Always keen to try anything that might help the body function more efficiently has led me to change one of the round chain wheels on the bike for an elliptical one. It’s a Rotor 34T Qring 110 BCD (A standard inside ring fits Shimano DuraAce but the outside ring must be a special format called OCP3 )
The ring is elliptical with the large axis lining up with the maximum push/pull phase and the short axis lining up with the dead spot where the feet pass over the top and bottom of the cycle. There are three possible settings but I used the “normal” OCP3 position choice for starters.
First time using it felt a bit uncomfortable because it felt like I had to push harder on the climbs and drop down a gear – but I was tired on the day. It was later confirmed that you do have to push harder because the extra leverage on the long axis is like a 37T chain wheel. The difference can be seen in the photo – with the round Shimano ring placed on top of the Rotor Qring.
Yesterday I went out for a second workout with much fresher legs having been sidelined for a week by a cold. The difference was amazing! The real difference is noticed when switching back to the round chain wheel – it just feels horrible – like there is this long delay as you drag everything through the dead spot. If I was unconvinced on the first outing that all changed on the second.
From the beginning I really wanted Osymmetric rings but they only go down to 38T and this represents a 42T equivalent on the long axis. That’s just way too much to push on a steep Alpine climb at the end of a hard day! Eventually I tracked down a single 50T Osymmetric ring for my outside ring. This is not quite the same pattern – it has a “dual elliptical” shape and is much more radical and apparently more effective. This might encourage me to do even more climbing with the 50T if it works so well. It should be a fairly unique set up on the bike but if the Osymetric ring is anything like a good as the Rotor ring then it should work very well. I’m not worried about “mixing” things because I found my body adapting immediately to whichever chain wheel was being used between even the elliptical and the round ones.