Wilier’s new Granturismo SLR endurance bike boasts a clever flexion device

Wilier has launched its new Granturismo SLR endurance road bike, with the express aim of targeting riders who want a top-level road bike without the downside of an overly aggressive riding position.

The endurance bike concept is nothing new, but has arguably been transformed in recent times by crossover with the world of gravel bikes. However, Wilier claims the new Granturismo SLR offers race-bred performance and technology, designed for use on the road, and will work out faster for the average rider than its Filante SLR race bike.

The Granturismo SLR features an Actiflex 2.0 device – a kind of suspension system that pivots on a bearing – with learnings taken from the brand’s Cento10NDR bike, which featured first-generation Actiflex to add compliance.

The new bike features the same high-modulus carbon fibre as the Filante SLR, as ridden by WorldTour team Astana-Qazaqstan, but with a tweaked layup to support Actiflex 2.0’s properties.

It’s available now, with prices starting at £7,660 / €7,400 for the cheapest SRAM Force eTap AXS and Shimano Ultegra R8170 Di2-equipped models, rising to £12,070 / €11,700 for a Campagnolo Super Record EPS build.

Actiflex is back

Actiflex 2.0 evolves the original Actiflex concept seen on the Cento10NDR road bike. - Wilier

It’s been over a year since the Actiflex-equipped Cento10NDR was discontinued, but with the Granturismo SLR, the comfort-enhancing technology has made its return.

This time, it’s said to be improved, with the Actiflex unit housed around the top tube-seatstay junction.

“Around” is the key word here, because the seat tube is not attached to the seatstays. Instead, it proceeds directly downwards to the bottom bracket in a design reminiscent of Lapierre’s Xelius, Pulsium and Aircode bikes.

Wilier says the remodelled Actiflex tech enables the rear triangle to flex substantially more than it would otherwise, with the Actiflex unit physically compressing and pivoting around a bearing when riding over rough tarmac.

The result? Greater claimed vertical compliance with what Wilier calls “MTB-like” suspension, but with a relative saddle-bottom bracket position that remains unchanged.

The design sees the seatstays join to the top tube via a pivoting bearing. - Ashley Quinlan / Our Media

The reasoning for the design rests on guaranteeing the rider their optimal riding position at all times – a position often arrived at through great bike-fitting expense, says Wilier – which should translate into a more comfortable, efficient ride over longer distances.

The Actiflex device comes in two versions; a softer unit is recommended and supplied as standard with the XS, S and M-sized frames, and a stiffer version reserved for the L, XL and XXL models.

Wilier says you can switch out the device at point of purchase if you really want a more compliant or rigid experience, but that the default supplied units should suit the vast majority of riders who buy the relevant-size bikes.

It’s also possible to replace the Actiflex unit post-purchase, so in theory you could have both units and switch them out to suit a given ride.

The Italian brand is also experimenting with 3D-printing technology for future iterations of Actiflex. Theoretically, this could enable custom units to be made, which are tuned more accurately to rider weight and desired compliance levels.

Rigid Filante SLR-grade carbon and a more friendly geometry

It might be an endurance bike, but the Granturismo SLR is designed to be ridden like a race bike. - Wilier

Despite being an endurance bike, Wilier is at pains to point out that the Granturismo SLR shouldn’t be seen as a second-tier bike. In fact, the Italian brand says it will be the optimal bike for most riders, with the Filante SLR better suited to racers with greater flexibility.

With that in mind, the Granturismo SLR features the same carbon fibre with liquid crystal polymer mix as the Filante SLR race bike, just with a modified layup to enable more vertical flex in the rear triangle.

Wilier says it needed to add some extra carbon fibre in specific areas to provide the strength necessary to cater for the compliance Actiflex 2.0 brings, but that the modifications should only serve to improve the ride over longer distances, rather than slow the bike down.

The seatstays are also connected by a torsional support bridge. For previous-generation bikes, Wilier offered the bridge as a mounting point for rim brake calipers, but it has stuck with it here purely for its bracing properties.

The geometry is taller and slacker at the front end compared to a traditional race bike such as the Filante SLR, with the long head tube particularly noticeable.

	XS	S	M	L	XL	2XL
Seat tube length (mm)	450	480	500	520	540	560
Top tube length (mm)	517	532	547	558	574	592
Head tube length (mm)	117	136	157	177	196	217
Head tube angle (degrees)	71	71.5	72	72.5	72.5	72.5
Seat tube angle (degrees)	74.5	74	73.5	73.5	73	72.5
Chainstay length (mm)	409	409	412	412	412	414
Wheelbase (mm)	977	985	995	1002	1013	1027
Stack (mm)	527	546	566	586	604	625
Reach (mm)	369	374	379	384	389	395

A tall head tube dominates the front of the bike. - Wilier

Wilier points out this should enable more riders to find their perfect riding position without resorting to fitting excess spacers (Wilier supplies 30mm of spacers to help riders optimise the height of the front contact points) on a bike that features a more aggressive geometry.

It claims this carries aesthetic benefits, plus better preserves the Granturismo SLR’s handling characteristics.

The chainstays remain compact to retain sharp acceleration, joining to a chunky bottom bracket area. Wilier has thickened the brakeside chainstay and fork leg, it claims, to balance the unique forces associated with disc brakes.

Cursory attention has also been paid to aerodynamics, with the wide Filante SLR-esque fork, integrated Zero bar-stem setup and D-shaped aero seatpost said to cut a cleaner line through the air.

That said, the overall tube profiles suggest a bike optimised for aero stability rather than out-and-out speed.

The wide fork crown and fresh air space around the rear wheel offer clearance for tyres up to 32mm wide.

Wilier Granturismo SLR availability and prices

The Granturismo SLR is available now in six frame sizes. Reflecting Wilier’s positioning of the bike as on a par with the Filante SLR, it can be bought with an array of top-tier groupsets.

Prices start from £7,660 / €7,400, and rise to £12,070 / €11,700.