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  1. #1
    Join Date
    Oct 2003
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    The 802
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    245

    Oval Narrow/Wide - anybody got one?

    Looking to finally go single ring on my Intense this spring. I'm thinking of trying a 34T oval narrow/wide. The only one I know of is from Rotor. Anybody tried it? Anybody know of any other options?

  2. #2
    Join Date
    May 2008
    Location
    SLC
    Posts
    358
    I just picked up a chinese knockoff from ebay. I haven't tried it yet. $.99 plus $12 for shipping. Figured it was worth a shot.

  3. #3
    Join Date
    Apr 2008
    Location
    Virgina (It's humid here)
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    4,496
    I've been looking at this. Direct mount for X9 GXP crankset.

    http://www.amazon.com/B-Labs-Bionico...nring+oval+28t

  4. #4
    Join Date
    Nov 2005
    Posts
    2,833
    I have ridden the Rotor briefly and I liked it quite well. Can't compare with the other options, but that one worked nicely, at least for my pedaling stroke. I used it in the middle of the three positions, never tried rotating it.

    I have a knee that's driving me to considering shorter crank arms and I might grab one of those instead--or first, at least. They talk it up for high cadence, and it felt fine there, but for me the big plus was very low cadence/high torque, because it noticeably reduced the peak torque required to turn the pedal over at the top of the stroke. Obviously that gets made up 90 degrees later, but I found that part barely noticeable.

  5. #5
    Join Date
    Oct 2001
    Posts
    7,594
    Quote Originally Posted by epic View Post
    Looking to finally go single ring on my Intense this spring. I'm thinking of trying a 34T oval narrow/wide. The only one I know of is from Rotor. Anybody tried it? Anybody know of any other options?
    Yeah currently I have a Rotor CX1 44T ring on my SSCX and a B-Labs 36T Oval N/W on my 1x11 29er race hardtail.

    I'm a big fan of both. I tend to notice the effects of the ring mostly when I run them on singlespeeds but that is to be expected I guess.

    In my experience Rotor rings tend to wear faster than I would like, but the B-Labs gives me hope that it will last longer. I don't have many miles on it yet, but it at least appears that there is a lot more material in the ring.

    The US Distributor for B-Labs is based in the Reno area. I have his email and if you have any questions he is super responsive and ships things quick. PM me if you'd like it.
    Waste your time, read my crap, at:
    One Gear, Two Planks

  6. #6
    Join Date
    Jun 2004
    Location
    Pemberton, BC
    Posts
    1,453
    I had a Biopace ring in the late 1980's. It was the shit, or just shit, cant really remember.

  7. #7
    Join Date
    Oct 2002
    Location
    Shadynasty's Jazz Club
    Posts
    8,254
    Quote Originally Posted by xyz View Post
    I had a Biopace ring in the late 1980's. It was the shit, or just shit, cant really remember.
    Somebody rotated their Biopace rings a couple holes and invented something completely new! Sheldon Brown was a Biopace believer, maybe there's something to it.
    Remind me. We'll send him a red cap and a Speedo.

  8. #8
    Join Date
    Dec 2005
    Location
    Front Range, CO
    Posts
    591
    check out Absolute Black rings. Much cheaper than rotor. I haven't used them but generally positive reviews if you're into the oval thing. Lots of interwebs reviews and long mtbr threads on them like this one http://forums.mtbr.com/singlespeed/o...ed-932469.html

  9. #9
    Join Date
    Oct 2001
    Posts
    7,594
    Quote Originally Posted by bagtagley View Post
    Somebody rotated their Biopace rings a couple holes and invented something completely new!.
    Pretty much.

    FWIW, when I got my first Rotor oval ring a few years ago, I mounted it backwards. And indeed, it had the opposite effect, and it was terrible. Definitely made things much harder. So then when I swapped back to the correct way, bam....nice.
    Waste your time, read my crap, at:
    One Gear, Two Planks

  10. #10
    Join Date
    May 2012
    Location
    san diego
    Posts
    1,532
    Quote Originally Posted by bagtagley View Post
    Somebody rotated their Biopace rings a couple holes and invented something completely new! Sheldon Brown was a Biopace believer, maybe there's something to it.
    Local guy I know just put the Absolute black ring on his bike. Seems to like it so far. According to their site biopace had the oval shape oriented the wrong way which made it harder to pedal. The AB ring has the narrow part delivering power when you are at the weakest (top) part of the pedal stroke and the widest part delivering power during the most powerful part of the pedal stroke. See "word on Biopace" http://absoluteblack.cc/oval-104bcd-chainring.html. Seems to make sense. I might try one of these next time I need a ring. Not much more than the last ring I bought.

