change your channel name to "Bike Fit Speculator". This is pretty unscientific babble and helps no one. At least buy ring, try it out and tell us your opinion. Do you even ride?

Two weeks ago I changed my compact Ultegra rings to Absolute Black chain rings. I have set a rash of PR's on Strava. I recover much quicker between intervals. Climbing hills in the big ring that I couldn't before. Both clubs I ride with have noticed a dramatic difference. All I can say is they certainly work for me. I will never go back to round rings again.

A welcome discussion of the topic. A few points to make at random. I've used homemade chainrings for over 30 years. A few seconds into the first test ride, I realized that my new oval sprocket made the finessing of the crank, which I had struggled to achieve with a round sprocket, much easier. i should say that I was, and am, a technique junkie and a tactile pleasure addict. Both traits are I believe helpful to discover the benefits of non-circularity. I have let a few people try the sprockets over the years, at least one of whom could detect no difference in feel from round to oval(!) In tests, the subjects are unlikely to be experienced with non-round sprockets, reducing, in some cases, their benefits. It is uncertain that such benefits could be realized in a few months, since it takes years to master the turning of a crank attached to a sprocket of any shape. In the 1950's, Japanese experimenters found the most efficient speed of a human-turned crank to be around 55 rpm. Such a speed is too slow to develop power on a bicycle, for the same reason that it is difficult to develop power in a car engine at low rpm. Which brings us to one of the shining benefits of oval sprockets: because the duration of the dead centre zones is shortened, the rpm of the crank can be dropped from the typical 90 to, for me, probably around 70. For anyone like myself, with long, heavy-seeming but not terribly well-muscled legs, this is a welcome reduction, given that, as in running, consider energy is wasted in simply moving the legs. Ah, the terrible Bio-Pace. When these abominations appeared decades ago, I noticed that they turned the classical oval sprocket idea on its head by coordinating the dead centres with the large diameter of the sprocket. A friend of mine had installed them on his bike, and all I could do was suggest that he try a little experimental radial displacement (there being, after all, five positions to choose from) to see if they could be brought a little more in line with a correct orientation. I would say, learn the mechanics behind the idea of non-circularity, get yourself an oval sprocket- one designed by someone who understands the mechanics- and give yourself time to learn how to use it. At very least, you'll feel new comfort, and very likely develop greater efficiency in moving your bike. Frankly, my own long experience raises the question of how anyone could fail to realize these benefits.

People keep getting it wrong about the old Biopace chain rings. The whole purpose of Biopace was to even out the peddle stroke through the dead spot so they were the exact opposite of the current batch of oval chain rings. Specifically the most leverage was through the dead spot and the least leverage through the area of highest power. The idea was to maintain that constant power through the stroke. I think I still have an old Biopace ring in may Garage...

My uncle did a biometric study and power analysis on this many years ago (recreational rider, exceptional engineer) and did find some benefits - enough that he had them on his bikes, though he built his own chainrings - and bikes.

You missed probably second, the most important thing: pedals- clips vs flats and how power is transferred. Ovals might be a game changer for flats.

I have ovals on both my MTB and road bike. The most obvious benefit is on MTB for long technical climbs, low cadence, at the point when you are about to give up. To overcome the dead spot, at least with a 1x setup, with less effort enables you to stay on the pedals further up the climb. Whether I saved energy, or just was enabled to use more I dont know, but the sensation of being able to push further is great, and I belive the oval enhances traction. As for the road bike, I belive the rings needs to be less oval than for MTB. When going with higher cadence and less force, the smother feel of a almost round ring feels right, but as on the MTB, on climbs and string head wind, when the pedal force increase, the benefits seems more noticeable. My Strava times improved for my commute width the ovals on the road bike, and I belive they had something to with it.

I've converted all of my bikes to dual cam rings (DOVAL). I love them and went back to regular round rings whilst waiting for the last set to be delivered. I felt slower and overall course was slower 2 mins over 42 miles climbing 2300ft. I'm no athlete, just a regular overweight guy who loves cycling. But frankly it wasn't the speed it was how I felt at the end of the ride. I was aching more than when I ride centuries. I've been using non-round rings for 2 years now cycled 150 miles per day climbing 5000ft per day, I don't think I have now adjusted to them I could go back without an unpleasant adjustment period. It's not the mathematical mechanics of the ring, it how quickly you pass through TDC and BDC and the resistance you feel doing it. You are back on the power quicker with what feels like less effort. I'm using 50/39 rings.

