[Closed] Oval chainrings. Worth the hype?

I have one fitted on the Bronson, only reason really is that it seems to smooth out the power on climbs, and as I like using a SS on the rear, this helps maintain traction on greasy stuff.

I had then on my road bike, I thought they were fine, felt they made little or no difference to me or my pedalling.

My eldest noticed when he replaced his bike and the new one came with a round one. He now has one back on the new bike.
My youngest didn't notice his new bike had an oval, but immediately started setting Strava PB's up and down, particularly on steeper climb stuff in granny ring he seems to benefit.

I'm going to try one on mine when my ring wears out.

I bought one just because it was the cheapest chainring at the time, didn't really make much difference that I could tell. Just felt a big pogo'y when i first got on because my other bikes dont have it but soon adjusted.

Depends on your pedalling style. I find it helps with low cadence climbing, but it's not a massive difference.

Similar to nobeer I found that an oval ring helped smooth out power delivery on my Soul when it was running 1x9 with an 11:32 cassette. IME it does help maintain traction when you're out the saddle muscling/struggling your way up a climb.

Don't really notice it for along/down.

I like them but don't pretend they make a huge difference to my riding, the bike I do most miles on has a standard 50t big ring and oval 34t granny ring.

Climbing/spinning does feel smoother in the granny ring, but that might just be because I'm not as crossed up as I would be in an equivalent ratio in the big ring.

I've had professional coaches agree that spinning higher cadences can help the legs recover from high intensity efforts quicker, and that oval rings can help smooth out high cadence spinning, ergo oval rings might sort of contribute to better recovery or less fatigue.

I also sort of buy into the engineering behind how they smooth out power delivery, so will always run one on my CX bike, I'll take any help I can get on muddy courses!

BUT, big BUT, I sort of regret putting them on my road bikes as now I feel sort of committed, I have a morbid fear of knee injuries and over-use injuries, so feel I should keep my setups consistent across my gravel bike, winter road bike and summer road bike. That's three sets of oval rings, spendy!

if it's just one £35 ring on a 1x MTB I'd give it a shot, satisfy your curiosity at least.

Got into them when my hip issues (and as a consequence knee issues) were acute. Work for me.

Some like 'em, some don't. Some see/feel a difference, some don't.

Probably fair to say, the jury's out.

For me I find they help smooth out my choppy pedalling style but the bad habits resurface at high cadences, for me that's somewhere around 110-120rpm.

They feel smoother to my mind.

Ie. On my road bike I don’t have them, I do on my MTB. I can tell the difference.

I had one a few years ago, felt it made a difference on climbs, but I quickly got used to it, that said I’d have another one!

Unpopular opinion: I reckon they're more use with flats than with SPDs. I find (as a basically lifelong SPD user) that when I'm on flats, my feet can come off forwards on steep climbs. This happens less with the oval ring, which is good.

Honestly I'm not sure they make much difference outside of that but YMMV.

Have a cheap Superstar oval 1x ring on one bike, like nobeer and others have said, just seems to smooth out power delivery, especially on long steady climbs. I like mine.

Looks like the majority seem to like them.
It's for my MTB and I use flats. Do a lot of hill climbing and do struggle to keep up in the group I'm in sometimes so might try one out.

Where's the best (cheapest) to get them from? It will replace a 34t chainring on a Shimano slx 11 speed setup.

I'm trying one on my Soul at the moment (got it from Amazon where they can be had pretty cheaply) - can't say I've noticed a benefit or not yet, but haven't noticed any downsides either.

Superstar, probably.

https://www.superstarcomponents.com/en/raptor-oval-chainring-96bcd-asymetric-narrow-wide.htm

These are the ones I'm using, although they're 104 BCD:

https://www.amazon.co.uk/gp/product/B071JX8P39/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

On my Jekyll FS the oval ring seemed to reduce pedal bob and it did the same on my Fatty.
On the SS it just seems to feel better when I'm out of the saddle on a long climb.
I'd have one on the BMC if they made a belt drive oval.

Ordered from the superstar link that martinhutch posted.

I'm hoping it will help with the climbing and reduce strain on my knees as they were struggling last night riding up winter hill at rivington.

All a great help and sorted within an hour of my first post.
Quicker than bloody Amazon 😎

I’m hoping it will help with the climbing and reduce strain on my knees as they were struggling last night riding up winter hill at rivington.

Too late, I know, but wouldn't a 32 oval be better if you're suffering that much? An oval will make it marginally easier, but only by 'half a gear' or so.

I bought one by mistake but decided to give it a try.

32T oval on a full sus 29er. I does seem to smooth out the pedal stroke and encourage me to spin my legs a bit quicker, which i always struggled with off-road as I used to always mash too big a gear.

Worth a try I'd say

Out of the saddle climbing is where I notice it. With round rings I always found there was a slight ramp up of effort as you get over the top of the pedal stroke and this could often make maintaining traction difficult if the surface is loose or slippery. I have not found a downside to them and price is similar to round ones.

It’s for my MTB and I use flats. Do a lot of hill climbing and do struggle to keep up in the group I’m in sometimes so might try one out.

I'm not sure a chainring is the answer to this, unfortunately. Good luck though.

Do a lot of hill climbing and do struggle to keep up in the group I’m in sometimes so might try one out.

Yeah, I'd be dubious about any claims of extra power etc. Possibly extra traction, possibly feels smoother, possibly less strain on knees, but wouldn't say extra power.

