Many of us know that Genesis is proud of its British design credentials. And what could be more British than showcasing your new bike and frame on the first day of the Tour of Britain? Genesis did this in 2014 when making the bold move from steel into the world of carbon frames. The Madison-Genesis team turfed up astride the new Zero frame for a whizz round the streets of Liverpool.

Fast forward a year and across the bay to Anglesey; and Genesis are at it again. Messrs Scully, Stewart, Cronshaw, Holmes, Northey and McNally started the 2015 Aviva Tour of Britain on board the new Genesis Zero Z.i. This is one of three bikes in the new range (the others being the Z.2 and Z.1). The frameset is the same throughout the range and can be bought by itself in one of two colours (raw carbon/black or traditional team colours).

We reviewed the first iteration of the Zero earlier this year (Genesis Zero Team review) and its racing credentials impressed in what is a crowded market place at a pricing point peaking at £3k. It was both smooth and comfortable on longer rides but racey enough to hold its own in the pro peloton.

So what has changed? If you thought "marginal gains" were so 2012, then you would be wrong according to Genesis. Focusing on the frame, from the outside it doesn't appear to be different, but the carbon quality has been improved to a 'higher grade 30/40-ton high-modulus uni-directional' spec (try saying that ten times with stopping). In layman's terms this means 120g saving versus the previous edition (bringing a medium frame down to 960g); but, claim Genesis, 'Remain[ing] robust and durable'. 

Small amendments continue on the fork, which are more visually noticeable. Being slimmer and tapered gives a more aero profile and shaves further 90g in weight saving. Anyone looking to grab this year's forks to combine with last year's model will be pleased to hear that the same crown profile remains in place enabling retro-fitting.

The Zi comes with Dura-Ace Di2 and  carbon Vibe components from PRO, which is a welcome move.

Is it likely that those spectators lining the northern Welsh roads will notice these changes as Madison-Genesis fly by? Assuming that anyone in Wales is really bothered about any sport other than football at the moment, given Mr Bale and his band of merry men's historic rise up the FIFA rankings, unlikely. But some of these small adjustments may be just what is required to make the Zero stand out from the tradition names in the peloton.

Pricing: 

Zero Z.i: £2,999.99

Zero Z.2: £2,099.99

Zero Z.1: £1,799.99

Zero frameset: £1,099.99

Contact: www.genesisbikes.co.uk 

Look has launched a new entry-level model and has named it the 765, to avoid all confusion with the outgoing 566, which will sit alongside the 675, the 795 and the 695. Simple. We met up with the UK distributors for a first ride of a few of the key models and an in-depth look at the rest of the range.

Look 765

The 765 is the new entry level model and it replaces the 566. The 566 was considered a pretty good bike at the time, but Look admitted that it was a difficult sell as the cheapest model was £2200. The new 765 starts at a cheaper price point (just £1795 for the 105 equipped model) and has a frame weight of 1,100g.

The frame design benefits from trickle down technology from the 675 and has asymmetric chainstays and a PF30 bottom bracket for increased stiffness. However comfort is the main aim of the bike is comfort so the geometry is quite relaxed due to the short top tube and long headtube. Look is also raving about their ‘carboflax’ technology.

Carboflax is essentially a layer of linen fibre that is combined with the carbon fibre in certain areas of the bike with the intention of soaking up extra road vibration and reducing fatigue. It’s placed in the fork blades and the chainstays where Look claims it is best suited to dissipating vibration.

We went for a very quick spin on it and found the bike comfortable, but stiff enough that it’s got something going on when you get out of the saddle – like a good road bike should be then. We’ve got one in for review, so look out for something considerably more in a few weeks.

Look 675 Light 

Why look didn’t just name the aero models ‘7XX’ and the standard models ‘6XX’ is beyond me, as the 675 Light is basically a cheaper and less ‘racey’ version of the 795. We rode the Ultegra model, which retails for £2,999, although it had been fitted with Mavic Cosmic Pro Carbon Exaliths.

The only real change to range is a rejig of the finishing kit, and the dropping of the standard 675 in favour of just the 675 Light – the only difference being a higher quality carbon used to deliver a lighter and stiffer frame.