About a year ago I went to an Absolute Black oval ring on my 1x11 MTB that I use for marathons (Cannondale Scalpel). I went with the same number of teeth as my previous ring (30T) -- the cassette is 10-42. I found the oval to climb better than the round, especially in the most technical spots where cadence can dip really low. As well, on steep climbs up loose gravel, I find myself over-torquing a lot less. YMMV, but it's definitely been a good upgrade for my riding style.

Love your videos. So nice to see and hear calm and reasonabe approach to tricky questions.

one big point to look out for is that a lot of power meters aren't compatible with non-round chainrings and a lot of research is actually invalid because they don't account for this

I run ovals on both road and MTB bikes, I find the biggest advantage on the MTB. I feel they help by smoothing out power delivery, especially on technical terrain. I think the study using non cyclists is interesting. I think ovals help newer riders pedal in a circle where an experienced rider would already be good at this and therefore giving a bigger improvement to the novice. I also think their benefits go beyond outright performance as there seems to be some evidence of them protecting the knees from injury.

Absolute Black now refer to them as "Traction Rings" and on the MTB, that's how they feel. Changing back to the same tooth count round rings, and it feels much harder in low rpm, high torque situations. I love them on my single speeds, liked them on the 1x11 and probably wouldn't bother on the road bike. SRAM now make an oval ring.

I ride ROTOR Q-rings on my road bike and they are absolutely great. Much smoother pedaling, more becoming one with the bike, less fatigue, more power, quicker recovery.

I rode q rings for a year but did not notice much difference and went back to rounded mainly because of mechanical front derailleur problems. Good video.

This is not data, but I wanted to share my experience. When I started commuting for my first full-time job as a professional, I found that my $100 Raleigh was not that great. My first good quality bike was a 1989 or 1990 Bianchi varsity, purchased new, hybrid 700c bike with straight bars and a supposedly cyclocross frame and biopace crankset. I knew nothing about that or what any of that meant, I just purchased based upon what I was comfortable with and the feel of the brakes. I was a fairly novice not-fit cyclist and scared of commuting with drop-bars due to my inexperience. My ride to work was intense for an hour and I could not stop or I would be late for work. I loved my bike. I commuted frequently and started using the bike for longer distances, often going downtown for evening classes, so my daily distance was getting quite high. I felt like I had tons of power. When the lights turned green, I would race the cars and see how long it was before they would finally catch up to me. I knew nothing about bikes or maintenance or oil or cleaning chains etc. I just loved riding and the bike felt great. Eventually, the chain started skipping. I was told the chain and chainring etc. was worn. After the repair, I did not feel as strong. The mechanic told me that I had "biopace" rings so the new ones might feel different. I asked him to put the same things on that I had before but he said it was a marketing gimmick and was discontinued. I never felt that powerful on a bike again. I felt more weak and my legs felt more easily fatigued for longer rides. I had no training or learning from other people, so maybe biopace rewards novice technique. Anyway, that is my experience, and I would definitely not call it a gimmick for me. I think I had a fairly low cadence at the time, but it is so long ago, not quite sure. I did not use SPDs and never thought about stroke etc. or technique. I just now found out that some old biopace rings are being sold on e-bay. I will likely test them out this summer. I no longer ride with cars (this is Toronto, it is crazy these days) and I am a much older person now, so testing them again would say nothing. I still use that bike. My bike and car is vintage, but so am I.

Well as Froome has just shown by winning the Giro, that they certainly don't hurt your performance.

I was a smaller fit woman when I would ride my then Eight year old sitting on my Blackburn touring rack up a long hill to school. The Bio Pace rings made a noticeable IMPROVEMENT. As I was curious if the bio pace really helped I had my husband switch out to round rings. I found the round rings to deliver noticable less torque with increased knee stress. I rode the round rings for a month then went back to the biopace. They seem to help when riding into head winds too. The biopace tiny mtb inner chainring is almost rhomboid and really helps in mud or loose sand at slow speed. With loaded panniers often helpful. Just my 2 cents.

I have a 1988 Panasonic DX1000 which came with the Shimano Biopace and still love it.

I've been hearing from some pro's I know that it's all about the 'one percenters'. Even a marginal gain is still a gain. And what might be just a marginal gain for a pro could be a big gain for a 'weekend warrior'... Besides the gains on the bike using the Osymetric chainrings as a triathlete I found the run to be easier. Took less time to adjust the cycling legs to running legs and the legs felt fresher resulting overall in a much better total time.

This was pretty helpful I'm a late guest to the party but I enjoy the deeper dive into actual studies.

