Wednesday, August 14, 2013

REVIEW!!! Osymetric Chainrings

Is there any other first picture that would have made sense?
Also one of the few pictures of Froome where he isn't looking directly at his stem...
Those weird chainrings. (Link to the US Site) Hefty claims are made (7-10% more power) and they've shown up underneath the dominant British the last few years (Both Froome and Wiggo rode with yellow on their shoulders and Osy rings. Wiggins also won the Olympic TT on them, however the latest gossip is that he has quit using them, although Froome has continued on with them.) David Millar (a bit of an underground hero to those of us who like to tinker with our bikes) has been spotted on them on and off. And yet, the obvious elephant in the room remains... if they are helping with these dominating performances, why isn't everyone jumping on board.
You can tell I watch Millar's setups.
Now, for those of you who found my blog with a google search of "Osymetric chainrings review" I'm going to be nice to you and give you a quick answer to the question you are undoubtedly scouring the internet for. I don't have the proof that they work. If you want a well conducted "study" I suggest you check out Tom's blog, where he does some real meat and potato testing. (Tom is a smart guy who I make it a point to listen to, so I'm inclined to believe he is right when it comes to the measurements.) So, if all you are looking for is a 100% solid "yes, my watts went up 7% and no other variables were involved" then I'm sorry, no help here. If you care to hear my thoughts however, buckle down and read on.

I know, I just linked you to a blog that pretty much says these things don't work, then agreed with him and told you he knows more than I do about this stuff. So, pretty short blog post huh. Well...yes and no. If it were all that simple, I would most definitely have packed mine back in the box and listed them on ebay... and yet here I am, still riding them and still liking them. And so, the plot thickens... on to my review.
Prelude: Price
Yes, they are expensive. As a niche "competitive" bike part, what else would you expect. At $329 for a set (depending on how good of a shopper you are) I'd almost classify them as "prohibitively expensive." That's a lot of money to spend on rings you aren't sure will even work out for you. That said, fortune favors the bold (and there is a pretty good secondary market for them so you aren't totally out if you decide you don't like them.)
Part 1: Installation
Correctly installed, notice the height of the derailleur.
A bit closer view. Sorry, my Graphic Design professor would have told you I was hopeless with a camera.
The first thing you are going to hear about when it comes to Osymetric rings is that they are a pain in the butt to install and a pain in the butt to get shifting correctly. The former is a bit bike (and more specifically your front derailleur mount) dependent and the latter is just plain false, at least on a TT bike.

That said, it was a bit of work to get them installed on my Planet X. The Front Derailleur being brazed on presented a challenge in itself. The large chainring (a 56t, probably too big for me, but hey it has worked out fine so far.) would not clear the front derailleur even with the included spacers (which push the FD farther back.) This is almost certainly not a problem with any chainring except the 56t, but it is an issue. The solution was fortunately pretty simple. I removed the Derailleur hanger and dremeled some extra space to mount it higher on the frames braze on. I've also seen a different riser block for sale that solves the problem by letting you mount the FD higher up (if you aren't into modifying your bike) if you don't mind spending some extra cash. If you had a clamp on FD this problem is obviously moot since you have all the room in the world to play with.
Frontal view of the FD/catcher.
Once the rings were on and the necessary clearance was gained, it was just a matter of setting the derailleur up correctly. I don't see what the big gripe here is... just take your time and set the derailleur up correctly and it should work fine. Most people's problem with this stuff is they just don't take the time to get the FD lined up and spaced right. You may need to add the little (included) spacer to widen the FD cage, but that's simple stuff and should get you the space needed to reach most gear combos. (even the one's you shouldn't be in, although extreme cross chaining is will still result in a grind... shame on you for being in that gear anyways)

Anyways, for the moderately proficient wrench these should not be a problem to install.

