Have we done Oval chainrings yet?

I saw this earlier, I didn’t realise they were coming to mountain bikes, I was tempted to try them on my roadie but couldn’t find any at a “reasonable” price…
http://absoluteblack.cc/oval-104bcd-chainring.html

Soooo….anyone got one? Is it the best thing since sliced bread / clutch mechs? Or another flash in the pan…?

One of the technologies which gets a resurgence every now and again.

Plenty of roadies use them.

http://en.wikipedia.org/wiki/Biopace

Great on my single speed- goldtec do one called the One key- different than bio pace- do a search on taxzys wonky rings

They didnt catch on that well back in 89 (or there abouts)I had one and got rid fairly quickly, just didnt like it……If you have a nice pedal action then you do not need an oval ring!

taxzys wonky rings

“tazzy’s wonky rings” might get you there quicker!

Don’t know that it really made a huge difference , when I had them OEM , on my then brand new ,Raleigh Avanti mtb in 1987.

I’ve just borrowed one so I’ll see what it’s like. Had to go up 2 teeth on the singlespeed so I’ll see if I can still get up some of the hills.

i thought biopace got it wrong, and these are essentially the opposite of that

Got Taz’s wonky rings on my bike – Goldtech variety – they are great on SS bikes, so much better than Biopace ever were.

There’ve been a few narrow-wide oval chainrings, they don’t work with shimano mechs though, the slight chain growth means the clutch gets worked much harder than a round ring and adds resistance and wears out.

Had them on my first mountainbike in 1985, they didn’t catch on.

Have we done Oval chainrings yet?

About 25 years ago.

I think I can almost buy the snake oil for road use where power input is a lot more consistent – but on an MTB where power input is a lot more choppy I don’t see how much they can help..

I’ve got Rotor rings on two road bikes and my mountain bike, I think they make a difference. I’ve got a 15 mile road loop I do most evenings, the first time I did it using oval rings I went round about two minutes quicker. Over the course of a month I tried round and oval rings on a variety of local loops and each one was faster on the oval rings.

Better riders than me seem to rate them. Carlos Sastre won the Tour using Rotors, Bradley Wiggins did his win on Osymetrics and plenty of other pros use them.

Huge fan of the Goldtec OneKey here. I have 5 on back order 🙂

The big question for me here is why are you faster? Someone with a power meter needs to go investigate if they really do magic out some more power.

All the naysayers are right they are rubbish cus bio pace was – tbh if you try one you may like it or not but really to offer an opinion I would suggest you try one especially if you ride singlespeed

Dave’s been using Rotors for a few year, he know his stuff and is quite good a riding a bike too 😀

http://www.davebuchanan.co.uk/the-kit/

My brother in law rides with Rotor Rings[/url] instantly he seemed to cruise up the hills. They seem pricey but the difference might be worth the £’s. I think the cervelo teams ride with them, spotted them on the tour.

The big question for me here is why are you faster? Someone with a power meter needs to go investigate if they really do magic out some more power.

I had this debate/argument with someone (probably Tazzy) on another thread. IIRC there were two theories put forward, If you think about it in terms of impulses (force*time) then it does improve things. If you imagine the pedal stroke simplified as 4 segments of force X for 90deg x2 and 0 force for 2x 90deg, then the chain moves at a constant velocity then by using wonky rings you lengthen the time the pedals are being pushed on and shorten the dead time so force x time is greater. So your legs can do more work without having to have bigger muscles. It doesn’t give you extra cardiovascular fitness though, so for longer efforts there has to be another explanation. Which is there if you look at the usual advice given that you pick a chainring a few teeth bigger than your current round ring so that the bit your matching is the smallest part of the chainring (i.e. 32t round = 34t wonky). So for the same speed/gear you’re going to drop your cadence slightly, which is a common method of unloading your cardio system.

The other theory is simpler, big muscles push down on the pedals, small muscles get you past TDC, the bigger muscles are far more efficient so anything that makes life easy on the smaller muscles is going to increase your power output.

Interesting points! I think I’ll try the road ones first as the pedalling is more even/ constant than off road… Anyone seen any cheap lately that cares to share?