I also don't think you need to change ratios as the oval effectively does this for you anyway, a 32 oval is 30* at the low points (where you knees are weakest, hence less strain, smoother stroke as your leg doesn't slow down over the top) and 34 at the high points where you have most leverage. Changing ratio at the same time as going oval will just confuse the hell out of your legs, you'll just end up in the same gear at the easy bits and a 4 tooth bigger gear at the hard bits!

*I've used a 2 tooth difference for simplicity, think absolute black use some weird percentage ovality which probably equates to 1.76 teeth or something...

only reason really is that it seems to smooth out the power on climbs

This and he fact that less lumpy power delivery returns better traction on loose climbs

Yes
But they aren’t all the same. AbsoluteBlack direct mount ones work really well for me and last ages

Find me a world champion or world cup xc rider exclusively running oval rings.

All of the roadies gave them up years ago.

All of the roadies gave them up years ago.

You mean roadies like Chris Froome and Bradley Wiggins, both of whom won TdFs and Giros d'Italia on oval, as recently as 2019?

the fact that less lumpy power delivery returns better traction on loose climbs

Absolute Black's mantra is "Traction, traction, traction"

@flyingpotatoes - a 32T oval gives you exactly the same overall ratios as a 32T round, it's just that the torque varies throughout the pedal stroke. If you are struggling with a 34T chainring then drop to a 32T or even 30T, doesn't matter if it's round or oval.

Using an oval for a few months and then getting on a round is really noticable but only for a mile or two then it normalises. The theory is sound, in practice you can feel it so I'd say every little helps?

Liked them on the MTB with a 1x but not so much on the road with a 2x. Might just be me setting it up but going back to round sorted out my shifting issues.

Quick update.
Went out this morning at rivington for a first ride with the oval ring.

It definitely seems to smooth the pedal stroke out. Very subtle but I think I might like it.

Will see how I get on when I go out with the big boys tomorrow night.

Also the knee pain I've been getting is due to working from home and sitting on a dining room chair. Went into the office to get my office chair and that seems to have helped with the knee issue.

Without reading the other comments I would say no they're not worth the hype. I have an oval ring on one bike and a round one on the other, I don't really notice when I swap between the two. If you need a new chainring then try oval but not worth ditching a perfectly good round one to do it.

I quite liked the one I had on my Orange. I ride flat pedals and don't have mega-range 12sp so that slightly easier feeling at the lower end suits me nicely.

Waiting for Superstar's next sale to pick a few more up cheap.

Tried Rotor back in 3X days, and absolute black on 1X.
Went back to round on both occasions, I did not get on with them, especially on steep climbs and lumpy, loose climbs.

In any tests, the only power benefit was in very oval rings, so the crazy shaped Osymetric's are the closest you get that are approaching a measurable difference.

My Soul seems great with the oval ring on, however I changed loads of stuff at the same time (moved to 1x11, lighter fork, lighter wheels) so suspect most of that will be down to the 5lb weight reduction compared to it's previous build.

Haven't detected any downsides though (and it does seem to pedal very smoothly) so can't see any reason to change back.

I've yet to see any tests showing they increase power, so it looks psychological only to me.

Lol @ 13thfloor, epic fail Continuity!

Tbh what the pros do is rarely relevant to what us lot do.

If you are interested in a summary of the science available.
Summary - no benefit to power in the real world, but if you feel they work then carry on.

I thought they were more to make climbing a bit easier?

I've found that the oval does makes the pedal stroke smoother especially wearing flats when climbing.
I haven't found it gives more power. Only an ebike will give me more power

too much of a gamble as there would be no cancellation or insurance cover due to C19

I think they do to an extent, on climbs where spinning out and losing traction could be an issue. Seems to even out the power, and so don't need to focus so much on maintaining a smooth cadence.

Or mibbe it's placebo, but it works for me.

It probably depends on what you are riding at the time. I have a Superstar Oval on my rigid bike in 32T. It felt weird whilst JRA at first, but now just feels normal. The only time I notice it is on a steeper climb where there is a little bit of extra momentum at the end of the stroke. A bit like riding with bigger or heavier wheels. This helps on tech stuff, so whilst if you are power metered up on a smooth test rig it might not show up, I think the extra ease of pedalling on rough stuff makes life easier on your legs, probably reduces fatigue and probably helps you get more power down. Slightly.

But since they are the same price, and they are slightly better, it's a no brainer for me. Only issue is that they are bigger so you need more clearance. I'd go 34T on my bike but I don't think it'd fit.

When the XT 3x10 finally died on my XC bike I switched to 1x11 with an oval chainring. I honestly can't say that I notice a difference in how I pedal but it does seem to have reduced the pain I get in my knees and for that alone is worth it.

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://singletrackmag.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?

https://crosscountrycycle.wordpress.com/2014/10/08/out-of-round/

https://books.google.co.uk/books?id=wMgEBAAAQBAJ&pg=PA178&lpg=PA178&dq=phil+burt+oval+chainrings&source=bl&ots=fFYCFz_um5&sig=6yYUUjvf5mtD2kkmNNtcB_c4Iks&hl=en&sa=X&ved=0ahUKEwjr6t2MkOfRAhXpAMAKHe2qDLkQ6AEIIjAB#v=onepage&q=phil%20burt%20oval%20chainrings&f=false

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.