is probably more to do with setup preference though.
For gearing the Zero Disc i comes with a semi-compact chainset, 52/36T chainrings paired with an 11-speed, 11-28T cassette. It's a setup I'm a big fan of offering a decent spread of gears across the board for climbing and flat out pace work though you might want to swap to a 50/34T up front if you spend a lot of time in the hills.
The wheels are Fulcrum Racing 5 DBs, the Italian brand's disc-specific wheelset. They are a little average when compared to the frameset they adorn.
At a claimed 1715g they suffer a bit in the hills and blunt acceleration a touch so during testing I stuck on some Mason x Hunt wheels, a little more expensive but 160g lighter which made a real difference to how the Genesis rode and responded.
The Fulcrum's are a solid set of wheels though. You won't have much trouble from them at all in terms of reliability and they are pretty easy to service.
The Continental tyres are much like the wheels, solid and dependable without being truly outstanding anywhere and could really do with better rolling resistance for a frame of this style. Wear levels are good long term from personal experience and so is puncture proofing.
The Zero Disc i costs £3299.99 which is a lot of money. There is a lot of development in that frame, it's a good 'un, plus you've got the electronic/hydraulic groupset which all adds up but I still find the own branded finishing kit at this price a little poor, especially the basic alloy seatpost and cheap feeling, hard saddle.
I'm not expecting carbon (well maybe at the seatpost) but something a little more ground breaking would be a nice touch. Some mid-range Ritchey or Deda components maybe. What would it bring in performance terms? Very little probably but it all adds to the experience in my eyes.
I've ridden quite a few Genesis bikes over the years being one of the first to test the original Equilibrium and also owning a Flyer for the last five years. Over the years I've felt that the range had lost a little of that sparkle, I wasn't overly enamoured by the Equilibrium Ti but for me the Zero Disc is a welcome return to those exiting, responsive, enjoyable early frames.
It might not be the sharpest handling, most engaging ride for those who really like a lot of feedback, but for those who just want to ride very fast, for a very long time in total comfort it's hard to knock.
It's pricey, but it takes on the likes of the more expensive De Rosa Idol Disc with its head held high, although as I say I'd like to see a better level of finishing kit.
The Zero isn't a generic, off the shelf frame so Genesis have the added costs of R&D plus the tooling which for a range of different frame sizes plus forks doesn't come cheap and this goes a long way to justify that overall price.
If you can't quite stretch to the Zero Disc i model, there are four others in the range which should suit most budgets.
Impressive, lightweight, comfortable race machine, deserves better finishing kit
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road.cc test report
Make and model: Genesis Zero Disc i
Size tested: 55
About the bike
State the frame and fork material and method of construction. List the components used to build up the bike.
Frame: 30/40T Monocoque Carbon Road Race Disc w/ Tapered Headtube & Fully Internal Cable Routing
Fork: Genesis Carbon Road Race Disc w/ 1-1/2" - 1-1/8" Tapered Steerer w/ 12mm TA
Headset: Prestine PT-1860C- 616
Shifters: Shimano ST-R785 Di2
Rear Derailleur: Shimano Ultegra RD-6870 Di2
Front Derailleur: Shimano Ultegra FD-6870 Di2
Chainset: Shimano Ultegra FC-6800 - 52-36T
Bottom Bracket: Shimano BB-RS500-PB
Chain: KMC x11
Cassette: Shimano CS-5800-11 / 11-28T
Wheels: Fulcrum Racing 5 DB
Tyres: Continental Grand Sport Race 700x25c
Brakes: Shimano BR-RS805 hydraulic brakes, Shimano SMRT81 160mm rotors
Handlebars: Genesis Tranz-X
Stem: Genesis Code 7
Saddle: Genesis Road Comfort
Seatpost: Genesis Alloy / 27.2x350mm
Tell us what the bike is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about the bike?
"Electronic gearing and hydraulic braking on a thorough-bred race bike. Welcome to the future.
The crème de la crème, the best of the best, the top of the tree. The Zero Disc I combines the best technical wizardry from Shimano with a superlative chassis. If youre looking for a race ready machine that uses the latest technology then this is it. The Ulegtra Di2 groupset make shifting a breeze regardless of the conditions, whilst the hydraulic braking beckons you to dives through corners like never before."
The Zero Disc I is the perfect race bike for the non-racer With British Cycling still not allowing disc brakes) thanks for it's light weight, snappy acceleration and surefooted high speed handling.
Frame and fork
Tell us about the build quality and finish of the frame and fork?