Look say that the reaction to the 675 has been overwhelmingly positive considering its rather distinctive looks although some people are a little apprehensive about the stem. The stem is specific to the frame but it can be adjusted for height (and flipped) and Look was keen to point out that people can choose whatever length stem they want as part of the price.

Our big worry when before we rode the bike was that it would have a really long reach, but it’s just an optical illusion; the 53cm frame we rode felt the same as any other 53cm bike. The front end is very direct thanks to the tapered steerer but it wasn’t particularly ‘vibey’. Once the 675 was up to speed it held it well although that was probably due to the aero Mavic wheels that were fitted. There’s a full review of the stock 675 in the latest issue of BikesEtc, available in shops from September 9^th.

Look 795 Aerolight

The Look 795 is currently available in two versions: the 795 Light, which comes with standard brakes, and the 795 Aerolight, which has integrated brakes and is the one we had with us. The integrated brake in the fork, the Aerobrake2, is a pair of carbon v-brakes and it’s a Shimano Dura Ace direct mount unit under the bottom bracket.

The 2016 model has a few updates including the new ZED3 crank and a revised cockpit. The ZED3 retains all the stiffness and weight characteristics of it’s predecessor, the ZED2, plus the trilobe crank length adjustment technology whilst also bring a smoother aerodynamic profile.

The aerodynamic upgrades don’t end there – the new aero handlebars are fitted to an adjustable aero stem, the cables are fully integrated through a plastic collars in the headtube to bypass the bearings.

How does all this affect the ride? Well on our incredibly short test run the 795 Aerolight felt seriously fast. We got up to 40kph without too much strain and it wasn’t particularly difficult sustaining it but a longer ride would be needed to see if that stiffness ruins the comfort. And the price? The frameset is £4299 with UK pricing on the builds yet to be confirmed.

Contact: Lookcycle.com

Cyclist: How did you get started at Trek?

Jim Colegrove: In 1990 Trek wanted to build composite parts in-house after a disastrous start using a separate company to build the 5000 frame. That was a made-in-one-piece back in 1988 and 1989. Terrible failure – we got virtually every one back. Key people realised carbon fibre was the future, and I was hired to help bring the manufacturing into this facility. I came from a small engineering firm in Salt Lake City that worked with aerospace clients – Boeing, Lockheed, Northrop, those kind of companies. Jackson Street was where Trek started, which was a red barn in downtown Waterloo [Wisconsin]. Trek started brazing frames there in 1976. Now it houses the CNC tool machining facility to cut all the moulds we use to make our parts. 

Cyc: Do the aerospace and military industries use much higher-quality carbon than is used in bikes?

JC: The material that the aerospace and defence industries use is nearly identical to the material that the recreational industries use. What is generally missing is certification and also verification of manufacture. We use a lot of different fibres, some of which are the same as those used for top-end military and aerospace purposes. M60J, for instance, is an ultra high-modulus Toray fibre. The last time I looked, it was something north of $900 a pound [approx £1,270 per kilo]. Some of these high and ultra-high modulus materials are classified as strategic materials, and that means they are only available in certain NATO countries because you can make weapons out of them. We use almost all the fibres out there, whether it’s Toray, Mitsubishi, Hexcel, Cytec. You name it, we’re using it. 

Cyc: What’s special about the way Trek does things?

JC: One of the key things is how we mistake-proof the process. Any time you put a human into the mix there is the possibility for mistakes. All of our products over the last five or six years have gone through our validation lab, which is a sort of mock factory. We bring in our documentation specialists who tell our operators what they’re going to do. We bring those operators into the validation lab and train them so we have a seamless transition. We try to develop things in a way that will transition well into production. Because when you take things out of a lab environment and into production there are always small glitches – things you didn’t think about.

Cyc: How do you juggle the demands of design and research in the United States while doing a great deal of your production in the Far East?

JC: What I think is really key is that what is learned here is propagated over to our Asian partners. One of the things I feel sets us apart is the fact that we are deeply embedded in manufacturing. We build all top-end Project One bikes in Wisconsin, and we know the factory is expensive, but if we don’t do it here we lose that direct connection to building the product. We can design a beautiful frame and ship it over to somebody but we’d have no idea if what we have designed is buildable and if it is buildable in a good, unique way.

