New Syncros Capital SL carbon wheelset features one-piece rim, spoke and hub shell design

New Syncros Capital SL carbon wheelset features one-piece rim, spoke and hub shell design

Striking £4,000 wheelset underpinned by more conventional and affordable Capital 1.0s and Capital 1.0 models

Ashley Quinlan / Our Media

Published: July 17, 2023 at 2:00 pm

Scott’s in-house component brand Syncros has launched its new Capital SL and Capital SL Aero all-carbon wheelsets – and they’re quite the lookers.

The carbon rim, spoke and hub shell are all fashioned from a single mould – a monocoque – which Syncros says creates a lighter and stiffer wheelset, without sacrificing aerodynamic performance.

Syncros says it has taken a holistic approach to aerodynamic optimisations, partnering with Schwalbe to develop the new Pro One Aero tyre.

The wheelsets use DT Swiss 240 EXP hub internals inside a custom hub body specially glued into place.

The flagship wheelsets are available in two rim depths – 40mm and 60mm – and are set to be ridden by Team DSM-Firmenich riders on the Tour de France stage 16 time trial.

The Capital SL wheelset costs £3,999.80/$4,099.98/€3,999.80, while the deeper Capital SL Aero hoops cost £4,199.90/$4,199.98/€4,199.90 a set.

These top-end wheelsets are underpinned by the Capital 1.0s and Capital 1.0 models, which feature the same carbon rim profile laced to a more traditional spoke-and-hub design.

The more conventional wheelsets are priced from £1,599.80/$1,799.98/€1,599.80.

How are the Syncros Capital SL and Capital SL Aero wheelsets made?

Syncros Capital SL manufacturing
The rim, spokes and hub shell are laid up in one mould. - Ajax Salvador

The new Capital SL road bike wheels take inspiration from the brand’s Silverton SL mountain bike wheels through a one-piece rim-to-hub construction.

Syncros says each wheel is laid up and cured in a single mould, with the spokes bonded to the rim and hub shell in one piece to form a monocoque.

The brand says making a wheelset in this manner enables the rim, spoke and hub shell to be designed to work as one unit, as opposed to the traditional method of using spokes as an interface between a separate rim and hub.

Syncros Capital SL manufacturing
Once cured, the spoke and rim form one piece. - Ajax Salvador

This means there are no spoke nipples or threads to worry about, while the one-piece nature of the spokes (they also intersect physically, rather than cross over in the traditional sense) removes the need for – and possibility of – adjustment.

The hub shell interface features a slatted design, visually not unlike the splines on a Shimano HG freehub. On each end is a ‘stopper’ ridge that effectively provides a fixing ‘bookend’ for the custom-shaped DT Swiss hubs.

Syncros Capital SL manufacturing
Once out of the mould, glue is applied to the hub shell. The wheelform is then placed into a special jig and pulled apart. This allows the custom DT Swiss hub to be inserted, and for the spokes to be evenly tensioned. - Ajax Salvador

In order to insert the hubs, the wheel form is effectively pulled apart at the hub shell and set into a proprietary jig.

This serves to tension the spokes evenly, before the hub is glued into place. The jig then holds the wheel still to enable the glue to set.

Syncros Capital SL wheelsets key stats

Syncros Capital SL rear wheel
The wheelset at BikeRadar Towers is the 40mm-deep Capital SL. - Ashley Quinlan / Our Media

The 40mm-deep Syncros Capital SL wheelset we’ve got our hands on exhibits a progressive rim profile – 25mm wide internally, with a hookless design.

Meanwhile, the deeper Capital SL Aero wheelset has a 23mm front-wheel width (internal), married to a 25mm rear-rim width.

Both arc in a U-shape, with external widths tailored to the individual wheel’s role and dimensions.

Both 40mm-deep Capital SL wheels measure 31.5mm externally. The 60mm-deep Capital SL Aero front-rim profile arcs to 32mm wide, while the rear wheel is 33.6mm wide.

