Ribble Cycles has launched a new Ultra aero road bike with a radical frameset design, an innovative handlebar, and some bold aero claims.
Dubbed the Bat Bike during development, Ribble says that the Ultra’s design brief was to be “the fastest aero road bike in the real world” – in other words, the fastest with a rider in place as opposed to one that performs well in the wind tunnel with no one aboard.
“We always test bike and rider because the interaction from an aerodynamic perspective is vital,” said Ribble’s CEO Andy Smallwood. “How the airflows over the bike and hits the rider is crucial.”
With that in mind, it took a digital scan of a test rider to use throughout the CFD (computational fluid dynamics) process and used the same test rider in wind tunnel testing, and then in the real world. It also used other riders – both male and female – in the wind tunnel, plus a mannequin.
“As we progressed through the project it became very evident that the aerodynamics of the bike have a significant positive or negative impact on the rider, particularly on elements of the bike that are directly downstream of the rider,” says Ribble. “Through this analysis, we examined in minute detail how the airflow from specific areas of the bike can be manipulated upstream (in front of the rider) to maximise their positive aerodynamic impact on the rider downstream.
As usual with aero bikes and components, the initial work was done on computer using CFD software.
“CFD (computational fluid dynamics) allowed the team to understand the aerodynamic challenges and how to use the design to maximise and manipulate the airflow to generate a significant performance gain across a full range of yaw angles from 0° (head-on) to an extreme 20° and speeds from a pro rider’s 29mph and the more average road cyclist speed of 22mph. We were very keen to develop a bike not only for the pro but for the everyday cyclist,” says Andy Smallwood.
Yaw can be understood as the apparent wind that results from the speed and direction of the bike/rider and the speed and direction of the wind. Ribble says that it included a negative sweep (measuring the aerodynamic performance on the opposite side of the bike) when required and it optimised the performance for yaws between 5° and 10° because that’s what you’ll encounter most of the time in the real world (Ribble says that 5-7° is what you’ll get on a typical day, up to 10° on a windy day).
Ribble says that every section of the frame, fork, seatpost and handlebar has been aerodynamically optimised with particular attention paid to the integration of components.
“When the shape and initial component material layup had been defined, extensive and detailed wind tunnel testing was employed to test and qualify the gains seen at CFD level,” says Ribble.
“The wind tunnel results [Ribble used the cycling wind tunnel at Silverstone] are extraordinary and illustrate the importance of considering the total package of bike and rider to obtain the best aerodynamic efficiencies.”
We’ll have more on those results later.
Frame and fork
Many truncated aerofoil tube profiles feature on the Ultra frameset – essentially, airfoils with the tails removed, as you’ll find on aero road bikes and time trial bikes from other brands.
“A conventional airfoil is great in a straight line but as soon as you move off to yaw the air detaches pretty quickly,” says Andy Smallwood. “We know that truncating it helps a lot but rather than stopping there, we really looked at the tube profile in detail. We started looking at the chord – the widest part of the profile – nudging it backwards and forwards to get to an optimum position which is the ideal location across a yaw sweep.
“We also looked at the truncated trailing edge, making it wider and making it thinner. Then we amalgamated the work on the chord and the work on the truncated edge together to get to the finished tube shape.
“One particular tube profile might be fast up to 10° yaw, but if the air detaches suddenly at that point it could lead to instability in crosswinds so you might go for a slightly slower profile with greater stability and more consistency across the full yaw sweep. We went through this process for every section of the bike.”
The lower section of the down tube, for example, has been optimised for use with a standard water bottle in place and Ribble says that a straight-edged aerofoil proved most beneficial in terms of reducing drag from 5° of yaw upwards.
“The best design we achieved is a truncated airfoil with very flat sides, utilising the bottle shape to finish off the airfoil,” says Andy Smallwood.
Ribble says that the Ultra Road is faster with the water bottle in place than without and that the profile of the lower down tube generates thrust at +10° yaw.
The profile of the head tube has been extended with a long trailing edge that is said to improve aerodynamics at higher yaws while remaining within UCI regulations.