  11. #11
    Join Date
    Feb 2006
    Posts
    6,046
    I wonder how one of these would work with a shorter crank (165mm or 170mm) for all around trail riding, vs. your standard 175mm?

  12. #12
    Join Date
    Feb 2006
    Posts
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    I thought a bit more about this while riding yesterday. I've ridden clipless exclusively (including racing DH) for about 20 years, and have a pretty well refined circular pedal stroke, meaning that I pull back and push forward when the crank is vertical and don't mash in the mid-stroke. I'm also a very good technical climber and have ridden long travel FSR bikes for years, both things that benefit from a consistant stroke. I'm guessing that I would benefit less from these oval rings, but they are used by road riders who have a refined stroke and ride clipless, sooo....?

    http://www.roadbikerider.com/cycling...-pedal-strokes

    Another way to get feedback is to ride a mountain bike up a steep hill with a loose, gravely surface. If you pedal jerkily, pushing down hard, you'll lose rear-wheel traction. The tire will spin abruptly on the loose gravel, causing you to lose momentum and put a foot down. But if you concentrate on pedaling evenly through the whole 360-degree circle, the rear wheel won't lose traction.

    Interestingly, said Broker, among all the riders tested over the years at the U.S. Olympic Training Center in Colorado Springs, mountain bikers had the smoothest pedal stroke, even smoother than pursuit specialists on the track. Off-road legend John Tomac was the smoothest of all.
    Last edited by Damian Sanders; 06-04-2015 at 07:41 AM.

  13. #13
    Join Date
    Apr 2008
    Location
    Virgina (It's humid here)
    Posts
    4,496
    Interesting perspective. I'm going in the opposite direction. I just switched to flats about a month ago because of a year long knee problem. The knee is responding well to the change, but my shins are suffering dearly!
    Since I'm still in the tentative stage of the transition, I'm a bit concerned that the oval will fuck things up enough to set me back from the little progress I've made.
    With Shimano's new XT 11 speed drivetrain parts coming out soon though, I'm getting ready to drop a few hundo on my drivetrain, so this would be a logical time to go Oval.

  14. #14
    Join Date
    Oct 2007
    Location
    Happy Valley, CO
    Posts
    378
    Getting the wolftooth 32t oval mounted right now. will give feedback after a few rides!
    "Last one to the bottom is a Coward"

  15. #15
    Join Date
    Nov 2005
    Posts
    2,833
    Quote Originally Posted by Damian Sanders View Post
    I'm also a very good technical climber and have ridden long travel FSR bikes for years, both things that benefit from a consistant stroke. I'm guessing that I would benefit less from these oval rings, but they are used by road riders who have a refined stroke and ride clipless, sooo....?

    http://www.roadbikerider.com/cycling...-pedal-strokes
    It's easy to feel yourself pushing fore and aft on the pedals when the crank crosses vertical, but if you quantify that and compare it with the force applied mid-stroke you'll notice that even a comparatively circular pedal stroke goes almost to zero torque at top dead center. It's not at all like turning a crank using your arm/hand. Even with a "circular" stroke you'll still notice and probably benefit.

    Trying to avoid full geek mode...the torque vs crank angle is commonly accepted to approach a sine wave whose average is half its peak as a rider gets more efficient. If that's accurate (the research goes back to the 1890's, but one study from Japan seems to have the best evidence for correlating efficiency with sinusoidal torque) then even the optimal pedal stroke for an experienced rider falls very close to zero across top dead center. Mountain bikers have a lot more incentive to even out our torque, whether from traction or suspension bob, but we're not going to change it by all that much.

  16. #16
    Join Date
    Sep 2008
    Location
    Sweden
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    253
    Quote Originally Posted by alewi11 View Post
    I just picked up a chinese knockoff from ebay. I haven't tried it yet. $.99 plus $12 for shipping. Figured it was worth a shot.
    Care to share that link?

