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I test rode a bike this week with a round ring and it's hard work in comparison
Curse this thread!
I'd talked myself out of buying any more oval rings, decided I'd rather save the money and just get used to round rings again, but as my knee gently twinges at me from under the desk and I put the finishing touches to a 300km mega-climby Cairngorms gravel loop, I'm thinking I probably need all the help I can get.
Just wish Absolute Black would hurry up and make some rings compatible with 2x GRX...
https://singletrackworld.com/forum/topic/i-think-oval-chainrings-give-me-knee-pain/
There was a thread on here (and talked about elsewhere) last year suggesting oval rings actually cause knee problems. I had big problems with my knees a few years ago and going back to round chainrings noticeably improved the situation. I think it's something to do with rhythmic changes in resistance and cadence from the oval ring causing a kind of successive impact or strain on the knees when pedalling.
I also found that after several years and many thousands of miles on ovals (yes I was one of the early fanboys) the benefit was lost because my muscles had gotten used to the way they pedal. So much so I had actually gotten weaker and it was starting to feel like the oval was making it harder, not easier. Really noticed this most when I went back to round. Took months to get my leg strength back feeling normal again.
Your results may vary...
I have run both and they are the Emperors New Clothes in my personal experience.
I notice absolutely no benefit. In fact at very high speeds and cadence there is a specific place in the rotation where there isn't enough to 'push against'.
What is meant to add something at low cadence/high torque actuals detracts at high cadence/low torque when spinning fast over relatively flat ground or on road connections.
I wouldn't be in a rush to change back to a round ring, but when the oval is worn out I will fit a round ring.
Personally I found climbing with a 32 oval easier than a 32 round. Heard they can wear clutch mechs out quicker which makes sense as my clutch was shot on the old mech (probs coincidence I know) Back to round on both the bikes now though
I reckon the Absolute Black ones really do smooth the power a fair bit.
Apparently there's a big difference in clocking and ovality between brands.
These just work for me. I stand to pedal A LOT and the effect is the same with flats or clips.
Ever seen that Fabien Barel climbing video https://www.pinkbike.com/video/254149/ and wonder how he is so smooth at low cadence on such steep ground. Well that AB chainring has a bit of that feel to it. Not saying Barel uses oval he's just a riding god.
Love em, round feels strange now, lumpy.
After having praised oval earlier I am now thinking of ditching the oval on my rigid bike.
I went on a long ride on Sunday which included a lot of cyclepath that had been railway, so it was quite flat. I found that if I span at 90rpm as I wanted to, each pedal circle the wheel would overtake the pedals and the chain went slack, then when the wheel caught up it clonked on the ratchet. Like pedalling with a really wild pedal stroke, except that it was only 90rpm and I am usually pretty smooth at that cadence. It was clearly caused by the change in ratio through the stroke.
There was another trail that was not steep but somewhat rocky, and I tried to spin up it. I found it surprisingly difficult to get a rythmn going. I think that the feedback from hitting the stones was variable - like if it hit at different points on the chainring I got a different feeling which was really annoying and wearing after a while - like riding a really bad FS frame.
So I think I will get myself a 34T round (which is the size I really want anyway on the Salsa but 34 oval didn't fit) and put the 32T oval on the Trek which is FS and mostly used for more technical trails. I still think oval is great for technical trails i.e. grinding up steep stuff, so I don't think I'll go back to round on everything.
Having read this thread I thought I'd try them on my road bike again. Decided to just fit the inner ring and leave the outer as round.
I'm actually liking this setup more than I thought I would.
It takes about 3 pedal revolutions at the start of the ride to workout why the inner ring feels a bit strange and then, I think, it feels generally pretty good.
No idea if it's making any tangible difference but I think I'll persist with it for the moment.
That's how my winter bike is set up, I was too cheap to go oval on the big ring as I never plan to spend much time in big ring during spinny winter base miles rides. I'd swear using the inner ring feels smoother to spin away in but there could be other factors e.g. better chainline.
I'm trying to figure out now if slightly achier knees is due to more miles on gravel bike with round rings and then jumping back on road bikes with Ovals. Wish someone would hurry up and develop some 2x oval rings for GRX!
I found that if I span at 90rpm as I wanted to, each pedal circle the wheel would overtake the pedals and the chain went slack, then when the wheel caught up it clonked on the ratchet. Like pedalling with a really wild pedal stroke, except that it was only 90rpm and I am usually pretty smooth at that cadence. It was clearly caused by the change in ratio through the stroke.
