Ibis Cycles Silk Carbon Frame

Frame

We began by asking Nicol to outline some of the features Ibis have incorporated into the design, and he told us they use a blend of several grades of fibres, but mainly the popular Torayca T700 that Nicol believes is the best available in terms of overall performance.

"Our goal was to mate the responsiveness of a large tube aluminium bike with the suppleness of a Ti bike," he told us. It is used here, together with a higher modulus carbon in areas that require the most stiffness, such as the bottom bracket. Nicol added, "It can survive a 900lb frontal impact at the front axle before failure of the down-tube occurs - greater than many full suspension mountain bikes - and the dropouts are compression-moulded carbon for lightness."

There are five frame sizes, ranging from 50-61cm, based on the dimension from the centre of the bottom bracket to the top of the seat tube. The 56cm top-tube and 98.5cm wheelbase of the size 55cm bike correspond with a generic medium size perfectly; the next size up has a 57.4cm top-tube.

The relatively stretched and low riding position is clearly intended for the serious club racer. While the head-tube is not as short as on the perfect time trialling machine, the Trek Madone, the 55cm Silk Carbon is perfect for a rider of around 6ft with clip-on tribars attached to effect a low riding position for time trialling.

The finishing layer of coarse carbon fibres has been applied so neatly it is nothing short of a work of art, and the down-tube decal is an exercise in tasteful understatement.

Equipment

On our test bike, the Thomson stem was very effective in resisting the twisting forces exerted by the rider in a sprint, and the Easton EA70 handlebars have a gentle anatomic bend that is a favourite in the Cycling Plus office. The padding of the Selle Italia XC-R SLR saddle is minimal but provides good support to the sit bones when riding hard. Slightly built riders like me, though, will feel the effects of vibrations on longer rides, so for those occasions we recommend a good pair of shorts and that you fit a Fizik Arione saddle.

Wheels

Stif Cycles specify the ā300 Easton Vista wheels on their Ultegraspecced complete bike package, but the owner of our test bike opted for Dura-Ace wheels. The general consensus around the office is that these look good and complement the simple and understated graphics of the frame.

In performance terms, they register about halfway along the stiffness scale - if you want stiffer wheels, source the Fulcrum R1s, and if you want a lighter and more comfort-inducing ride, we advise going for the Easton Vista SLs.

The Vittoria Open CX clincher tyres are an old-time favourite. The larger-than-average air space makes the bike feel very reassuring over poorly surfaced roads, and on fine tarmac they hum gently just like a fine tubular on a team issue level bike.

Handling

The Silk Carbon might be a little too stiff for some tastes, although we know that a lot of professional riders look for this character in a bike; it certainly heightens your perception of speed while competing. We liken the ride character to the Isaac Sonic - the stiffest bike we've ridden - but, like the Sonic, the Silk is a curate's egg to most riders: good in parts. On the one hand it has exemplary stability when cranked hard into a corner, but on the other, it amplifies every nuance of the road surface and demands your full attention, especially when you've been riding for more than 50 miles on poor road surfaces and your hands have gone numb.

On fast descents, the Ibis's excellent lateral stiffness gives a very direct response to turning, and we would recommend the Silk without hesitation to the rider who enjoys pushing the limits of their handling skills on fast descents, with the Vittoria tyres having seemingly unlimited reserves of grip on smooth, dry surfaces.

With several long rides under our belts, it is clear that the stiff and unyielding character and low-slung riding position of the Silk Carbon is best suited to elite level roadies, rather than the long distance sportive rider for whom comfort is a priority.