I like your conclusion saying 'maybe'. Sounds just right. An oval chainring in the practice changes the gear ratio and I would guess (as a layman) that the benefits would also depend on the balance of your muscle groups activation during pedalling. That balance can make up for the 'dead spot' thing, I would guess. I have one of my bikes with oval chainring and my personal perception is that the pedal stroke feels more 'round'. I like the experience. But I haven't yet come to a definitive conclusion comparing to traditional circular rings. I also have not tried different sizes of oval rings to compare them. Currently using 34T on a 11-36 cassette. Another thought: Imagine a world where bikes were invented with oval chainrings and then someone comes up with a circular one, claiming benefits for it... Would it be possible to prove that circular are better (or worse) than oval? Maybe not, maybe there is not a single answer for all cases. So it might be the same the other way round.

Im riding 86 motioncraft 105 groupset biopace chain rings, i love it.

Amount of watts you need to get from point A to B doesnt change regardless what chainring you use, cog you use, crankarm you use, shape of any of these you use so just use the one that makes your pedal strike the most comfortable.

I enjoyed listening to this one as I do all of your videos. Good work and thank you.

One of my bikes has a Shimano BioPace triple chainset. I've been riding it since 1983. It's a touring bike, designed to enable the rider to keep a reasonable cadence when climbing gradients fully-laden. The BioPace cranks are almost in line with the long axis of the oval, whereas the cranks in Bike Fit Adviser's video are at almost 90 degrees to the line of the long axis. The theory Shimano used to promote the BioPace was that the gear was effectively lowered during the hardest phase of the power stroke, allowing the leg to speed through that phase with reduced strain. I'm not sure if practice equates to theory, but when I'm climbing on the BioPace I have the perception that I'm pedaling smoother circles than on a round chainset, and feel less fatigued at the end of a long ride.

I just bought a new bike for the first time since 1995. I will be switching over to round chain rings. My current bike has 105 bio pace on it. So, I have thousands of hours and miles riding "ovals" though not really oval at all. I liked the bio pace climbing more than flat road. high cadence, low power always seemed a bit weird. Climbing you could really feel the torque difference during crank rotation. Just an opinion. :-)

About my experience: I have the oval chainrings, and I noted less fatigue on my legs in long rides. It’s possible perceive some benefits in terms of watts when you push near the anaerobic threshold; with this oval chainring is possible keep for more time the effort in this zone. In my tests I changed the length of the crankset from 172.5 to 175 and with the oval ring I was able to push better the pedals,with less effort,and at the same time have less muscle fatigue.

Interesting, I've always found asymmetric chainrings to be most beneficial for endurance events. Anything over 50km, I feel like I'm less tired with asymmetric and can maintain efforts for much longer than typical chainrings. It only improves times by about 2-3%, but that can be significant when finish times are down to minutes or even seconds.

Here's my $0.02. I tried oval chainrings for about a year and switched back to round primarily because at faster rpm's I experienced a dead spot in the oval rings. I'm talking about 60 - 64 kpm using a 53 x 12 or 11. This is purely my experience. It's possible that some riders start developing power at the very top of the stroke while others develop it later. It's also possible that some riders push through more than others at the bottom of the stroke. I'd like to see some studies that are done using several different types of riders, on a trainer, at different cadences, over different types of terrain, and different distances showing results with a pedal power meter. This study should include at least 30 riders from several different age groups and an equal number of male and female riders. What John described might be the beginning of an inverted bell curve plotted based on experience on x and power development on y; where the most experienced and least experienced riders got the same results. The middle group had mixed results.

My first mountain bike had Biopace. I think I bought it in 1992? Anyway, I used that bike for a few years and wore out the ring, and when I went to replace it I couldn't get Biopace any more. My knees were very painful for several months as I learned to ride on a round ring again.

I ride both recumbent trikes and a plus bike. Will be 60 in June. I have heard that the oval chainrings can be easier on your knees. Just anecdotal, but I am certainly willing to gamble on a purchase and install to know what, if any difference is. Leisure rider, here.