Cyc: How does the composite nature of carbon fibre influence frame design?

JC: There’s sort of a ‘black aluminium’ theory where designers treat carbon as if it were a regular isotropic metal. So, some of the FEA [Finite Element Analysis] used in bike design is done by inputting aluminium as the material and designing the tubes purely on the effect of certain wall thickness. That’s not true composite FEA. That’s fine for getting an acceptable product, but if we want to dial in the type of ride performance that we’re chasing at the top, we need to do things properly. In our design you can see the number of plies and where we’ve placed them, and all of that is driven by our analysis.

Cyc: How has the trend for improved aerodynamics affected the way you approach design?

JC: Aerodynamics has really caused a dilemma for us. Aero tube shapes tend to require larger surface areas, and whenever you add more surface area to any part there’s more weight, right? Also, either it’s so harsh on the rider because it’s such a tall section, or it’s so narrow that the bike is all over the place [because of lateral flex]. That’s where our analysis really comes into play. First of all we analyse the shape from an aerodynamic standpoint, and then once we know that we have a certain aerodynamic shape, then we start plugging that into FEA. If those two aren’t going to play together then we have to add material to meet the aerodynamics, but then the bike is going to be too heavy – that’s not going to be acceptable. So we constantly converge on the best solution.

Cyc: Carbon fibre bikes are half carbon fibres and half resin. How important is the resin?

JC: Very. We don’t talk a lot about it, but we are constantly working with different resins. It’s a composite material – carbon fibre does the work and the epoxy resin holds the fibres in position. So if the resin isn’t doing its job holding the fibres in position, you’re not going to get any real performance out of the fibres. We formed a stronger relationship with [carbon fibre producer] Hexcel because it has a wide range of resins that have unique and special properties. The problem is it further complicates an already complicated concept. There is so much jargon floating around – is it a T700 or a T800 or an IM7 or an IM8, what’s the moduli, strength and elongation? It’s confusing enough without getting into resins. 

Cyc: Carbon sometimes has a bad reputation for having a limited life. Is this true?

JC: People seem concerned about carbon fibre because it’s an unknown. People have grown up with steel and aluminium. Every material has a fatigue life. Take a steel paperclip and bend it a hundred times it will probably break. Do the same with aluminium, and it will probably break in half the time because aluminium is not as good in fatigue as steel. Composites, in general, have an infinite fatigue life. But that depends on the carbon fibre use, the resin use and how well it was processed. In other words, are there a lot of voids in the laminate? Because voids will kill a composite very quickly. That was common years ago, but not any more. This, again, is where complete control of materials, process and engineering play an important role. If you take control of all of that, we can definitively say that a bike you buy today, you can ride for your lifetime, and it will not degrade over that lifetime.

Cyc: Are you on the hunt for new and extraordinary materials?

JC: We’re always looking for new material forms. Graphene is one of those, but it’s still being developed. There are manufacturers of nano-graphene platelets, so you can get it already, but it’s very expensive. The biggest thing for us is that unless we can see benefit in the composite, we’re not completely sold. If we can figure out some way of getting graphene or carbon fibre nanotubes to create the long strings like we have for current carbon fibre, oh my gosh, the stiffness, the strength, the weight would be unbelievable.

Trek.com

Scientists have been puzzling over what makes a bicycle balance since the days of ye olde penny farthing. Many experts suggested those spinning hoops make the bicycle behave like a gyroscope, but it’s not that simple. A group of engineers from Nottingham University identified 25 separate variables that affect a bicycle’s motion, citing that, ‘A simple explanation does not seem possible because the lean and steer are coupled by a combination of effects, including gyroscopic precession, lateral ground-reaction forces at the front wheel, ground contact point trailing behind the steering axis, gravity and inertial reactions…’

What is known is that as long as a bike is moving at a speed of around 14kmh (9mph), it can remain upright without the presence of a rider. But again, scientists can’t explain why. Against that backdrop, throw in the added dimension of a bend and calculating the angle that you can lean while cornering before you hit the tarmac is clearly a complex affair. In the right conditions it’s possible to see angles of 45°, but how do we get to that point?