Throughout, a hookless design has been chosen to smooth the interface and improve air attachment between the tyre sidewall and rim (more on this below).

Syncros Capital SL hub
The wheelset uses DT Swiss 240 EXP internals, inside a custom-made body. - Ashley Quinlan / Our Media

The rim and hub in each wheel are connected by 16 spokes, with a fused one-cross arrangement on both sides.

These are staggered (i.e. not mirror images) to best balance the lateral forces each wheel will encounter. The rear wheel features a slightly broader arrangement of spoke crossovers, intended to deal better with pedalling forces.

The custom hubs feature DT Swiss 240 EXP internals. Syncros says these were chosen over the higher-spec 180 EXP innards for their claimed longer lifespan and reduced service needs – which could be handy, given the nature of the overall wheelset design.

The Capital SL wheelset is said to weigh 1,170g, while the Capital SL Aero wheelset is claimed to tip the scales at 1,290g.

Syncros Capital SL spoke and rim
The finish on the spoke-rim joint is smooth – no nipples here. - Ashley Quinlan / Our Media

The wheelset is formed using Toray T1000 M40 carbon fibre, the distribution of which was arrived at through the use of Finite Element Methods technology.

This technology enabled Syncros to simulate factors such as strength, stiffness and deflection by virtually tweaking the design through hundreds of iterations.

While this technology is employed by many brands, Syncros says initial computer modelling gave “around” a 5 per cent safety ratio (the percentage over the designed upper force limit that would cause the wheel to fail), but managed to up this to 35 per cent while cutting extraneous material.

Aero development with Schwalbe

Schwalbe Pro One Aero road bike tyre
Syncros worked with Schwalbe to optimise the wheels for the German brand's new Pro One Aero tubeless tyre. - Ashley Quinlan / Our Media

Syncros says one of the keys to the Capital SL’s overall performance prowess is in its hand-in-hand development with the new Schwalbe Pro One Aero tyre.

This 28c tyre is claimed to produce 20 per cent less aerodynamic drag at 45kph than a 25c Pro One TT, which was Schwalbe’s previous benchmark road bike tyre.

The brand measured both ‘translational’ (the impact of air directly upon the wheel) and ‘rotational’ (the impact of air interacting with the wheelset rotation) performance to arrive at its conclusions, focusing on +/- 20-degree yaw angles.

Syncros_wind_tunnel_15
Syncros says it measured airflow impacting on the wheelset, as well as the airflow interacting with it as it rotates. - Michael Riehle

According to Syncros’ data, when tested in a wind tunnel with the tyre fitted, the Capital SL wheel emerged 7 per cent more aero efficient than its nearest competitor (a Zipp 303 Firecrest).

Also tested were the Zipp 353 NSW and Campagnolo Bora Ultra WTO 45 wheels. The brand also says the shallower wheel is competitive with the deeper Zipp 404 Firecrest, 454 NSW and Campagnolo Bora Ultra WTO 60 wheelsets.

Syncros says it has tested tyres from major manufacturers, and publishes a list online of the tyres deemed compatible with the new Capital SL wheelsets.

Capital wheels for the masses?

Syncros Capital 1.0s and Capital 1.0s Aero rear wheels
The same rim profiles can be had in more traditional (and cheaper) constructions. - Syncros

There’s no getting around the fact that the Syncros Capital SL (£3,999.80/$4,099.98/€3,999.80) and Capital SL Aero (£4,199.90/$4,199.98/€4,199.90) are incredibly expensive.

However, Syncros has also launched Capital 1.0S and Capital 1.0 wheelsets, both with matching deeper ‘Aero’ siblings, at far more accessible price points.

The rims retain the same progressive internal widths and external aero profiles, and are made of the same Toray T1000 M40 carbon material.

These wheels take a more traditional approach in their design and manufacture, however, with drilled rim beds and standard spokes, nipples and hubs making up the whole wheel.

