On-the-road performance benefits of non-round rings are hard to quantify, but they feel smooth and certainly don’t do any harm – apart from in the wallet department.
A set of Osymmetric rings – as used by Chris Froome – will cost around £240 while David Millar’s favourite Rotor Q-rings are £175 per pair. A set of Doval rings? Just £79.99.
Made in South Korea and brought into the UK by Fraser MacDonald, the rings are machined from 6061 series aluminium. The rings look like a hybrid of Rotor and Osymmetric’s designs, in that they're not quite oval, but also not as sharply angled as the latter.
Setup options are 52/36T and 50/35T for 110BCD compact setups and 53/40T and 52/39T for traditional 130BCD. The Doval rings are compatible with both five-bolt Shimano or SRAM and Campagnolo (compact sizes only), thanks to a clever oval bolt hole that accounts for the single odd bolt placement on Campag cranks.
There’s a gold anodised piece that screws onto the big ring to allow a tailored set-up much like Rotor’s five-point adjustment system. It’s simple to get to grips with – just screw the piece into one of five holes that each offer a +/- 1.2 degree change in rotation. Position one (furthest to the right) produces the lowest inertia for the shortest power output angle. Position five (far left) produces the highest inertia for the longest output angle.
This anodised piece can be mounted in one of five configurations that changes the angle of the rings in relation to the crank arm
The further forward you go in relation to the bottom bracket, when time trialling for example, the later you’ll want the powerful downstroke to come in the pedal cycle, so the higher the choice of setting. As with Q-rings, the recommended starting point is the central position three configuration.
The rings pictured here are the 53/40T pairing from Doval’s Light range, which may account for their slightly flexy nature – this could stiffen up once installed though. The machining is also a little rough in places, but nothing that a little at-home honing won’t sort – and considering the price this shouldn’t put you off from the outset.
If you want to get hold of a pair, you can buy them through Amazon in the UK.