I got the Q-Rings because I was curious and I'm by no means a performance rider, more the casual one and I never had the perfect round pedal stroke, quite the opposite. I feel like the Q-Rings helped with my worst problem: climbing. The upper dead spot of the pedal stroke, always bothered me a lot, it was my weak point and with the Q-Rings this problem vanished completely. At first with Q-rings, on the power stroke I kicked some air until I felt some resistance, but changing the chain ring position made this disappear too. I notice that when I switch to my old school mountainbike that has no oval chain rings, the problem is back. My best friend, usually he's stronger and he has an older model of my bike, I dominate on climbs since I own the Q-Rings. This might be entirely by chance or form of the day, some kind of placebo effect or I don't know what, but I feel that maybe, just maybe, by eliminating my problem with the dead spot of the pedal stroke, it just frees me spending effort in a bad counter reaction to this interruption in flow, which might be a habit that I got because I never learned a perfectly round pedal stroke (I was growing up on Freestyle BMX bikes with platform pedals, you never have a round stroke on them, not in the saddle, not out of it and when you're on a ramp, you just push). Of course this is purely subjective, but maybe you're entirely wrong and it helps the average rider more than the pro who has trained their pedal stroke to perfection. Meanwhile, I have equipped my second road bike with Q-Rings. It may be voodoo, but if it helps me, I'll take it. How come you just speculate and don't try them for yourself with all the methods that you have, like power meter, lactate control and whatnot? Break in time is fairly short, have two rides of about 40 kilometers, adjust them if you feel something's not quite right, have another one or two rides and adjust again if needed. Ride them for like 4 additional rides then switch back to the round ones, see if that makes a noticeable difference and then come back and make a video about it. How about that?

Thanks for the calm delivery. :)

From what I've heard the best benefit is more traction on the MTB and a smoother feeling when pedaling though uneven singletrack.

Thank you for your informative videos and also a BIG thank you for pointing out to the masses the difference between selective (slick) marketing and actual scientific data. With regards to data, I believe that physics trumps all. Any, and I mean ANY, testing, data acquisition, study, experiment, etc. done with a variable component is subject to question at best. Meaning that if there is a human rider operating the physical properties of any object, it's subjective and immediately irrelevant in my book. GMBN does this kind of 'testing' on their site all the time and while entertaining, is merely that. They'll send a rider down a trail and time him on flat pedals, then in clip-less and compare the times in order to determine which platform is faster. The variables involved, even IF you take the human element out of the equation are endless. In the end, all you end up with is what you started out with, one persons opinion. The golf industry put alot of this kind of testing to rest awhile back with the invention of "Iron Byron", a mechanical unit that could swing any club and hit any ball in the with the same force and angle in order to get a sound result for which club could hit a ball farther, and which golf ball flew the farthest. Overnight, marketing took a backseat to a stable, repeatable and objective test. As a result, both clubs and balls became better. Methinks the cycling world could use a robot/mechanical unit to simulate a rider with repeatable, static inputs, to get accurate data on devices like the oval chain ring, powering your up strokes on pedals cs, merely pushing down or rotating in a circular or oval pattern, etc. We shall name him....."Carbon Carl"....

So I am not a born cyclist, in fact I started cycling due to an injury that ruled me out of rowing for a while, but for me the non-round chainrings make a significant difference because of how I am used to applying power. For someone who is great at pedaling circles or has the right kind of pedal stroke it will not make a difference, but since I am used to more or less just mashing my legs down as hard as I can with little regard for any other motion the non-round rings do a very good job of allowing me to apply power in a familiar way.

I came back to cycling to lose weight and doing it for 3 yrs now, I average 12 to 14 mph and once awhile 15 - 16 mph once or twice a year. I get frustrated with my result. I bought an absolute black chainring set 52x36, I got my average went up to 15 - 17 mph at a distance of 20 - 50 miles. Im happy with this chainring and i monitor my cadence instead of speed maintaining 70 rpm minimum to higher. For a weak rider like me its a boost . Burning calorie a 1000 + for every ride.

Due to a long struggle with left knee injury i shifted to rotor Q ring (50/34) setting it up to the recommended position (3 o’clock) my first ride put some pressure on my quads as if i did 1 hour of squats in the gym... did some adjustment by shifting to (4 o’clock position) and my pedal stroke was much smoother and really my dead spots were eliminated comparing to my old setup of round 50/34 chain ring. I wont say that my knee pain was over due to the Q ring however i did go under serious physiotherapy and strengthening exercises and the rotor upgrade gave me that final push to recovery... will i go back to round? I dont think so. Shifting is not as crisp as before but today i got used to it and its been 4 yrs!

