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BTwin Ultra 700 AF



Stunning value for money race bike that's a joy to ride, whatever your performance goals

At every product is thoroughly tested for as long as it takes to get a proper insight into how well it works. Our reviewers are experienced cyclists that we trust to be objective. While we strive to ensure that opinions expressed are backed up by facts, reviews are by their nature an informed opinion, not a definitive verdict. We don't intentionally try to break anything (except locks) but we do try to look for weak points in any design. The overall score is not just an average of the other scores: it reflects both a product's function and value – with value determined by how a product compares with items of similar spec, quality, and price.

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Often when we're reviewing bikes under a grand we highlight areas where upgrades are needed or even welcomed – but there is none of that with BTwin’s Ultra 700 AF. It's a cracker straight out of the box, offering one of the best ‘bang for buck’ options you're likely to find for 750 of your British pounds.

That's not to say the Ultra isn't upgradeable. With a stiff, performance-orientated frameset, it could easily accommodate some bling upgrades without overshadowing the main component.

> Find your nearest Decathlon store

> Buy this online here

BTwin, if you haven't heard of it before, is the in-house brand of French sports superstore company Decathlon, which concentrates on the 'value for money' ethos for many of its goods. Don't confuse value for money with cheap, though – the Ultra 700 AF is a quality piece of kit.

What’s it made of?

At its heart is a triple butted aluminium frame, which comes with a lifetime warranty, internal cable routing and direct mount brakes; pretty up to date, then, with current trends.

BTwin Ultra 700AF - full bike.jpg

Our medium Ultra 700 AF has a head tube length of 147.5mm paired with a 548mm top tube, giving a position somewhere in between that of a full race bike and a shorter, more upright so-called endurance bike.

In reality that means you can ride the BTwin at a real old lick without have to scrunch yourself up into a ball to get into an aero position. It's a quick bike too, with very impressive stiffness for an entry-level alloy frame.

BTwin Ultra AF 700 - riding 2.jpg

BTwin hasn't gone down the route of oversizing the bottom bracket junction, keeping with a standard sized press-fit unit, but the frame doesn't seem to lack anything because of it. Really stamping on the pedals on a steep climb or in full-on sprint mode will find the smallest hint of flex at the BB, but we are talking minor amounts here and not something you'll pick up on unless you're really looking for it.

BTwin Ultra 700AF - bottom bracket.jpg

BTwin has oversized the front end, though, using the now pretty standard tapered head tube – 1 1/8in at the top flaring to 1 1/4in at the bottom. It's all about adding stiffness by increasing the cross sectional area; firstly it gives you a larger weld area so you can increase the diameter of the down tube, plus the alloy steerer of the fork is bigger, with all of these tweaks allowing for better resistance to steering and braking loads.

BTwin Ultra 700AF - head tube.jpg

As a result, the handling on the Ultra AF is very direct with a positive feel to it, something it manages without being overly twitchy at the front end. The steering has a very neutral feel while still being responsive, which is ideal on a bike that's likely to be bought by those getting into the sport.

For those with a bit more experience, or riders who just like a bit of an adrenaline hit, the BTwin maintains that positivity as the speed increase. It may not have the precision of some thoroughbred race bikes but it's not going to be found wanting until you are absolutely pushing it to its limits – and for this price range it still comes up better than I was expecting.

Harsh criticism?

Comfort is often cited as a reason to avoid aluminium alloy bikes and it's true, the Ultra AF can feel a little on the harsh side at times, though it is still far from uncomfortable. It's just not as refined as some, but still manages to tame road buzz to a minimum.

Up front the Ultra Evo Vario fork uses an alloy steerer but does have carbon fibre legs, which offer more damping than an alloy version ever would.

BTwin Ultra 700AF - fork.jpg

At the back end BTwin has removed the rear brake bridge as it's not needed because of the AF using direct-mount brakes; more about that in a minute.

BTwin Ultra 700AF - seatstays.jpg

The seatstays have been slimmed down too, which promotes a bit of flex, especially as they aren't constrained by a brake bridge joining them. These are all minimal things, and you could go further by swapping to a carbon seatpost and running the 25mm tyres a bit softer – plus it looks like some 28s should fit without too much trouble.

Speedy and sedate

Adding all this up then, what do you get? Quite simply, an all-round mile muncher that's got a kick for some speed work – I can't see any reason why you couldn't race it, after all it is UCI approved. It's fun to ride when you want it to be, and sedate and easy to live with when you want to take things a little more steadily.

BTwin Ultra AF 700 - riding 3.jpg

That term 'value' constantly rears its head whichever way you look at the Ultra. Shimano's 105 11-speed groupset is rare to find on a bike at this price, and even though BTwin has cut costs a little by fitting an RS500 compact (50/34) chainset, it's still a very well-specced bike. The shifting is a little less crisp without the 105 series 5800 chainset, but you'll only notice it if you ride the two side by side.