The Disc I's frame and fork is exceptionally well made with a solid and well damped feel that still manages to provide an engaging ride which highlights the skill used for the carbon fibre lay up. The paint job matches being thick and very hardwearing.
Tell us about the materials used in the frame and fork?
A mixture of 30T and 40T grade carbon fibre is used throughout the frame and fork.
Tell us about the geometry of the frame and fork?
This is no endurance style bike, the angles are steep and the geometry pitches it very much at the rider who likes to go hard and fast.
Full details here - http://www.genesisbikes.co.uk/bikes/road/road-performance/zero-disc/zero...
How was the bike in terms of height and reach? How did it compare to other bikes of the same stated size?
For this size the stack and reach measurements give a ratio of 1.44, a touch shorter and longer than a full race bike but not by much.
Riding the bike
Was the bike comfortable to ride? Tell us how you felt about the ride quality.
The Zero Disc sits nicely on that edge of performance/comfort balance with a ride that lets you feel everything without being harsh.
Did the bike feel stiff in the right places? Did any part of the bike feel too stiff or too flexible?
With an oversized bottom half of the frame stiffness is very impressive especially when out of the saddle.
How did the bike transfer power? Did it feel efficient?
The press fit bottom bracket guarantees a large cross sectional area and junctions for each of the tubes which means the frame packs a punch when you really ask it to.
Was there any toe-clip overlap with the front wheel? If so, was it a problem?
How would you describe the steering? Was it lively, neutral or unresponsive? Responsive especially at speed
Tell us some more about the handling. How did the bike feel overall? Did it do particular things well or badly?
The handling of the Zero Disc is impressive. There is plenty of feedback and the whole bike just 'loads up' nicely as you drop it into a bend. It's not the tightest bike I've ridden through the twisty bits but it is a very competent bike that is so easy to ride quickly.
Which components had the most effect (good or bad) on the bike's comfort? would you recommend any changes?
I wasn't a fan of the Genesis saddle with it feeling quite unforgiving at the nose.
Which components had the most effect (good or bad) on the bike's stiffness? would you recommend any changes?
I wouldn't change a thing, the whole bike delivers plenty of stiffness without being harsh.
Which components had the most effect (good or bad) on the bike's efficiency? would you recommend any changes?
For the money the Fulcrum DB wheels offer pretty standard weight and performance but a switch to something lighter like the Mason x Hunt wheels I tried really made an all round difference to performance.
Tell us some more about the drivetrain. Anything you particularly did or didn't like? Any components which didn't work well together?
The hydraulic brake levers/gear shifters are none series which means they are designed to work with Shimano's top flight Dura Ace groupset so as you'd expect shifting is absolutely spot on. The rest of the group works brilliantly offering just the tiniest of differences to DA which makes it a relative bargain.
Wheels and tyres
Tell us some more about the wheels.Did they work well in the conditions you encountered? Would you change the wheels? If so, what for?
The Fulcrum DB range are solid performers throughout and while they might not be the lightest or most exciting to ride they offer a really decent ratio of performance to durability.
Tell us some more about the tyres. Did they work well in the conditions you encountered? Would you change the tyres? If so, what for?
The Continental Grand Sport tyres sit mid-range and while they offer decent rolling resistance and puncture protection, like the wheels upgrade to something lighter for a real performance boost.
Tell us some more about the controls. Any particularly good or bad components? How would the controls work for larger or smaller riders?
The Genesis own brand components are decent enough and offer stiffness but on a three grand bike I'd expect to see something a little more special especially when it comes to the simple alloy seatpost.
Did you enjoy riding the bike? Yes
Would you consider buying the bike? I'd buy the frameset.
Would you recommend the bike to a friend? Yes
Use this box to explain your score
The Zero Disc is a very good bike, it's a pleasure to ride and very easy to live with but it just lacks a little excitement and feedback for a bike of it's racy genre.
About the tester
I usually ride: This month's test bike My best bike is: Mason Definition
I've been riding for: 10-20 years I ride: Every day I would class myself as: Expert
I regularly do the following types of riding: time trialling, commuting, club rides, sportives, fixed/singlespeed,
With 20 years of road cycling and over 150,000 miles in his legs it's safe to say Stu is happiest when on the bike whatever the weather. Since writing his first review for road.cc back in 2009 he has also had a career in engineering including 3D-CAD design and product development, so has a real passion for all of the latest technology coming through in the industry but is also a sucker for a classic steel frame, skinny tyres, rim brakes and a damn good paintjob.
His fascination with gravel bikes is getting out of control too!