It makes sence, I never have understood how the rig shape made a diferance, I just have that one experience that has made me feel that oval chainrings are better, but I have experiences that also point that round rings are better, I just had to look back at old rides and look at the starva segments .
The research is inconclusive. Interestingly one of the more consistent benefits that studies “found” is that short intense efforts see better power with non-round rings. It gets dirty when you take into consideration crank based PM’s and the way that non-round rings inflate power by something like 2-4%. For me that would be 25-50W. It’s crazy that I use a crank based PM and have seen no change suggesting round rings may be better (for me). Others say the same. I just have not come across anyone who says the opposite. That’s means nothing as my sample size is small but, just more things that make me wonder.
To anyone thinking of buying I’d research:
- Do non-round rings inflate power with crank PM’s.
- How the hip, knee and ankle joints change while pedaling with non vs round rings.
- HR and lactate production/clearing with non vs round rings.
chris froome used them, that means there must be some kind of marginal gain, maybe the gain just comes if you spend to much time looking at your stem while racing or ride at a high cadence up climbs.
I’ve absolutely no idea if I get more power when using oval rings as I’ve no power meters on any of my mountain bikes. However if I get better traction (as in less spin-outs) then I’m assuming that I’m wasting less power than with a round chainring.
Taking times off Strava is fraught with difficulties especially off-road as there’s so many other variables that unless one time is significantly faster, say 10% quicker, then as far as I’m concerned, it’s just a time that might be quicker but it might be slower.
I just wanted to add my recent experiences.
I switched both bikes (TT and road) to Absolute Black oval inner rings about 6 months ago. I really liked the feel; pedalling on an oval ring “made sense” to my legs.
As the big ring on my road bike had worn out, I went with a Q-Ring big ring (and Q-ring inner, went from 50-34 to 52-36). My road bike runs Sram Red Etap 11 speed. So I was worried the shifting would be poor. I had 30 days to return the big ring for a No-Q big ring under the Try-Q deal.
Well, the shifting is better than on my previous round big ring. I guess I hadn’t realised how worn my previous (round) ring had become (18,000+ km). So there was a very noticeable improvement in front shifting. As for use…my right patella tendon issue that was coming and going every month since I started Trainer Road about 18 months ago, has gone. I had forgotten about it until I hopped on my TT bike for TR session and then got a slight pain after. That reminded me. I wasn’t expecting oval rings to resolve my tendinitis. So I need to purchase an oval big ring for my TT bike now.
Note about my right knee
Before people say I may have a bike fit issue to be getting this injury. My right knee has had 6 surgeries, no meniscus left, hardly any bone cartilage left etc. So any symptoms with that knee is a “special case”.
Ok so I just decided to do a 20 minute power test with an Osymetric vs Round Chainring and see what the results were. Here is my video of it. I cover some installation stuff at the start.