BTwin Ultra 700AF - chainset.jpg

A nice touch is that even though our test model came with Shimano's pretty much de rigueur 11-28 tooth cassette, the bike has a long cage rear mech, which gives scope for a bigger spread of gearing to be used – a 32t large sprocket, for instance – and you'd only need to change the cassette. It's something new riders might want, so makes a lot of sense.

BTwin Ultra 700AF - rear mech.jpg

BTwin has decided to spec the Ultra with direct-mount brake callipers; these are fitted to the frame and fork directly with two bolts rather than threading a single fixing through and attaching at the rear with a nut like traditional dual pivots.

BTwin Ultra 700AF - front brake.jpg

This creates a stiffer brake body and junction between that and the bike, and offers more powerful braking for the same amount of rider input. I've used direct mounts a few times and the results have been minutely noticeable, but the Ultra AF seemed to respond very well to them, with heavy braking easily picking up the rear wheel as your body weight lunches forward.

Wheels and finishing kit

As far as the rest of the kit goes, it's all provided by BTwin. Wheels are often the first point to upgrade on bikes at this price, but again the Ultra doesn't really need that. Admittedly some lighter wheels would lower weight and increase acceleration or benefit climbing, but it's not something you need to do straight away.

BTwin Ultra 700AF - fork crown and rim.jpg

The 28mm-deep alloy rims with 20 front and 24 rear spoking patterns never feel like they are holding the bike back. They stayed true throughout testing and the bearings certainly didn't grumble after wet rides.

The 25mm Hutchinson Equinox tyres also roll well and offer decent levels of grip. Again you could upgrade, but I'd wait until these wore out first.

BTwin Ultra 700AF - tyre.jpg

The alloy seatpost, stem and handlebar are all in keeping with the Ultra AF, offering solid performance without being overly flashy. They do the job they are designed for, nothing more, nothing less. The shallow drop handlebar makes getting into and maintaining plenty of riding positions achievable for even the most inflexible of us too.

BTwin Ultra 700AF - bar drop.jpg

I really liked the BTwin saddle, too – very plush without being squidgy.

BTwin Ultra 700AF - saddle.jpg

Overall, the BTwin Ultra 700 AF is an absolute blinder of a bike, even without taking the whole value thing into account. When you ride it, it never feels like any compromises have been made to deliver the package. Okay it's a little on the weighty side according to the scales, but out on the road it never feels like that.

> Check out our guide to the best £500-£750 bikes

The Ultra is a great bike to ride, offering a really stable footprint but managing to be exciting at the same time, which means you can go out for a long, steady cruise or a short blast, whatever your level of fitness or experience, and come back with a grin on your face.

> …and some great bikes for under £1,000

I've mentioned value quite a bit but there are a couple more things to add: BTwin offers a lifetime warranty on the frame, fork, stem, handlebar and seatpost, and the bike even comes with a set of clipless pedals and cleats.


Stunning value for money race bike that's a joy to ride, whatever your performance goals

If you're thinking of buying this product using a cashback deal why not use the Top Cashback page and get some top cashback while helping to support your favourite independent cycling website test report

Make and model: BTwin Ultra 700 AF

Size tested: M

About the bike

State the frame and fork material and method of construction. List the components used to build up the bike.


Our new B'TWIN ULTRA frame is derived from the Evo Vario concept. Aluminium is an ideal choice for obtaining an excellent propulsion-to-comfort ratio. The variable thickness tubes considerably reduce the weight and ensure excellent performance on all surfaces, even very rough terrain. The design is aerodynamic, the cabling is integrated into the frame and the rear brake is positioned under the chainstays.

This frame is UCI-approved.

Weight: 1400 g in size M.


Our new B'TWIN ULTRA Evo Vario fork is mounted exclusively on the B'TWIN ULTRA Evo Vario frame. The combination of carbon and aluminium offers perfect synergy between the B'TWIN ULTRA Evo Vario frame and fork. We have achieved a damping effect on very uneven and bumpy terrain such as paving or cobblestones. Aerodynamic design with brake located as close as possible to the fork. Weight: 550 g in L .


Shimano 105 11-speed drive train.

Shimano 105 SS double, front derailleur

Shimano 11-speed rear derailleur

Shimano RS 500 chainset.

Shimano 11-speed rear derailleur.

Shimano RS 500 chainset.


Shimano RS 500 50x34 chainset.

Crank length varies according to size of bike: XS, S: 170 mm / M: 172.5 mm / L, XL: 175 mm.

SHIMANO 105 11S 11 x 28.



Shimano 105 direct mount brakes (fork and chainstay): their double pivot technology offers precision and power. Centring is always perfect with DPB technology, and they are made from cast aluminium and covered with a powder coating that withstands frequent washing.


