Historic Italian manufacturer Viner’s name was saved from obscurity by online giant’s Planet X just a few short years ago, and while the brand's output may have contracted a little there is still room in the range for it to create the lightest chassis it has ever produced with the Maxima RS 4.0.
Everything is based around a race-optimized superlight 795g gram frame constructed using a proprietary blend of high mod carbon fibres for what is a clean, understated and aggressive bike.
The geometry on my XL (57cm) test bike features a steep 73.5 head angle and slacker 72.5 seat. Short chainstays and a sub-metre wheelbase combined with a 599mm stack and 399mm reach makes the ride position low, encouraging you to get into the (compact) drops of the classy Selcof bar and beat the wind as you fire yourself down the road.
The overall weight is one of the lightest on test in our Road Bike of the Year 2017 testing category (only surpassed by the lighter, smaller sized B-Twin and equaled by the super-plush Trek Domane and high-spec Canyon Ultimate) and on the climbs the 4.0 is absolutely in its element.
The superb rigidity through the chassis means little power loss as you turn the cranks, with the sportive-ready gearing making even the steepest ascents within capable reach.
The no-nonsense spec of full Ultegra, brakes and all is great to see and Ultegra remains the benchmark for slick shifts and powerful stoppers.
The Shimano RsS330 wheels are middling, however, while the hubs are up to Shimano’s usual standards; the smoothness of the hubs is testament to Shimano’s continued commitment to classic angular contact bearings over cartridge units, which has the added benefit of easier cleaning and servicing than fully sealed units.
The new 30mm deep alloy rim offers some aero gains and measures up at a couple of points shy of 21mm wide externally; internally they're on the narrower side. The all up weight of 2024g a pair is a little hefty but shows just how light the 4.0 truly is when you take these into account of the bike's overall weight.
The 330s are wrapped with 25c Hutchinson Fusion 3 tyres, which come up a little narrower, and are a little waxy until they’ve got a few long rides under their belt. Once the surface is scuffed up a little it lets loose a fairly supple feel with decent grip in all but the wettest, greasy conditions where they broke away a little sooner than top-flight treads like a GP4000 or Schwalbe One.
Ride and handling
The ride quality is decent with a solid, firm feel across rougher surfaces but great contact points in the form of the ProLogo saddle and Selcof bar wrapped in quality tape taking the sting out of any road buzz. Overall, it offers a similar feel to the firm but forgiving Giant TCR Disc for a very similar price.
The handling is quick and well suited to the RS’s overall feeling of lithe light and nimble road manners.
The sharp handling requires your attention when sweeping down descents as it requires far less input from you to make big direction changes. We love the way it reacts but some of our test riders did feel the 4.0 erred towards feeling a bit ‘nervous’.
In all the 4.0 RS is an unashamed traditional racer's machine. It's light (and has the potential to be built into a serious weight weenies dream machine), it's rapid, and it's sharp handling.
At the money it’s a great buy, and if you’re the sort of rider that likes their bikes this way, and aren’t yet sold on the disc revolution then the Maxima is a truly discerning choice.