Concerning the fork, Andy Smallwood says, “There’s a gain to be had by moving fork blades in front of the rider’s legs, which is something that Team GB have done with their Hope track bike.
“When the air is head-on, we saw exactly what Team GB saw. Move the blades outboard and you get a wake behind the fork which is a benefit. On the track that’s absolutely fine because you’re working to low parameters of yaw, but it’s different when you’re riding outside. By 2.5° yaw, we’d lost the benefit completely, and the results then went off in a negative direction. The best solution was for the fork legs to go straight up vertically from the dropouts and go in right at the top.”
In terms of dimensions, Ribble says that an 80mm deep fork was most aerodynamically efficient up to 10° yaw but there was a big drop off beyond that point. A blade 68mm deep and 15mm wide proved to be the clear winner across the full range of yaw and actually started to generate thrust from 5°, according to Ribble.
“On the non-driveside, we’ve enclosed the disc brake calliper behind the fork blade so there’s nice clean airflow there rather than extra drag,” says Andy Smallwood. “We’ve also positioned the seatstays directly behind the fork blades so that they sit in the wake.”
Ultra bar design
One of the most eye-catching features of the new bike is the Ultra combined handlebar and stem.
“We know that the handlebar is one of the most important elements of the bike because it makes contact with the rider and it is directly upstream of the rider – in terms of aerodynamics, it has a big impact on the rider behind it,” says Andy Smallwood.
“When we first looked at it we thought that the only elements we could alter were the wing sections and the stem. The drop and the section where the lever goes are out of bounds because you need a round section of tube for the band that holds the lever in place. If we could get rid of the necessity for that band we could shape the handlebar however we liked.”
Ribble came up with a system where the dual-control lever bolts directly to the Ultra bar, eliminating the need to use that band.
“The lever is positioned in the conventional location and attached to the handlebar using a removable and adjustable plate,” says Ribble. “The plate is accessible via a cavity at the rear of the bar and allows the lever to be adjusted through the horizontal and vertical planes.”
You get 15° of side to side movement and just under 30mm of vertical movement.
Ribble says that ditching the band has given it greater freedom, allowing it to shape the drop section and the transition between the tops and the drops for aerodynamic and ergonomic benefits.
Another key feature of the Ultra bar is the bulge on the top section. What’s the reasoning there?
“Think about whether you’d be better off riding behind a super-aero Ferrari or a van in terms of aerodynamics,” says Andy Smallwood. “You’d rather ride in the wake behind the van so we thought, can we design a handlebar that’ll shed a wake on the rider’s legs? That’s what we’ve done here.”
In short, the bulge is designed to be a wake generator that creates a drag reduction zone for the rider to sit in.
“Initial tests of the bars without the wake generators produced significant aerodynamic benefits versus a standard bar but these were negated by the airflow impacting the rider’s legs,” says Ribble. "The wake generators provide further measurable aerodynamic benefits across a full range of yaw and multiple hand positions when compared to standard handlebars and the new bar without wake generators. This is due to the wake generators’ ability to manipulate airflow upstream of the rider.”
The bars are narrow too, and this provides further aero gains.
“We’ve gone with various stem lengths but the maximum width is 38cm to the hood, 40.5cm at the curve of the drop, and 42cm at the ends,” says Andy Smallwood. “The thinking there is that this is an aero bike and you don’t just get the benefit from the bike itself but through the fact that we’re promoting an aerodynamic ride position too”
One more interesting feature of the handlebar is that it’s designed to be used without tape.
“Bar tape is not that great in terms of aerodynamics and it’s a faff, so we’ve given the bar a textured finish,” says Andy Smallwood, “Because it’s carbon, you have enough vibration damping without the need for tape.”
Ribble has applied for patents for the method of directly mounting the dual-control levers, the wake generators, and the non-round drops.
Aero gains
Ribble has measured the Ultra against its existing Endurance SL R aero road bike throughout the development process. It doesn’t offer statistics for the aero performance of its new bike compared with models from other brands but says it has great confidence in its design and data.
