I do a lot of trail riding and have heard a lot of good things about oval chainrings. I want to try one out, but they are very expensive and if I am going to invest in one, I want it to be of good quality. The one I want to get is the Direct mount oval chainring by Wolftooth. I just wanted to hear more peoples opinions on if it is a good investment before I make the purchase. Any experiences or thoughs on if it lives up to the tale, ya know?
There is no data to suggest an oval chainring is more efficient or generates more power.
It may make sense “intuitively”, but data doesn’t back up the intuition.
Save your money.
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I personally love them because I like weird things and it does provide a better pedaling sensation. I have not witnessed anything that leads me to believe they increase power or efficiency. However, if you do swap between bikes with oval and round, it’ll feel weird as hell.
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If you want to use one because it looks cool or you like trying different stuff go for it. But there is no evidence of it helping you perform better.
The only way to truly make it work is if you have shorter cranks, like 145 or something, whatever the cool kids are doing.
Surprised this is still a thing, it was “in” back in 2018 maybe? I can’t quite remember…but, once my compression boots come off and I finish my ice bath, I might have a better idea.
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I had some of the Shimano Biopace oval chainrings in the late 1980s. Shimano 600 groupset.
I don’t have an urge to use a modern version of the idea.
But, if you want to try oval chainrings, go for it.
From what I have seen of Wolftooth, it is decent quality stuff.
To my knowledge, there is no performance benefit, but some riders prefer the feel. E. g. I have 165 mm cranks on my road bike and 175 mm cranks on my mountain bike. Pedaling on my mountain bike felt like pedaling in clown shoes, very uneven. Oval chain rings feel more comfortable. I am partial to Rotor’s chain rings. Pity they don’t make stuff for my XTR M9000 1x cranks anymore. (That’s also the reason why I didn’t get new cranks, they are functionally perfect …)
I’ve heard one buddy say that oval rings will “split the difference” between tooth counts; ie, a 36 oval will be the effective equivalent of a 37 tooth.
He also says your suspension pressure should ALWAYS be your body weight minus some number…
Biopace was horrid….but to be fair, it was a different concept to most oval chainrings.
Biopace sought to “equalize” the supposed inefficiency on your pedal stroke by ovalizing the dead spot area of the chainring. Today’s oval chainrings seek to increase the leverage of your pedal stroke during the downstroke.
180* difference in terms of application.
There were some others around at about the same time. Not as common to see as biopace. IIRC there was one from SR and another called Cycloide or something like that.
I didn’t notice a diff pedaling my mtb with Biopace vs my road bike without, but just looking at the Biopace rings, they didn’t have much eccentricity. The phase wrt the crank was almost 90 degrees off what’s used nowadays.
I found this page on sheldonbrown.com
As well as identifying the two systems I vaguely recalled from biopace days (SR Ovaltech and Sugino Cycloid) it refers to eliptical chainwheels going back to the turn of the century (the page was written in 1995!) that were phased wrt the crank as per the nowadays version.
The article concludes “Ever since the chain driven bicycle was invented, elliptical chainwheels have been re-invented and re-abandoned for the same reason every ten or fifteen years.”
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What are the benefits you’ve heard about? I ride MTB a lot, and none of the people I ride with have oval chainrings. Not saying they are without merit - whatever works for you - but if they had that much merit, more people would be riding them, and OEMs would probably spec them as at least an option on some bikes.
One possible benefit I could see is when riding uphill on steep technical terrain, where you need to surge to get over a ledge or root. If the chainring is oriented in the right way, it could increase the resistance of the pedal stroke as you approach the 4 o clock pedaling position, and maybe mitigate the “over pedaling” sensation that can happen in situations like that*. But that’s me just speculating, I’ve no idea if this helps in practice.
Note: * the current solution in this situation is just downshift one cog
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Oh yeah…the concept and product has been around for literally over a century. There is nothing new of novel in the idea of oval chainrings.
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Go for it! Just don’t seem surprised when you start dropping your chain often. Oval and MTBing don’t lead to good chain retention.