Ribble says it set out to “make the most aerodynamically advanced frameset in the world” and to do this, it invested three years of intensive CFD (Computational Fluid Dynamics), wind-tunnel testing and real-world development.

The Ultra SL uses a Toray T800 / T1000 carbon frame, which is identical in shape to the Ultra SL R frame but sees less use of the more premium T1000 fibres to hit a lower price point. Ribble says this carbon layup “offers a blend of low overall weight and high stiffness, while incorporating ride-dampening compliance”. It quotes a 1,200g frame weight for a painted size medium.

The aerofoil tubes are deep and truncated throughout, the down tube flaring out dramatically at the bottle cage location. The narrow head tube is also designed to reduce the frontal area.

The seatstays are particularly interesting in that they are dropped but offset slightly and give the bike a distinct aesthetic when viewed from behind.

Ribble says the frame is aerodynamically optimised around 700c x 28mm road bike tyres, but has clearance for tyres up to 32mm.

Many will doubtless be pleased to hear the Ultra foregoes a press-fit bottom bracket and is instead specced with a BSA threaded bottom bracket.

The fork is also striking, with a 68mm blade depth, found to be more aerodynamic overall than the 80mm blades the brand also tested in development. It’s constructed from a mixture of Toray T700 and T800 carbon fibres.

The aero seatpost is also proprietary, with its wide profile in keeping with the shape of the seat tube.

Kaden Gardener / Our Media

Although the radical Ultra Bar doesn’t find its way onto this model, Ribble specs its own Level 5 Carbon Integrated bar-stem, which hides any cables or hydraulic hoses neatly.

Our size-large test bike is specced with a 42cm bar width and 110mm stem length, but this can be customised at the point of purchase via Ribble’s online BikeBuilder tool.

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This is our chance to introduce the bike and everything that makes it unique before hitting the road or trails.

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A 105 Di2 spec

Kaden Gardener / Our Media

Our test bike is the Ultra SL Enthusiast, which retails for £4,099 / $4,190.35 / €3,973.53. European prices exclude VAT and may be subject to import taxes.

It sits in the middle of the SL range. There are more affordable models, with a Shimano Ultegra R8020 build for £3,899 / $3,985.89 / €3,779.65, and a Shimano 105 R7020 equipped bike for £3,499 / $3,576.98 / €3,391.90.

There are also more expensive builds in the range with SRAM Rival eTap AXS and Shimano Ultegra Di2, rising to £4,599 / $4,701.49 / €4,458.23 and £4,899 / $5,008.18 / €4,749.05 respectively.

Our Ultra, in its sparkly ‘Midnight Metallic Blue’ candy paintjob, is specced with a Shimano 105 Di2 groupset.

Other than the chain, which drops down a rung to Deore (slightly heavier than the SLX chain equivalent to 105), there are no deviations to the groupset. Our large test bike features a 172.5mm crank length, 50/34-tooth chainrings and an 11-34t cassette.

Kaden Gardener / Our Media

The bike comes equipped with a Level DB56 Sport Carbon wheelset, from Ribble’s in-house component brand, Level.

As the name suggests, the wheelset has 56mm-deep carbon rims front and rear, and is built around Level hubs. Ribble claims a total weight of 1,710g for the set.

The wheels come set up with inner tubes out of the box, with Vittoria Zaffiro Pro Graphene 2.0 tyres in a 700c x 28mm width.

Kaden Gardener / Our Media

Outside of the Level finishing kit, Ribble specs a Selle Italia Model X BB FEC saddle.

All-in, the bike weighs 9.06kg without pedals.

We’re currently testing the Ribble Ultra SL on the roads around Bristol, so you can expect a full review soon.

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