Beastly good wheels from the East

Rotobox carbon fibre wheels are pricey but impressive.

Rotobox carbon fibre wheels

Okay, the latest weather-based arrival from Eastern Europe is pretty crappy, unless you're a ski-ist or a suicidal pond skater. The Beast from the East Siberian Blast (© copyright all papers) is making riding of any sort pretty much impossible – so our advice is to get planning this season's upgrades for your ride (and work out how you're going to get the expenditure approved from the household budget…)

And you may as well go big from the off. Big, as in some super-trick, super-light carbon fibre wheels, from Rotobox. The crazily-named firm is based in Slovenia, like that other top-end kit maker, Akrapovic, and it's been making its carbon fibre wheels for the past decade, near the capital Ljubljana. Its wheels use a novel 'fat-spoke' design, which uses the best characteristics of carbon fibre in the ideal way. Large spokes with thin walls optimise the stiffness of the structure, while cutting weight to a minimum, which is the ultimate engineering goal on something like a wheel.

There's a 2.5mm stainless steel wire embedded in the rim for structural strength there, and the hubs are CNC machined from 7075 T6 aluminium, then bolted and bonded together with aerospace-spec kit. This design helps Rotobox make the wheels available for loads of bikes more easily – the outer rims are made to a few basic sizes and designs (including single-sided swingarm fittings), then the hubs can be machined to suit each bike's spacers/axle/brake discs. Clever stuff.

A typical pair of Rotobox RBX2 wheels for the BMW S1000RR weighs in at 6.8kg, compared with 11.7kg for the stock wheels, and 7.4 for forged magnesium competition wheels. That's almost a 50 per cent saving on weight – pretty impressive. Weight loss on rims is double-good of course, since it lightens the whole bike, but also reduces the mass that needs to be rotated as you move. Like a lightened crankshaft, it will make a bike accelerate quicker from that, as well as from lower all-up mass. In addition, lighter wheels make less work for your suspension to cope with, meaning damping can be better-optimised for performance all round.

The down side is obvious – carbon wheels are an expensive gig, due to their handmade limited run production methods. A pair of Rotobox rims will cost you around £2-2.5k, depending on application. But they are amongst the trickest things you can put on your bike – and with manufacturers adding most of the traditional bolt-ons at the factory these days (quickshifters, posh cans, Öhlins suspension, steering dampers, nice rearsets etc), one of the few really significant bolt-on upgrades on something like a Panigale or a Fireblade SP.

I've actually bought a set of Rotobox wheels myself, for a project bike, which gives you some idea of how nice they are in the flesh. They're fully road legal, and can be customised with different anodised parts, and rim finish. They fitted my ZRX1100 easily, and have given a really different, cool look to the bike…

Rotobox is at www.rotobox-wheels.com