As a result, Syncros confirms that the distribution of carbon has been tweaked to fortify the wheel in key areas, such as the spoke holes, versus the Capital SL wheels.

The Capital 1.0s and Capital 1.0s Aero wheelsets use 24 DT Swiss Aerolite straight-pull spokes per wheel, attached to the rim via the DT Swiss Pro lock alloy nipples.

The wheels use standard DT Swiss 240 EXP hubs, and weigh a claimed 1,335g and 1,470g, respectively. It’s unclear whether this claim includes valves and rim tape.

The Capital 1.0 and Capital 1.0 Aero wheelsets bring the components in-house, employing Syncros-branded hubs, straight-pull spokes and alloy nipples.

In this configuration, the wheelsets weigh a claimed 1,480g and 1,630g, respectively.

Syncros Capital wheelset range prices and availability

Team DSM-Firmenich Scott Plasma time trial bike with Syncros Capital SL wheels
The new wheels will be ridden by Scott-sponsored Team DSM-Firmenich in time trials. - Luis Alcantarilla

The Syncros Capital wheelset range is available from today, with Team DSM-Firmenich riders set to use the new Capital SL Aero front wheel at the Tour de France stage 16 time trial, alongside a to-be-released disc rear wheel with a Capital SL skeleton.

The 40mm Capital SL wheelset costs £3,999.80/$4,099.98/€3,999.80; the 60mm Capital SL Aero hoops cost £4,199.90/$4,199.98/€4,199.90 a set.

The mid-range Capital 1.0s and Capital 1.0s Aero wheelsets are priced at £2,199.80/$2,399.98/€2,199.80, and £2,399.80/$2,299.98/€2,399.80.

Meanwhile, the entry-level Capital 1.0 and Capital 1.0 Aero models cost £1,599.80/$1,799.98/€1,599.80 and £1,699.80/$1,899.98/€1,699.80, respectively.

Syncros Capital SL Aero

  • Price: £4,199.80/$4,199.98/€4,199.80
  • Rim depth: 60mm
  • Rim width (internal): 23mm front; 25mm rear
  • Spokes: Carbon, one-piece
  • Hubs: DT Swiss 240 EXP, custom shell
  • Claimed weight: 1,290g

Syncros Capital SL

  • Price: £3,999.80/$4,099.98/€3,999.80
  • Rim depth: 40mm
  • Rim width (internal): 25mm front; 25mm rear
  • Spokes: Carbon, one-piece
  • Hubs: DT Swiss 240 EXP
  • Claimed weight: 1,170g

Syncros Capital 1.0s Aero

  • Price: £2,399.80/$2,399.98/€2,399.80
  • Rim depth: 60mm
  • Rim width (internal): 23mm front; 25mm rear
  • Spokes: DT Swiss Aerolite, straight-pull
  • Hubs: DT Swiss 240 EXP
  • Claimed weight: 1,470g

Syncros Capital 1.0s

  • Price: £2,199.80/$2,299.98/€2,299.80
  • Rim depth: 40mm
  • Rim width (internal): 25mm front; 25mm rear
  • Spokes: DT Swiss Aerolite, straight-pull
  • Hubs: DT Swiss 240 EXP
  • Claimed weight: 1,335g

Syncros Capital 1.0 Aero

  • Price: £1,699.80/$1,899.98/€1,699.80
  • Rim depth: 60mm
  • Rim width (internal): 23mm front; 25mm rear
  • Spokes: Syncros, straight-pull
  • Hubs: Syncros
  • Claimed weight: 1,630g

Syncros Capital 1.0

  • Price: £1,599.80/$1,799.98/€1,599.80
  • Rim depth: 40mm
  • Rim width (internal): 25mm front; 25mm rear
  • Spokes: Syncros, straight-pull
  • Hubs: Syncros
  • Claimed weight: 1,480g