Bike Fit Adviser thanks for all the excellent videos you have been putting out. You seem to be pretty much on point on many of your cycling topics IMO. I thought I would chime in on this particular topic since I do have the Rotor QRings fitted on my Trek Madone 5.2 road bike. In my experience I found only a slight advantage over the standard round chainrings and it mostly occured for me while I was cycling in my larger chainring. I also feel that this appreciable difference was when I did longer rides of 50 or more miles at a time. I cycle on average about 150 miles per week and even topped off at around 248 miles a few weeks ago when a century was thrown into my riding mix. So what I will say is these Oval Chainrings will probably be just a marginal gain for most people. You know "Team Sky" talks about marginal gains all the time and when you can have a slight advantage in whatever category, it simply adds up to more positive results. This is probably why Chris Froome still is using the Osymetric chainrings. If science cannot actually prove a clear distinct advantage by using these Oval Chainrings... is it still not worth it for the cyclist having a placebo affect make them feel like a stronger and more efficient cyclist? In my experience my mental attitude can sometimes short change my physical abilities.

I wish a study examined whether oval chainring reduce fatigue/strain over a long ride. Unfortunately most end-points would be subjective and subject to a placebo effect.

If there are clear high effort improvements, that would cover a lot of mountain biking, except for strictly downhill and beginner stuff. If you ride on a regular basis, even light XC rides include climbing and covering soft terrain, which automatically forces a short, high energy expenditure. My worry is that the studies do not have anywhere near a statistically significant dataset. Taking a look at 10 or 20 riders is basically preliminary testing to see if actual research is warranted. Taken alone, it does not prove much.

I comment while i watch the video A 32t oval ring, is actually a 34 when you pedal and 30 in the dead position

I used Snail 36t oval chainring on my hardtail. For me it looks weird because it's not round but it works for me. I do feel that I get some additional pedaling power from the oval chainring..

Have them and love them, both for road, TT and MTB (cross bike will get some soon)

I have a rotor qring, I had a slightly performance increase. I thin the shape not increase the power that you produce but make efficiency pedal stroke. Much more fine style on pedaling while using clipless pedal. Weak muscles of leg were not working because was not worth to work but ovality of ring make easier to pull and kick movement on pedaling so you can put constant power. Mostly the same power but constant so you rise your overall performance.

Compare round and oval wheels on short and long range bike total energy output for short and long km range with the aid of a dynamo test system. Same system has been use to test petroleum cars on rpm and hp output.

I put Shimano Biopace chainrings on my touring bike in 1986. They worked well on the hills. I could tell the difference. I don't have them on any of my bikes today. Froome likes them.

I have a biopace on my 90s specialized allez transition with a Shimano 600EX Arabesque BMX crank matched with Dura-Ace derailers. I personally built and tuned this bicycle after years of riding both round and oval rings. For me it helps on the Steep California climbs helps me keep faster Cadence so that I can gain momentum up the hill without losing stride or getting too tired. In the flat out Sprints it has helped me create that same momentum and serge up to speed. I think it depends highly on whether you keep your bike in a gear or whether you're constantly changing gears. I think these kind of rings from my experience tend to do a better in the higher gears and don't transition from high to low very well due to cross chain deflection. I don't believe these gears are for inexperienced riders due to that fact most inexperienced riders that I know are constantly switching through their gears instead of learning to Pace themselves /transition properly through them or being able to keep the Cadence at the proper RPMs to take full advantage of The Sweet Spot of oval rings. For me I see the most benefit on flats at about 15 mph or higher depending on my Cadence. I see the most benefit in full out Sprint's also I notice a difference being able to keep momentum /decent Cadence up hills. All in all I think it's up to the Rider to decide whether or not it's beneficial for them but with the increasing trend of over-inflated Parts nowadays s*** is so f****** expensive I like the idea of picking up vintage stuff like this and making it work passing guys younger than me on carbon fiber frames that cost 10 times more than my old allez

First of all thank you very much for the great content in your channel. What's your opinion on oval chainrings for knee pain prevention?

It seems, that the difference is that you have usable torque through more percentage of the full circle of pedal motion. Lets say with round ring you can start riding on steep hill with right pedal on 2 to 3 o'clock, and starting with 1 o'clock you cant get moving. Oval ring widens this usable range to, lets say 1 to 4 o'clock. So oval is relevant for steep climbing and very poor terrain, when you may need to push hard at any position of the crank.