  17. #17
    Join Date
    Feb 2006
    Posts
    6,046
    Quote Originally Posted by jono View Post
    It's easy to feel yourself pushing fore and aft on the pedals when the crank crosses vertical, but if you quantify that and compare it with the force applied mid-stroke you'll notice that even a comparatively circular pedal stroke goes almost to zero torque at top dead center. It's not at all like turning a crank using your arm/hand. Even with a "circular" stroke you'll still notice and probably benefit.
    No, I actually have a pretty well refined circular stroke where I'm producing good power with the cranks vertical, while not mashing in the lower part of the downstroke. I pedal seated 90%+ of the time. While it may not be the most efficient or powerful stroke, it works well for technical riding.

  18. #18
    Join Date
    Nov 2005
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    2,833
    Quote Originally Posted by Damian Sanders View Post
    No, I actually have a pretty well refined circular stroke where I'm producing good power with the cranks vertical, while not mashing in the lower part of the downstroke. I pedal seated 90%+ of the time. While it may not be the most efficient or powerful stroke, it works well for technical riding.
    I was assuming seated pedaling and heavy use of ankles/calves. Having just been through a fair amount of research on this topic, I haven't run into any examples that support what you're suggesting but I'd love to hear it if that's possible so, serious question: have you measured your torque throughout the stroke, or how are you reaching the conclusion that it's even throughout?

    A while back I was hoping to measure torque vs. crank angle myself but discovered that (virtually?) all the power meters out there assume roughly constant speed and have a very low sampling rate relative to cadence so I eventually bagged that in favor of finding existing data. But if there's something I missed I'd be interested.

  19. #19
    Join Date
    Feb 2006
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    6,046
    Quote Originally Posted by jono View Post
    I was assuming seated pedaling and heavy use of ankles/calves. Having just been through a fair amount of research on this topic, I haven't run into any examples that support what you're suggesting but I'd love to hear it if that's possible so, serious question: have you measured your torque throughout the stroke, or how are you reaching the conclusion that it's even throughout?

    A while back I was hoping to measure torque vs. crank angle myself but discovered that (virtually?) all the power meters out there assume roughly constant speed and have a very low sampling rate relative to cadence so I eventually bagged that in favor of finding existing data. But if there's something I missed I'd be interested.
    Most studies are done with pro road bikers riding at high output, who are all basicly pedal mashers, they make very little power when the cranks are vertical.

    Circular pedaling is very easy to prove, simply pedal with only one foot.

  20. #20
    Join Date
    Nov 2005
    Posts
    2,833
    Unfortunately, for that purpose, momentum ensures that you can ride with one leg regardless.

    I completely agree that mountain and road differ, but the magnitude is the issue. Assume that Tomac is 3 times as smooth as a roadie and that you're 3 times smoother than that, you'd still vary by about 30% whereas oval rings only correct another ~10-15%. So you'll be better than now with the ability to get more efficient, even if you're in the top 0.1% on smoothness.

    Which muscles are you firing at TDC?

  21. #21
    Join Date
    Jun 2009
    Location
    South of 49
    Posts
    749
    They are all the rage today. All the rage.
    Is it Elliptical or Oval?
    Except I see a lot of mtbr pros racing and winning without them.
    Do they work with an E-13 chain retention system?
    Any good Enduro races or XC races being won by people that stoup to oval levels?
    Will my ankles adjust to working at different points?
    Is there any post-purchase dissonance?
    Will I enjoy the placebo effect?
    Who isn't drinking the koolaid?

  22. #22
    Join Date
    Sep 2005
    Location
    Stowe
    Posts
    4,451
    I just bought a 34 tooth for me yet to be here bike from wolf tooth. The OP has an oval ring I think he just needs to update what his thoughts on it,

  23. #23
    Join Date
    Apr 2012
    Posts
    143
    Been riding an absolute black oval on a 1x11 set up and I love it. I definitely was not a proficient climber with an even pedal stroke but this has seemed to correct what I was doing wrong and works great. Not missing anything on the 3x9 set up I got rid of

  24. #24
    Join Date
    Dec 2008
    Location
    Vacationland
    Posts
    2,891
    Bumping this up. Building up a new frame and buying a whole drivetrain, 1x11. Anyone have more feedback on the ovals?

    I had the biopace back in the day, haven't missed it.

  25. #25
    Join Date
    Dec 2015
    Posts
    388
    I have an Absolute Black, and love it much more than the round ring's I rode for 25 years prior.

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