That sounds weird! Is your pedal stroke basically SO good that your leg is now accelerating through the low point of the oval, speeding the wheel up so it then catches up with you when your leg slows down at the high point of the oval?
I think others have mentioned issues which sound like they had basically trained themselves to spin round rings so smoothly that their legs over-compensate if they switched to oval.
The reason you are getting such varied opinions was addressed in one of the first replies. It really does depend on your peddling style. I have one on one bike and a round one on the other, but i cant really tell the difference. I cycle on the road a bit so thats given me a more "circular" peddling style. My mate on the other hand has a very left - right - left peddling style and for him they are revolutionary (ahem) and he feels big gains using them.
Sorry about that shocking pun BTW.
Another aspect that doesn't get mentioned very often is on a suspension bike the oval ring is continually changing the anti-squat number. Also where the rider puts the most power in is actually the softest point in this which is not ideal. I'm not sure how noticeable this is, maybe it depends on the bike, but some people say it causes bob.
Is your pedal stroke basically SO good that your leg is now accelerating through the low point of the oval, speeding the wheel up so it then catches up with you when your leg slows down at the high point of the oval?
I dunno about it being amazing but I have focused on pedalling style a lot on road (you have to do something to alleviate the boredom..) and this might be part of it. Switching to a higher gear was fine I suppose because I was mashing more - likewise grinding up hills. Until Sunday most of the riding on that bike had been hilly roads or steep trails which I suppose is why I posted a positive report up there ^^. And it was an extreme case - 18 miles of almost completely flat or slight gradient trails is unusual here.
I also use SPDs off-road mostly, perhaps because I'm accustomed to that style of pedalling which might also be why I dislike pedalling on flats.
I wonder if an oval inner and a round outer would be the ideal setup on road, given you use the inner for climbing more?
I took the 32t oval off my rigid bike and put a 34t round on. It's better for spinning, but on steeper low cadence stuff it lacks a bit of 'bite' and I feel the lack of momentum. Having said that, I found some new trails that were pretty steep and I cleaned it all with aplomb despite not having done much riding in the last few weeks, so I didn't seem particularly hampered by this. Then again they were new trails so not exactly scientific.
I have put the 32t oval on my XC FS bike, where it may be better suited since it does a lot more steep grinding.
I wonder if on a road or gravel bike it would be good to have an oval inner and a round outer? EDIT this seems to be a thing.
I'd need 110mm BCD four bolt asymmetric pattern for my FSA cranks, looks like only Absolute black do them, not exactly cheap.
I've got a Superstar 34T oval on my MTB and an AB oval inner / round outer on my road bike.
I wonder how much they differ in ovality now you mention it. I notice the difference slightly when swapping between chainrings on the road (for about 10 seconds)
Seems that some are more oval than others.
I have Absolute Black oval rings on my road bike and on my trail bike. They work well for me and I can definitely sense an improvement on the climbs. I don't spin at a super high cadence, instead preferring to destroy my knees pushing big gears. I guess this is why I don't suffer the issues found by those who spin more.
OvalTech was a thing in the late 80's I think 'cos my Raleigh Mirage had them.
IIRC their supposed benefits were debunked and I'm surprised to see them back.
I love mine (Absolute Black) on techie climbs - it just helps a little on those bits where it's a struggle to get the cranks over.
I use a 30t on Eagle and like the 30x42 and 30x36 for those type of bits. The 30x50 is too low to make any progress - better on long drags when tired.
OvalTech was a thing in the late 80’s I think ‘cos my Raleigh Mirage had them.
IIRC their supposed benefits were debunked and I’m surprised to see them back.
This has been done to death, earlier incarnations of oval tech had the ovals at 90 degrees to current designs, e.g. the 'high' spot was located exactly where the knee was weakest.
I'll concede though that the benefits of the newer designs seem difficult to pin down or measure, most of us appear to like them because the 'feel' nicer. It's pretty telling though that team 'marginal gains' Sky, and Froome in particular, still run them.
I'm still torn, will probably get some AB for my gravel bike as I would like to lower gearing anyway and AB rings aren't much more expensive than Shimano equivalent. They also have a useful 2.5mm offset which would improve the chainline of my GRX drivetrain, although probably at the expensive of having to replace my GRX front derailleur with a 105.