Part 2: The Ride
My last TT warmup on the Osy's. I had a great ride.
When it comes down to it, this is the part that is most important. (IMO) How is the ride? Well, from my n=1 experience, it's great. Most people say it takes 2-3 good rides to get used to the rings... for me it felt natural almost immediately (seriously, like 30" into the first ride I felt "normal") of course this could be due to the fact that I've always been a masher, especially when it comes to my tri bike. I assume that the more you "spin" the more awkward it is and the longer it would take to be natural, but for somebody like me who has always felt best at a mid-80's cadence...well, it was awesome.

--- Warning: This next been is HIGHLY subject to Placebo effect and Variance ---

The first "real" trainer ride I did on them I set two new power records (5' and 40') both of which were around 5-7% higher than the previous records. Now, here's the disclaimer... It's been a while since I had rode 5' sets at a high power %, so most likely I would have been faster on any rings. (the 40' record is also not a good indicator as I normally don't try for "40min" power records) Nonetheless, it did feel good to put down a new record on them. Obviously there's also the "this makes you faster" effect, which in turn can convince the (weak?) mind that you can push harder... whatever. Science is for some people, but I'm a romantic.

--- End of questionable n=1 ---

Still, that's not what sold me on keeping the rings. I like them because of how they feel while I'm in aero. It's tough to describe, but I simply feel like I have an easier time breathing on these things. Again, this could be in my head, but historically I have a hardish time staying in aero on 110% + sets on the trainer for the whole set. I just have a hard time getting the oxygen. Once I started using these things, bingo, staying down for every set, no problem. Could just be a fitness thing... (although that doesn't seem likely) could be pixie dust, could be Osymetric Chainrings. Whatever it is, I like it.

The one "flaw" to the rings is that the shifting is not "crisp" like you are likely used to. No pins, no ramps, just metal. Personally, I haven't had any trouble shifting from big to small (I do - and it's recommended - to run a chain catcher... but that's just a good idea anyways) at all, and the only trouble I ever have going from small to big is when I am pedaling through the shift and not "clutching" (backing off) for the shift. I've still always had it make the shift, but it sounds like hell doing it. In most TT's / tri's it's not much of an issue as I'm almost always in my big chainring, but it's something to consider. (and plan around)

Final thoughts:
Nothing witty to say here... I just always thought the "Wiggo Punch" was a cool end to the 2012 Tour. Oh he was riding Osymetrics too... so I guess that is sort of relevant. Kinda.
THIS is good for extended reading if you haven't already been through it. It's basically going to tell you what everything else on the interwebs will tell you... do they work? We aren't totally sure. Most sources agree that they "may" benefit certain riders, and that they "probably" don't hurt... so unfortunately... we're still floating in the same boat. For me, personally, I'm going to continue using mine. I'm also on the fence about getting a set for use on (one of) my road bikes. On the one hand, I really, REALLY like my Wickwerks (review here) rings, but I really like the way these things feel. I suppose trying them on Indexed front shifting is the next step. (I have my reservations about it, but it could be unfounded.)

So, much like saddles, aerobar bends, doubletap / sti shifting and many other things in cycling, a lot of whether these things will work well or not for YOU depends on YOU. For me, they're staying on my TT bike from now on, and I'm at least going to consider them on future road builds.

Thanks for reading, let me know if you had any experience with them.

Another road race/crit for me this weekend, and then an Olympic (possibly my last race this season) the week after. Hopefully it'll all go smoothly :)

Keep the rubber down and ride hard
-Christopher Morelock
*PS - FTP Test last night. 20' Power was 307watts! Hoping I can muster a 300watt FTP by next season.


  1. I use them on my (road) race bike, and love how they feel when you are really on the rivet. That said, they shift poorly under load, even with Di2. The time when you most notice it is when you are cresting a climb and need to go to the big ring to push over the top. Don't even think about trying to shift at 400w.

    I have Rotor Qs on another bike, and with the aero (ie. heavier and stiffer) outer ring, they shift well with Di2. The Q rings don't come on/off the power quite as dramatically, which feels a bit better for those with high cadence.