Hi, I switched to O-Symetric a month ago , the learning curve was very short, my experience is that I can not ride faster, but I can keep the same power for longer and the high cadance also. ( With this my 1 a week commute of 75 Km is taking me about 5min less) A Colleague of mine tested them also and when't back to round rings as there was no benefit for him. So also I think it's something to do with how you are riding (He is a cyclist for decades and I'm coming from the running world , maybe not so used yet to the round movement) I think it's that personal the only way to know if they will work for you is to test them on several rides approx (500Km ), the only problem here is that it's a bit to expensive !! But hey, if they don't work you always can sell them 2e hand (That was my philosophy when I bought them)

I saw somewhere that your foot doesn't follow a perfect circular pattern when pedaling due to pedal stack height. You'd almost have to write out some engineering dynamic equations to see how that impacts force at each point in the pedal stroke. I might have been able to do that at one time, but it's been way too long. 😁 Good thoughts on the video. I like rotor rings because they feel a little smoother. For about a year, I had them on one bike and not the other. The difference in feel was definately there.

I have been using a ovel chain ring for over a year and there's a definite advantage. How can you tell people if there is or isn't when you haven't used one yourself? I used one on my 2700 mile bike tour with a heavy loaded bike definitely a big help. Try one for your self before giving your opinion.

Interesting video. I have checked oval rings out in the past and remained pretty sceptical, but had never ridden one, and recently needed a new chain ring for my mountain bike, so thought I'd try it out. Went out for the first ride last night and was actually very surprised to notice how smooth the pedal stroke felt Will try it out for a bit longer to make sure it wasn't just 'new bike part joy' before making my mind up for sure though.

Have only a inner Q Ring. It´s a bit easier to spin at high cadence. Riding out of the saddle at steep hills is awesome

Thanks for the video. Although I am thinking of changing to AbsoluteBlack oval for a couple of years, still working with my traditional round chainrings.

I was fairly skeptical to go to Q Rings, I didn't saw the point of spending 200+ on something I didn't even knew it would work. So a buddy of mine handled me a set he had on his house, a 52/36 just like the round rings I had on my bike. From the FIRST ride I saw a difference. My cycling style is a high cadence big chain always kind of style, I felt I could spin even faster and carry more gears without much effort. After two hours I always get some sort of discomfort or cramps but I still haven got none using the Q Rings. So far they work for ME. All I can say is just try them... forget what you see online, experience it yourself and you'll see what it's all about. My friend is still wating for the me to return the Q Rings to him, he will keep wating...

I have Rotor rings on my road bikes and MTB (1X) bikes for several years now. I have them all on position 3 or 2. I find that it alleviates knee pain as I am an older rider. It also helps me maintain power longer and helps on sustained technical climbs special MTB. Am I faster, probably not. But it helps me ride better, for longer. Maybe a wee bit faster.

I love your channel!! There are many good information about cycling!! Thanks. P.S. Every person has each different body types, stamina, etc. so it might not work for everyone just using same materials top pro cyclists use, (even there are many different type of pro...), but the information itself makes me to think and apply for better performance for my cycling workout.

Thank you for sharing all your research into the question with us.

I use the Rotor Oval chainrings on my road bike. I've found out that the pedaling becomes faster, as with my all day bike which has round chainrings.

At lower cadences, often in MTB rides, oval variants modify the effective mechanical advantage so the weaker 'dead spots' sit in an easier zone, i.e. lower gear ratio. Do riders experience a slight variation in pedal velocity? Normal road momentum smooths out this power disparity, but on a stationary trainer it is well-known how irregular a cadence feels, from the power stroke to dead spot. On a marginally doable rough trail climb an oval ring might give a slight assist to keep moving over a rock bar just as you get stuck in the weaker crank position. I adapted fine to BioPace in the 90's, round in the 00's, likely not a consequential factor once you adapt. Chris Froome notwithstanding, he has few imitators in the peloton.

I have full Q on one S-Works and just inner (34) Q on the other. I can swap between the two bikes and not notice any difference. If blindfolded I doubt I could tell. And yet, when I FIRST used Q's I had quad muscle ache for almost a week....go figure...! I like the principle behind oval rings, but do they improve my cycling and / or make me faster? I have no idea.

I've been using Rotor QXL rings for the past 5 years and will never go back to standard ones. Its not for everyone. I felt the difference right away. A few of my riding friends didn't believe me until the have tried it themselves. All of them have oval rings now,lol. Also Adam Hensen from Lotto Suadal said he loves them but can't use them due to his team sponsorship on parts

From our limited testing, we believe the limitations of the body are roughly the same regardless of what style chainring is used. A person can only put out so many watts for a given length of time. If that time is short then the oval chainrings can be moderately beneficial. The longer that time is the less benefit with the ovals. the testing and information you cited seems to support our findings. Good to know.

