Selle Italia SP-01 Boost Tekno Superflow saddle

The Selle Italia SP-01 Boost Tekno Superflow is the ultimate statement saddle. Engineered in partnership with an F1 constructor, it is a carbon fibre chassis for your sit bones that's jaw-droppingly expensive, breathtakingly light, beautifully finished and actually surprisingly comfortable.

It looks a million dollars and certainly the SP-01 Boost Tekno Superflow could be the most expensive saddle we've ever seen. Costing £439.99, its weight of 119g makes it £3.70 a gram. Not only is it gloriously expensive but Selle Italia also claims it is "the most futuristic full carbon saddle of all time." Teaming up with Dallara, an Italian company that makes composite products for F1 cars, the saddle features Suspension Link Movement technology for a more comfortable ride and a ridiculously low weight.

I fitted it to my made-to-measure Racer Rosa and gazed at it, smitten. Then I climbed on and to my huge disappointment its gorgeously swoopy shape didn't quite fit my sit bones. With no padding at all, there's no margin for error and at lower speeds where there's more pressure on the saddle than on the pedals I could feel the carbon contours in slightly the wrong place, even through my favourite Assos S7 pad.

The hammocked shape with a pronounced kick upwards at the rear tends to decide the position of your sit bones for you and it wasn't quite where bike fitter Giuseppe Giannecchini at Racer Rosa had decreed mine should be. I felt like the Princess and the Pea crossed with one of the ugly sisters trying to force her foot into Cinderella's slipper.

However, I was overjoyed to discover that when pedalling harder, particularly at higher speeds in the drops in a big gear, which pushes you further backwards and rotates your pelvis forwards, my sit bones felt correctly placed and the innovative carbon spring suspension system took over, absorbing bigger bumps much better than it does smaller vibrations. There might be a fairytale ending after all. I am also confident that a new bike fit could place me in a position where the SP-01 felt perfect for a higher percentage of the ride time.

When I reviewed the Selle Italia SLR Boost Superflow I said the shorter 'Boost' length made it less compliant than the full-length SLR. The SP-01 system gets around this issue perfectly. Because the carbon rear is designed to flex independently, it has a measurable amount of travel built in and is much easier on the rear end, particularly at speed.

The SP-01 design consists of two rear sections which are separate from each other. What Selle Italia says is the "extraordinary level of comfort" offered by the saddle comes from the movement of the two sections, which are designed to operate like independent suspension with the movement of the hips, allowing greater freedom of pedalling, lateral flexion and shock absorption.

As Mat noted when he reviewed the Selle Italia SP-01 Boost Kit Carbonio Superflow, you don't actually feel the two halves moving independently – it's more subtle than that. Possibly the only thing about the SP-01 Boost Tekno Superflow that can be described as subtle.

'Superflow' describes the dramatic cutout designed to reduce perineal numbness. This, along with the Boost shorter length, makes riding in the drops much more comfortable for a high pelvic rotator with an inflexible back like me.

The split shell design definitely divided opinion when I posted a photo of it on Strava. It was loved and hated in equal measure (though you have to wonder if the haters were just jealous). There's no question that the radical shape with the carbon weave looks incredibly bling but, as was also pointed out, you don't get much saddle for your money – which is, of course, the whole point.

Selle Italia gives the SP-01 Boost Tekno Superflow five stars for 'medio fondo', two for 'granfondo' and none for endurance or cycle touring, by its own admission suggesting it's not a saddle for huge mileage, and I'd go along with that. It's a racing saddle designed for short, sharp efforts and works best when you're going fast and pedalling hard for up to three hours.

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Obviously, for someone building an ultimate, no-expense-spared hill-climb bike it would be perfect whether it fitted your sit bones or not, since you wouldn't actually be sitting on it!

Value and conclusion

There's really nothing to compare it to in terms of value and we've never reviewed a saddle at road.cc that has broken the £400 barrier. Fizik's Arione 00 Versus Evo is £325 and 167g; the SP-01 Boost Kit Carbonio Superflow Mat tested is £250 and 170g.

The Selle Italia SP-01 Boost Tekno Superflow is a money-no-object dream saddle that was possibly designed more as a showpiece than for slogging round the lanes. If you are one of the world's best known racing saddle manufacturers you've got to have something pretty special at the top of your range that showcases your expertise in materials science and engineering – regardless of how many you sell – and this extraordinary saddle most definitely does that.

Verdict

The ultimate concept saddle showcasing all of Selle Italia's expertise, with a price that's off the scale – sex on rails