As per my previous post, I’m a huge fan of the Onekey on my singlespeed. However, I don’t agree with the theory that you can go with a bigger oval chainring than your usual round one and get free speed/power. I originally replaced a regular 32T with a Onekey 33T and, whilst I instantly liked it, I still felt like I was pushing a bigger gear, albeit more smoothly. To compensate (when I’m riding in the hills), I’ve dropped from an 18 to a 19 sprocket, which works great for me.

The main thing I notice with the Onekey is a smoother pedal stroke. Two other experienced singlespeeders have tried mine out and immediately noticed the same thing. Whether that translates to “moar speed” is debatable, but it sure does feel nice to ride :-).

I think I can almost buy the snake oil for road use where power input is a lot more consistent – but on an MTB where power input is a lot more choppy I don’t see how much they can help..

On the choppy SS MTB is exactly where I think they do help. As PH says above, they seem to help me keep a smoother power output on low rpm climbs. I replaced a 32T round with a 34T oval SS ring and find it’s no harder on climbs until I get to near-stalling speed and the added 2T helps on spinnier sections. There’s no free power gains imo, just an efficient output that feels more natural.

On a geared bike with closer ratios I’m not sure the oval rings do much that simply being in the right gear can’t do, but the logic in pedaling efficiency must still apply. I just don’t notice it as much when riding gears on the back, probably as I spend less time hauling up climbs and more time at a more normal cadence.

This ^^^ I experienced just that effect when I swapped, running a 34 Onekey and a 19 on the back on my SS.

It was your fault I got one, James! 🙂

We shouldn’t confuse things here, there is no “theory or concept”, this is proven science, fact.
I think most people who are sceptical simply haven’t tried them.

I think you only have to look at Marianne Vos, she’s on Rotor Q rings. Rui Costa, World Champion, on Q rings. Anyone watch the Tour of Britain?
Winner, Dylan Van Baarle, on Q-rings.

Vos in particular is sponsered by Shimano, but removes the round rings and puts the Q rings on the Dura Ace cranks.

Christie O’Hara produced a brilliant peer reviewed study in 2011 from a US University, this is science, not a theory, it’s proven. Round rings do not optimise the way humans produce power.

How does this relate to MTB? Look at the Vauxhall Mountain-Trax team, very successful, Tim Dunford another very successful rider, Dave Buchanon. The list goes on. These guys aren’t paid to ride this stuff, they choose it as it gives them a clear advantage. Q-rings work really well in an MTB set-up, brilliant for climbing, recovery and also grip.

I think people should try them before dismissing them.

We shouldn’t confuse things here, there is no “theory or concept”, this is proven science, fact.

Is it? Where is the science? Have you got that Christie O’Hara paper? Why are they not universally adopted if they’re that much better?

A list of people who’ve won whilst using them doesn’t count. You could say the same about SRAM groupsets or Zipp wheels or whatever.

Look at the Vauxhall Mountain-Trax team, very successful, Tim Dunford

With all due respect to the guys, and I’m friends with Ben/Isaac/Tim so I’m sure they won’t mind me saying, they’re not exactly dominating are they (Tim wins marathons, but he won marathons on round rings). They get beaten by folk using round rings, does that not make round ones better…?

Edit: FWIW I do believe there’s quite probably an advantage. But you’ll not convince the naysayers with a Ron Burgandy-esque “they’ve done studies, it’s science” argument.

I wouldn’t rely on pros riding them as proven science that they work – pro riders are well known to be as gullible for this sort of thing as anybody.

However I do also expect there may be some real advantage. The thing is we’re talking about utilising the human body here which isn’t the perfect machine, and the theories given make plausible physiological sense.

I just want Goldtec to make some track size One-Keys 🙂 144 bcd 48, 49 and 50 would be great thanks…

greenstix7 – Member

We shouldn’t confuse things here, there is no “theory or concept”, this is proven science, fact.
I think most people who are sceptical simply haven’t tried them.

I think you only have to look at Marianne Vos, she’s on Rotor Q rings. Rui Costa, World Champion, on Q rings. Anyone watch the Tour of Britain?
Winner, Dylan Van Baarle, on Q-rings.

Vos in particular is sponsered by Shimano, but removes the round rings and puts the Q rings on the Dura Ace cranks.

Christie O’Hara produced a brilliant peer reviewed study in 2011 from a US University, this is science, not a theory, it’s proven. Round rings do not optimise the way humans produce power.