The compact B'TWIN handlebar is scaled to the size of the bike. The compact shape is becoming increasingly common in the peleton, as it allows you to keep your hands low on the handlebars without compromising comfort. Weighs 320 g in size 420 mm. The stem is also made out of 6061-T6 aluminium. Scaled to the size of the bike. Weighs 140 g in size 110 mm. The steering uses long-life, sealed bearings, with a 1 1/8in diameter at the top and 1 1/4in at the bottom.


The wheels were developed by B'TWIN's engineering office. This pair of wheels is designed for all-terrain use, with 20 spokes at the front and 24 at the rear. The rim is 28 mm high. Very versatile profile and hubs fitted with long-life cartridge bearings.

Weight: 1.790 kg per pair.

This wheel is used by the B'TWIN U19 RACING team in training and competition.


Hutchinson Equinox 25 C for higher performance and added comfort.


B'TWIN Comp Ergo Chromo saddle: chosen for its comfort and efficiency. Weight: 257 g.

B'TWIN Competition aluminium seat post.

Diameter: Length: 31.6 mm;: 350 mm. Weight: 240 g.


B'TWIN Comp VPR76 clipless pedals (come with cleats).

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?

BTwin says: "Replaces the highly acclaimed Alur 700. Upgraded with Shimano's 11s 105 groupset & R500 crankset and 25mm tyres for 2015. This unique triple butted UCI approved racing frame with a lifetime warranty remains at it's heart with full internal cable routing, ESR ready, powerful direct mount brakes and carbon forks really sets this bike apart."

The Ultra 700 AF is more than an entry level racer; the geometry is slackened off a touch but it is still a responsive, fun bike to ride at speed.

Frame and fork

Overall rating for frame and fork

Tell us about the build quality and finish of the frame and fork?

Triple butted tubes, internal cabling, tapered head tube... there is a lot going on and it all comes together to create an excellent frameset. Although not the most refined alloy frame out there, when you consider the overall price it's hard to knock it. The paint finish is hard wearing too.

Tell us about the materials used in the frame and fork?

BTwin doesn't state the alloy grade but the use of triple butting (three differing tube wall thicknesses along its length) helps to bring down weight and add comfort.

Tell us about the geometry of the frame and fork?

The Ultra 700 AF sits somewhere between a full race bike and an endurance bike, which gives it a fast ride with positions accessible for a large range of riders.

How was the bike in terms of height and reach? How did it compare to other bikes of the same stated size?

Decathlon doesn't quote any stack and reach figures (the vertical and horizontal measurements from the centre of the bottom bracket to the top of the head tube) but with a quick tape measure the ratio comes in at around 1.45, which puts it well in the sporty yet comfortable camp.

Riding the bike

Was the bike comfortable to ride? Tell us how you felt about the ride quality.

A little harsh on rough road surfaces but not what I'd class as uncomfortable.

Did the bike feel stiff in the right places? Did any part of the bike feel too stiff or too flexible?

Yes, a tiny bit of flex around the bottom bracket, but barely noticeable.

How did the bike transfer power? Did it feel efficient?

It responds well to a hard effort.

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? Neutral and responsive, a very balanced yet fun bike to ride.

Tell us some more about the handling. How did the bike feel overall? Did it do particular things well or badly?

The Ultra 700 AF is a very solid feeling bike with really good feedback levels letting you know what the tyres are doing.

Which components had the most effect (good or bad) on the bike's comfort? would you recommend any changes?

The comfortable saddle took the sting out of rough road surfaces.

Which components had the most effect (good or bad) on the bike's stiffness? would you recommend any changes?

The wheels are stiff and the handlebar/stem combo provides a tight front end.

Which components had the most effect (good or bad) on the bike's efficiency? would you recommend any changes?

The whole bike is a competent package with no one component standing out.

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The drivetrain

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Tell us some more about the drivetrain. Anything you particularly did or didn't like? Any components which didn't work well together?

Shimano 105 is brilliant, and although you don't get the 5800 chainset you do get the excellent direct mount Shimano brakes.

Wheels and tyres

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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?

For an own brand set of wheels the BTwin's are hard to fault. Light enough to provide a spirited ride without sacrificing reliability. The frame does suit deeper section wheels if you are considering an upgrade.

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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?

For budget tyres with a minimal TPI count they are actually very responsive and offer great rolling resistance.


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Tell us some more about the controls. Any particularly good or bad components? How would the controls work for larger or smaller riders?

The BTwin stuff is simple but offers decent performance for the money.

Your summary

Did you enjoy riding the bike? Yes

Would you consider buying the bike? Yes

Would you recommend the bike to a friend? Yes

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Use this box to explain your score

A solid scoring round from the Ultra 700 AF which highlights just how 'very good' it is, but when you take the value into account things step up a league. At £1250 you'd go, "hmmm, impressive", but at £750 you're thinking, "that's bloody amazing!"

Overall rating: 9/10

About the tester

Age: 37  Height: 180cm  Weight: 76kg

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 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!

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