    Another small issue with the Osymetrics is the noise. You are dropping 4 chain pins simultaneously on the flat part of the ring, and that makes a noise 2x per pedal rotation. It just sounds like your gears are poorly adjusted, and it can get annoying on a long climb (it is worse in the small ring).

    I think for a TT application, these rings are great. Shifting rarely happens, and with the tight hip angle, you cannot generate much power over the top. That said, I have Q rings on my TT bike because you can adjust the timing of the power stroke to accommodate the steeper seat tube and more forward hip to BB relationship. This did not seem to bother Wiggo or Froome, though they have UCI limits on positioning, so they are not as far forward as a triathlete might be.

    Interestingly, Rotor released the QXL recently, which is more exaggerated and probably close to the Osymetrics in terms of the change in gearing.

    I wish that Osymetric would have Wickwerx or Praxis make the rings for them and put in some shift ramps and pins, and make them a bit stiffer. That would go a long way towards improving the shifting performance.

    Biomechanically, the concept just makes sense to me, but the studies don't seem to bear this out. I guess it comes down to feel, as you say.

    1. Did you use the new (thicker) Osy's or the older ones. It's possible the newer ones shift better with Di2, although I have no idea (having the older rings and mechanical haha)

      They do sound a bit rough don't they...

      Have you tried reverse mounting the Osy's, like the "optimal" position in the study shows... I just did that and it seemed to help the "feel" of coming over the top.

      Holy crap if they had wickwerx ramp/pins these things would be nuts!

      It makes sense to me that if we believe that everyone basically just ends up mashing when making power (that is, none of this "scraping" business on the back of the pedalstroke) then having a bigger gear there and a lower gear in the "recovery" should be better. Although as you say, the studies don't seem to prove it.

  2. Not sure why it has me as anonymous using my Google ID. more issue of note.

    My experience has been that the non-round rings mess with crank-based powermeters. The Quarq with the Osymetrics, calibrated by Quarq, reads significantly (~5%) higher than my Quarq with round rings. I have been testing Vector pedals as a constant between the two bikes, and they agree with the round rings. This may be an ANT+ issue, as it only sends a power reading every second, or 1.5 pedal strokes. In that time, your power is pretty variable on a non-round ring.

    When they transition to Bluetooth, which can take multiple readings per second, hopefully we get better numbers.

    1. yeah, I've heard multiple reports of crank based power meters reading high. All the science on that is a bit above my head, although Tom talks about it on his blog. I use a powertap so it shouldn't be interfering there.

  3. Osymetric USA has ramped and pinned rings for he new 4 arm Shimano DA 9000, and Ultegra 6800

    1. I saw that, wonder if those of us stuck in the old days will get some trickle down in the future.

  4. You mentioned having hit new power PRs using rings. I have read that power runs higher on the osymetric rings. Have you noticed speed and RPM stay the same with the 7% increase in power? Or has speed and RPM increased as well.
    Thanks for the review!

    1. Basically the power will run higher on a crank based system. (srm/quarq/etc) It shouldn't matter on a Powertap due to the power being measured at the hub.
      Cadence is fairly close but a little lower (I was in the 80-85 range even before switching though)

      As far as the PR's go... considering I'm riding consistently and have stayed healthy/on plan, I suspect I would have hit new PR's using any rings... or at least I would have expected to.

      Hope that helps :)

  5. They COULD affect the PT on a trainer if the flywheel inertia isn't high enough though...for the same reasons the crank based PMs are affected in high inertia environments. Sort of the flip side of the same coin...the constant rotational velocity assumption being the culprit. If you hear the rear wheelspeed varying during your trainer rides ("whoosh, whoosh, etc.") then I would bet the PT is reading high.

    1. Hmm, I think I follow you, for us laymans... spinning the wheel "uneven" (due to the shape of the rings and lack of proper tension on a trainer) would create something similar to the effect of Osy's on a crank based system?

      Although if you have your trainer mis-adjusted I'd think you'd be getting shotty information regardless.