Mavic's new 40mm and 25mm deep carbon clinchers have wider aero profiles and wet weather braking performance almost equal to that in the dry

Mavic has launched a new generation of its carbon clincher wheels, comprised of the 40mm deep Cosmic Pro Carbon SL C with a claimed weight of 1450 grams and the 25mm Ksyrium Pro Carbon SL C weighing 1390 grams.

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Mavic claims new standards of braking consistency in wet and dry conditions and of precision of the rim’s profile. Its new rims are also wider at 17mm internal, 26mm external for the Cosmics and 17mm internal, 25mm external for the Ksyriums. And they use a U-shaped NACA profile for aero efficiency.

New production methods

Mavic has invested a lot of time and resource into its new rims, which have a claimed weight of 450g for the 40mm deep Cosmic and 400g for the 25mm Ksyrium. Creating a carbon clincher rim profile and its braking surfaces requires moulding to very close tolerances and Mavic has developed its own proprietary processes to achieve this without subsequent machining of the rim, as this can lead to cut carbon fibres and damage to the rim’s integrity.

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The company has a patented process which uses a laser to prepare the braking surface. This burns away the surface resin leaving the carbon fibres intact and exposed. It has also developed a heat curing process to ensure that its rims can tolerate braking temperatures of up to 200C, which is at the extreme of potential real world conditions.

Ksyrium Pro Carbon SL C wheelset has a claimed weight of 1390 grams

Ksyrium Pro Carbon SL C wheelset has a claimed weight of 1390 grams

Better stopping, more aero

Many carbon rims have two or three times the stopping distance in the wet as in the dry, but Mavic claims that its new rims stop almost as well when wet with the supplied yellow Swiss Stop pads.

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Mavic has also tested the aero benefits of its new rims. It started by gathering data on the real world wind yaw angles experienced when riding, which are rarely much above 5 or 10 degrees. Wind tunnel testing showed best in class results for its 40mm rim at these lower angles.

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The Cosmic Pro Carbon SL C also uses new elliptical steel spokes to help reduce air resistance. And both Mavic’s new wheels run on the company’s recently introduced Instant Drive 360 aluminium hubs with 9 degree engagement and compatibility with a wide range of axle standards. They’re available both as rim and disc braked versions.

Brake track is finished using lasers to prevent damage to the carbon lay-up

Brake track is finished using lasers to prevent damage to the carbon lay-up

Availability, prices and warranty

UK launch date for the Cosmic Pro Carbon SL C is 15 March with a price of £1450, with the disc braked version available from 15 April at £1500, while the Ksyrium Pro Carbon SL C will be available from 1st June also priced at £1450 for the rim braked and £1500 for the disc braked version. All come supplied with Mavic’s own 25mm tyres. There are also tubular versions of the wheels available.

Mavic is putting its resources behind the new wheels, offering a pre-purchase test programme called Riding is Believing through selected dealers. It is also offering a new warranty called Mavic Care Plus which offers a free third year and discounted crash replacement.