Bad knees, a dream to become a better climber, or simply to get a smoother cadence on the flat? Ovalised chainrings have been available for a long time now, in different shapes. Theory is simple. The anatomy of a cyclist result in two dead spots throughout the circular motion. When the pedal is on the top and at the bottom. The cyclist is simply not able to generate the same watt as when pedals are horizontal. Round chainrings do not consider this issue. Instead it is the cyclist issue to cope with and improve his cadence technique. Especially cruel hills stress any effort to maintain an even cadence working through the dead spots.
If theory is simple, why then do not major brands offer ovalised chainrings? That would be violating the principle of standardisation. Simply too complex to offer to many alternatives. The analogy here would be crank arm length theory…Shimano had a go in the 90’s with Biopace. Offering a high grade of ovalisation and not entirely well thought over. Ovalisation can be a very personal choice, where Bradley Wiggins TT chainrings are proof of this. Lately there have been a kind of revival as for ovalised chainrings, where Rotor is one of the bigger brands with Thor Hushold as the front man.
Ridea offer three different levels of ovalisation. We do offer the least ovalised alternative (13 grades). These chainrings are easily mounted to your regular 5-bolt crank arms. There is no issue as for the front mech functionality. A standard Shimano set of 53-39 (130bcd) is a mere 124 gm. The chainrings are CNC machined out of 7075 – T6 Alloy and have a Keronite coating, which we have found durable in direct comparison with high quality Stronglight Ct2 chainrings. This level of ovalisation is simply a good starting point. Basically no big deal. You will notice less stress for your knees (Especially on the turbo trainer), a better rhythm as for your efforts to conquer your favourite climbs, and a smoother cadence on the flat. More info is found at: http://www.ridea-international.com/en/pro_02.asp?seq=32