‘We know there are three real forces acting on the bike and rider,’ says Rhett Allain, keen cyclist and associate professor of physics at Southeastern Louisiana University in the US. ‘There’s the gravitational force pushing the bike and rider down; there’s the road pushing up, which we call “normal” force, and there’s a frictional force pushing the bike towards the centre of the circular path that it’s moving in.’ 

The fake force

There’s also centrifugal force. ‘This does have an impact but it’s a fake force,’ says Allain. Many physicists argue that centrifugal force doesn’t exist and is simply a lack of centripetal force – an inward-pulling force that ensures the bike moves in a circle similar to gravity pulling inward on a satellite to keep it in orbit. It’s calculated via the equation F = mv²/r, where F is the centripetal force (Newtons), m is mass of bike and rider (kg), v is velocity (m/s) and r is the radius of the corner in metres.

‘The physics of riding a turn is that you do it by accelerating radially inwards, which is down to centripetal force,’ says David Wilson, emeritus professor of engineering at Massachusetts Institute of Technology. ‘The force has to come from the tyres. The bike has to lean so that the combination of the reaction from the tyre and the radial force is in line with the resulting force of the bike plus rider.’

Also key to how far you can lean is the coefficient of friction, which is the ratio of the force of friction between two bodies and the force applied on them – in this case the tyre and tarmac. Most dry materials have friction values between 0.3 and 0.6, whereas rubber in contact with tarmac can produce a figure of between one and two. When the surfaces are moving relative to each other – as per cycling – this figure decreases slightly.

For the bike to remain upright, the side force (centripetal) must equal the coefficient of friction, and this figure can be surprisingly large. For instance, a 70kg rider on a 10kg bike speeding at 20mph around a curve with a radius of 20m experiences a centripetal force of 316 Newtons. This force has to be generated by the tyres, and if the force didn’t exist, the bike and rider would simply carry on in a straight line.

Using some impressive trigonometric calculations that would fill a whole book, the coefficient of friction is equal to the tangent function of the maximum lean angle. ‘The wheel will slip when the coefficient of friction is exceeded,’ says Marco Arkesteijn, lecturer in sport science at Aberystwyth University. ‘This can be due to friction force increasing [due to tightening the line through a corner for example] or normal force decreasing [due to, say, a depression in the road].’

The coefficient of friction can also change due to a change in surface. That’s why cornering on a white line can be perilous. ‘This is especially true in the wet,’ says Arkesteijn. ‘Paint is less porous so the water doesn’t disperse.’ 

Rider weight

To complicate matters further is the issue of rider weight. ‘Physics-wise, smaller guys should be able to lean more,’ says Arkesteijn. ‘They’re also usually more agile, which helps.’

Allain is not quite as definite, suggesting that while rider weight matters a ‘little bit’, of greater importance is the rider-plus-bike’s centre of mass. ‘Ultimately, that’s the most important factor,’ he says. Heavier riders tend to be taller riders, especially in the pro peloton, meaning their frame sizes are larger and their centre of mass is higher. You also need to factor in road conditions. If you’re at the limit, a bump in the road can lead to a loss of traction and a fall. UK roads are sometimes grippier than those of our mainland European cousins because they’re more porous to absorb rain and prevent a slippery surface. That’s why our roads are coarser. But they’re often bumpier and in worse condition because of frost damage, hence why cycling and driving in France is an absolute joy when it’s dry.

After all that, what is the maximum lean angle? For mechanical and engineering professor Jim Papadopoulos, that can’t be answered until you throw in one final factor – trail. This is an imaginary line that’s projected down the steerer tube to the ground. If this point is in front of the wheel contact point with the ground, it’s deemed ‘positive’ and is more stable. Behind and the bike is more likely to tip over. Trail reduces the more you lean.

‘Cyclists tend to stay in the positive trail region and don’t exceed 45° of lean,’ he says. ‘It’s usually less, though when the turn is greater than 5m radius, you can reach 45°. That’s because trail becomes less of an issue – then we return to the issue of traction.’

So 45° is possible on a fast, wide, well-surfaced turn, but with so many variables at play, there is, unfortunately, no definitive answer. How far you can lean is a case of trial and (hopefully not too painful) error.