How does this relate to MTB? Look at the Vauxhall Mountain-Trax team, very successful, Tim Dunford another very successful rider, Dave Buchanon. The list goes on. These guys aren’t paid to ride this stuff, they choose it as it gives them a clear advantage. Q-rings work really well in an MTB set-up, brilliant for climbing, recovery and also grip.

I think people should try them before dismissing them.
Posted 5 minutes ago #

I agree about trying them but the fact some spotrs people wear them doesn’t matter.
A lot of sports people wear that brightly coloured tape, those little wrist bands which contain magnets or holograms 😆 etc.

Awesome, just seen they are now doing them – ordered…

hmmm… i’m in the process of refreshing my drive train right now… this thread is of interest…

would be great to hear to real world reviews

I’ve had the Tazzy snake-oil one for about 18 months.
Great on the SS, seems to even out the pedal stroke.

I tried Taz’s wonky ring and just couldn’t get on with it, felt weird like something was broken. Back to normal ring now

Sam – BETD’s site will always show them as in-stock, even when they’re not ;-). Last I spoke to them a few weeks back was that they should be ready soon though.

The article is here.

http://www.pelotonmagazine-digital.com/pelotonmagazine/september_2014?pg=59#pg59

http://www.pelotonmagazine-digital.com/pelotonmagazine/september_2014?pg=59#pg59

Great quote from the last paragraph.

Q rings feel rounder than a round ring so i don’t get the “they felt weird” They totally smooth your pedal stroke out.

It’s significant that the top athletes choose to use them, they are the ones looking for any advantage. A q ring can lower your heart rate by up to 2 bpm, no big deal? Over a 3 week race it is a huge help.

An oval ring surely doesn’t generate any more power than an equivalent round ring… but net power (as measured by every PM except the new Rotors) perhaps yes on the basis that what you are actually potentially improving is pedaling efficiency, i.e. reducing the amount of time one leg is working against the other. Only someone with a all singing all dancing Rotor PM would be able to tell you if the oval rings make any difference IMO and all of this is dependent on the individual’s initial pedaling action anyway. I don’t think it is true to say an oval ring increases the time of the down stroke since the time you spend generating useful power throughout the stroke will be dependent on how that individual uses the muscles and joints of the lower limb to generate power.

Basically, my feeling is they are a bit of a crutch for poor technique. I see it a bit like a knee brace which is also a controversial thing in the orthopaedic world. Yes you can show the science that they work but the mechanism of them working is something mechanical replacing the job of lazy muscles. Probably a crutch most of us could benefit from but probably also not the only way to get the same gains in pedaling efficiency. Does something mechanical replacing some muscle activity guarantee reduced energy required overall and therefore more speed as a whole for less effort- not necessarily and although the idea is certainly plausible I am yet to see anything conclusive.

The Vauxhall Mountain-Trax team may use them but they are also a collection of very fast and talented guys/ gals who sometimes win stuff and sometimes don’t. Vos may use them but she is also supremely talented. She would win with a square ring 😉

I’d like to try them but I would imagine the difference to riding output is small at best, rather than “a significant advantage” as others describe here… I think the claims are slightly overstated but O-Hara’s take home message is no-one is at a disadvantage with an oval ring and gains are in the 1-6% power range. Sounds significant for racing but scientifically this is well within measurement error, inter-subject variability, day to day variability, etc.

I’d disagree with regarding the Rotor PM. The true test would be a Power Tap. One of the reasons certain power meters over-read when fitted with oval rings is that they use a magnet to calculate cadence and assume a constant velocity through the pedal stroke which doesn’t happen when you’re using oval rings. Any PM using an accelerometer should give an accurate reading.

Yes that is actually a good point monkeyfudger. So, in truth perhaps a force measuring crank on the left and right side set up for measuring everything independently from assumptions commercial PM’s generally use is the only way to really get any idea. A Powertap may be slightly better but you are still only measuring net power produced not actual power developed by each leg where there may be short durations of one leg working against the other (thus decreasing efficiency) which I would imagine is one of the likely advantages of an oval ring.

Seeing as how some teams look for any advantage, Team Sky for sure, if oval rings are obviously ‘better’ then all their riders would be using them. Wiggo was but stopped using them and I don’t think went back to them did he? So not clear cut at all.