As mentioned up top, Ribble tested in the wind tunnel at two different speeds: 22mph and 29mph.
Comparing the Ribble Ultra and the Ribble Endurance, each with a rider on board and fitted with Ribble’s existing Level handlebar rather than the new Ultra bar – so you’re looking at the benefit of the frame, fork and seatpost – Ribble claims a 54.9-second advantage over 40km (25 miles), averaging 5° and 10° yaw for the Ultra at 22mph, and a 50.25-second advantage at 29mph (obviously, any bike moving at 22mph will cover 40km in exactly the same time as any other bike moving at 22mph; bike brands calculate the wattage saved at a particular speed and convert that to a time saving).
The shorter amount of time saved at the higher speed is because although the aero benefit is greater, this is outweighed by the fact that you’re on the course for less time.
Ribble says that adding the Ultra’s new handlebar saves more time. Averaging 5° and 10° yaw over 40km (25 miles), you’re looking at a saving of 75.05 seconds over the Ribble Endurance with a Level handlebar at 22mph. The Ultra’s advantage at 29mph is 61.4 seconds (obviously, the point made above about the time savings of bikes moving at particular speeds applies here too).
Ribble says that the new bar was always tested on a like for like width basis versus the Level 5 bar to ensure consistency and that the narrowness of the Ultra bar will provide additional aero gains.
The more affordable Ribble Ultra SL, made with a lower grade of carbon than the Ultra SL R and without the Ultra handlebar, is a claimed 54.9 seconds quicker than the Endurance SL R over 40km (25 miles) at 22mph (averaging 5° and 10° yaw), and 50.2 seconds quicker over 40km (25 miles) at 29mph.
When tested in a bike-only scenario the Ultra SL R (with the new Ultra bar) is outperformed by the Ultra SL (without the Ultra bar), according to Ribble. However, with a rider in place, the Ultra SL R is said to be 20.5 seconds quicker than the Ultra SL over 40km (25 miles) at 22mph (averaging 5° and 10° yaw) and 11.4 seconds quicker over 40km (25 miles) at 29mph.
Models
The Ultra Road is available in two models: Ultra SL R and Ultra SL.
The Ultra SL R’s frame (size medium) weighs a claimed 1,050g while the SL version is 250-300g heavier. The Ultra handlebar/stem is a claimed 450g. Ultra SL R complete bike weights are from a claimed 7.6kg (based on a medium frame).
A Ribble Ultra SL in a Shimano 105 build is £3,199.
A Ribble SL R in a Shimano Ultegra build is £4,299.
Many other builds are available and customisation is possible through Ribble’s online Bike Builder tool which allows you to select the components you want from a large range of options. You can also select your own finish using Ribble’s Custom Colour program.
One interesting option is the triathlon-specific Ribble Ultra SL R with a clip-on aero bar and tri-spoke wheels. It comes fitted with a Shimano Ultegra Di2 groupset and costs £6,599.
The Ultra SL R is also available as a frameset for £2,999
www.ribblecycles.co.uk
Add new comment
34 comments
Ribble do seem to be churning out new models at a rate of knots these days. As discussed elsewhere, they might be better off sorting out their supply chains/customer services to deliver the bikes they already make/have sold!
I live down the road from Ribble, many people in the area would not have a Ribble bike, they have a horrendous reputation, just Google Ribble Cycles and read the reviews for yourself. Before launching new models, they should put their efforts into delivering the 5000 plus bikes customers have ordered, and paid in full for.
If you read the reviews on, eg Trustpilot, you'll see a combination of 5 star and 1 star reviews and not much in between. Having finally got my bike, I'm very happy with it. But I agree with your final sentence; that was my point.
I took delivery of a Ribble frameset this week. Arrived on time, just with the wrong fork, wrong seatpost clamp, and missing a thru axle.
Lovely looking bike, but every new bike is so expensive these days. Dreading having to buy my next one.
Why do companies insist (and why do Road.cc repeat it?) on making impossible claims? It is impossible for an object travel at a set speed over a set distance and get there on a shorter time than another object doing the same distance at the same speed.