Had round,had oval went back to round like the wheel,the tyre,the inner tube the cassette,the jockey wheel and bearing,it did feel slightly better on uphill

Bio pace were the opposite orientation to the standard oval and with a more rhombic shape. They put the easy bit on the downstroke and the hard bit through the top and bottom. It was supposed to simulate walking. It was also supposed to ease the knees as the standard oval creates a whiplash action with the knee. Nobody liked it much so that was that.

I have used.rotor.q rings for.about nine years , they work for me , that is all I can say , I would appreciate.that everyone is different and not everyone would get the same results.if you have trouble with your knees they alleviate the problem to a great degree that in itself is a good enough reason to try them , also they can be tailored to variable conditions unlike round rings , suffice to say I would not return to normal rings as I am totally convinced of the superiority of the ovals.

I have an oval on my canyon FS mtb.. And have a circle on my giant hardtail.. I found it easyer to climp on the giant because of the small diameter of the circle of the front gear..

Just from a relatively quick observation, it seems that most of the "studies" done is by using road bikes and mostly at high cadence with the focus being do oval make you faster/ more efficient. I would imagine some of the more scientific studies were done indoors where the bike and rider could be hooked up to various measuring equipment. The most interesting for me are the comments below regarding offroad 1X use especially for tech climbs where more even power and extremely low cadense play a big role. This seems to make sense to me as the power in such situations is far more on/off when one is not "spinning" circles at high rpm. This should be the focus of future studies.

This is obviously subjective but I feel like the oval chainring I put on my single speed mountain bike helps smooth out my pedal stroke on climbs which is especially helpful for maintaining traction on loose conditions. I don’t really notice a huge difference in general though.

I did years back rode the old biopace Shimano c.rings and they where set wrong, turning them, on the crank, was an advantage tho very very slight... Wiggins rode them then went to normal. Froome still rides them..

I have been using Rotor Q Rings for about 4 years. I was having nagging patella tendinitis in both legs and using round rings. In looking around I saw some information about the benefits of the Q Rings for folks with knee issues. It was not a big investment so I switched over to oval and have not had the tendinitis since. I saw no difference in my performance and the learning curve was short.

This is very thorough indeed, and thank you for the time you spent in researching it all. However, I believe what most of us viewers are looking for is really just opinion based on first hand experience. Unfortunately, I've watched several opinion based reviews and I'm still left wondering if it's something I should install. I guess I'll just buy one in the name of science and decide from there. cheers!

It works - period. My legs are not as trashed when I get to a summit of Mt. Diablo. Oval rings just like my field chiropractic - it works - end of the story. 16 years of rididing and racing and after a first ride I can tell a difference.

I got oval chainrings that came on m road bike when I bought it. It is the biopace you talked about and it does feel nice but I don't have a direct comparison to a non-round one on the same bike. However, if you do use one, take your time when indexing, otherwise you will just drop your chain with every shift

Hi is this the same as Bio-pace Chain Rings ? My Myata road bike from the late 1980`s has Bio-pace chain rings.

Great presentation. My question here would be : surely the effectiveness of oval v round depends on the riders' pedalling style. I would love to see research using this as a starting point. Some riders relay heavily on the down stroke. I use a lot of power on the up stroke in a full round-pedalling style. I'd like your views on this. I am, by the way, using Osymetric on my time trial bike but I really don't know if I am benefiting.

ive been riding asymmetric chainring since 2 years now and i find there is a quite big difference actually. and i feel like it fits to a fast fiber muscle like me. maybe not same benefits for slow but powerful muscle fibers

I've put oval to girlfriend's MTB, first thing we did was going to the steep climb that she never could do before as she would spinout... and she mad it all the way up without stopping. so my opinion is that they do work it's just expectations that my be put too high, because of marketing.

Were perfectly able to discern for ourselves for using. What we wanted to learn is what is the range of pedal force through the full revolution of the crank? This no use at all.

It work for me for sure! At least on my mountain bike. Feel really good and natural. I will for sure change my road plates next year, I really feel the difference in the dead spot and feel less stress on my quads. feel better at higher rpm and can spin without the unintended butt bouncing. I dont know if my morphology could be a hint but I have short legs and long torso.

As you say, they've been around forever - I remember when they were heavily advertised sometime in the 80s/90s. So, if they would really bring a significant benefit - wouldn't everybody use them by now? But I've never come across them to try when looking for a bike...

