Non-circular chain rings have been designed with the purpose of increasing the moment-arm of the chain in relation to the bottom bracket when the pedal is at the power phase of the stroke. Numerous shapes of eccentric/non-circular chainring have been devised with controversial results reported in terms of performance. A study looking at BMX cycling observed that no benefits in performance of elite or junior cyclists could be gained using a Q-ring non-circular chain-ring. This is in line with a number of studies showing that it is unlikely that these implements have the potential to influence cycling performance. However, further studies looking at the position of the largest leaver of the chain-ring could be explored in order to determine if this configuration can be optimised based on individual's pedalling technique.