That's always amused me too.
I assume that they mean 'at wattage X this bike is Y seconds faster over distance Z'.
Or alternatively 'this bike requires wattage X to produce speed Y'
Nothing impossible, the claim is consistent. Speed is given to two significant figures, so about a minute of difference over 40km would not make a difference to that average speed. The point is you have to be travelling around 37km/h or 48km/h over 40km to see those differences. Someone travelling at 48km an hour would get there long before me whatever the bike.
Isn't that addressed in the parenthesis:
(obviously, any bike moving at 22mph will cover 40km in exactly the same time as any other bike moving at 22mph; bike brands calculate the wattage saved at a particular speed and convert that to a time saving)
Yes, your are correct. My shaking fist of annoyance must have got in the way of seeing that Road.cc had dealt with that.
It's still an impossible claim though (apart from due to rounding, as Drinfinity says)
Relax, you can still be furious at the mix of units. I think they mean that at 0.73 leagues per wait for a helmet debate on road.cc to get toxic, the aero bike will be e^iπ% more likely to be at the front of the café stop queue. Assuming yaw angle of less than π/6 radians, obv.
The mixing up units was also an annoyance. Back to fist waving for me
If you're thinking of buying one, don't expect to be riding it much before next May. Don't know delivery times for Orro's Venturi, which seem to be a direct UK rival, as already mentioned
"We are currently experiencing high demand..." I wonder what that actually means? Higher than the average over the last x months? Higher than this time last year? Upper quartile? One standard deviation?
Or is the truth, "we can't get the parts so we can't satisfy ordinary demand"? And, to what extent are they obliged to tell the truth in public facing consumer sales communications?
It means: dear customer, let's put some pressure on you hoping you will buy one asap, regardless of real demand.
I think others have made the point that they've taken orders and full payment for bikes they've not yet made so that could be the "high demand" they mean. So it does seem odd that they're launching a new bike that is only going to increase that demand.
Get as many orders in as you can before the build slot at the factory actually opens, thus lowering the unit cost
Interesting. At that price point, it's going squarely up against the Orro Venturi in my mind. It's a good looking thing, and the custom paint is obviously a nice (expensive) bonus.
I do worry about that handlebar though. Not because of the clever features, because it won't give much play in terms of stem/bar sizes.
The ribble is a great looking bike and I may well have gone for it over my venturi based on the aero claims alone...but it is a lot more expensive - the 105 model is £500 more than the Ultegra Venturi...and thats the cheaper Ribble version too
Judging by the ribble thread in the forum, delivery takes a very, very long time.
I think I'd still rather have a Venturi over the Ribble. When I come to buy my next bike I think it'll be a Venturi. They just look sorted from front to back now they've integrated the cables.
Are they as good as the reviews suggest?
I really like mine. I was smashing PR's (ok koms) I'd been after for years within days of getting it despite not being particularly fit or light at the moment.
Pretty comfortable too. As with Ribble, they do have supply problems though don't think it's as bad. They have some fancy colours coming for the more expensive version (which has upgraded bars and wheels). If you buy direct from Orro you can specify the bar width etc if you have a preference.
presumably it also allows them to design the interface in a way that stops the clamp from causing structural damage. yes canyon, we're thinking of you.
nice metallic chameleon paint too, looks familiar.
Looks like a much more expensive version of my Venge-alike bike.
Ilook forward to chugging past fat middle aged men decked out in brand new Rapha on these in the near future
Why?
Because lukei1 is better than them obviously!!!!!!!!!!
And he has a tiny dick (less weight/more aero)
Body shaming seems in vogue today
I can't stand comments like this. That "fat middle aged man" might be someone who's just getting to grips with cycling or could even be someone coming back from a long term illness/injury who has bought a new bike to get them motivated and back out on the road.
I can't stand comments like this
I can! Fat rich middle aged men can take some jocularity, especially if they're daft enough to waste money on an aerodynamic bike to trundle around their non-aerodynamic bodies
Pages