Hey John, Thanks for the video and for mentioning the Biopace rings at the end. I have a TREK 1000 circa 1989 with those exact rings I'm sure. I believe back then the selling point was that this was going to become more or less the standard in cycling and was suggested that as an aspiring tri-athlete these would reduce the risk of knee stress injury. One thing I remember was the chain was much narrower than a round ring chain and; I'm guessing here; the reason for that was the pressure on the pin linkages at the different points of your stroke. I tended to be aware of the slightly odd feel of the crank rotation at first when the bike was a new ride but after a short time (2-6 weeks?) it felt like a well made bike, bottom line. BTW I still have this gem with 90% of the original parts and yes the 1989 chain too. It has ceramic rims that have done me well. Do they still even make that type of rim?

good video, unfortunately no answer but good research. I am kind of waiting for the proof since I see a big difference in my own performance with the oval rings. thanks!

I have Rotor QXL on my high end bike and round chainrings in my other 2 training bikes. The only difference is when sprinting on the flats and climbing out of the saddle. I can use bigger gears when sprinting on either flat roads or hills. Other than that all are the same. You are correct when you say you can only benefit from oval rings if you're racing or strong rider. For the average cyclist no benefit l think.

Truly amazed at how most commenters are missing the point. No one gives a crap whether you "feel" better with the oval ring. This video is about "evidence" proving measurable scientific benefit from oval vs round chainrings. No, there is no solid scientific evidence to support the oval rings being more efficient. If you feel better, enjoy the placebo effect. That one's actually, scientifically proven:)

Don't think for one second there isn't a conflict of interest on this topic Bike shops don't like them, ALWAYS talk about the failed Shimano attempt ... ... and short cyclists don't see anything. It's a tall cyclist benefit, pure and simple. HBC.

BioPace is clocked differently. IMHO this shows a fundamental lack of understanding of this topic.

Great video. good research on the research. I just discovered my Koga Miyata Prologue 1991 has a Shimano Biopace Oval ring and was wondering why it's oval. I'm not a professional, but I do ride in the city everyday.

@Bike Fit Adviser, thank you for posting this. I've checked out your article and many of your videos, and I believe I have a unique question/problem-set. In your opinion or estimation, do you think that one of these non-standard (non-round or eccentric) setups would likely remove (or noticeably minimize) the "pulse" of torque or speed from my riding (1 pulse per downstroke), given that I don't seem to use my calves much, if at all? Seems to me the use of calves lengthens and smooths the effective downstroke, by adding a light push at the beginning and end of it, or perhaps "easing into" and out of the downstroke. Even if it did help, would it be a good option vs calf-strengthening and practicing "better" form? Since I was a kid I have by default ridden with the pedal axle under or just froward of the top of my main arch. Trying to use my calves generally feels very clumsy, so despite watching your vids w/ppl using their calves too much, IDK how I would ensure "proper" form. And which kind of chainring setup might that be? There seem to be opposite set-ups, one that maximizes the pulse and one that minimizes it, and I'm not sure which does which at the moment. I have more details available that I believe would be helpful, like the kind of riding I do, the kind I want to do, and reasoning behind my question, but I'd rather PM or e-mail that. Thank you for your time and input!

I wonder if the oval rings would allow a rider to use slightly longer cranks to get over that TDC issue which I had with longer cranks.

I've wounded how much trouble you would have with your chain ring derailleur with elliptical chain ring.

I’m actually more interested in the subjective research. More interested in how they feel rather than improving time. I’m not a racer, just an almost 50 cyclist with limited experience. Been riding MTB for 4 years and just bought a gravel bike this year. Biggest ride so far is 80 miles so I’m looking at ovals to possibly help a little with endurance.

i’m on 11-28t 105 cassette, what oval teeth should i go with, 52t ? 50t or anything below..i’m on single 105 crank🙏🏼thanks guys!

For decades science told us bumblebees could not fly. Yet every warm day i could go outside and see them fly. It seems bumblebees had not taken the prerequisite aviation engineering courses.

A pertinent question. Do YOU?

Thanks for the overview of studies. It was in 90's first documented, the 1890's! I liked biopace, could get more torque and suited uphills in seat, but had to keep rpm lower compared to round. I would say its very personal thing. Like spinning rather than standing uphill, it can be a benefit, but have to be a good rider to make any performance gains. www.bikeblogordie.com/2016/05/a-short-history-of-elliptical-chainrings.html?m=1

So you say high intensity intervals for oval chainring is good. I think the benefits is for rly high cadence look at Chris Froome (and you go for super high cadens in high intensity efforts) So I would say when you go for big cadenc you pedal in a way it’s harder to work in dead spots so Oval does help you.