Page 4 of 5 FirstFirst 1 2 3 4 5 LastLast
Results 76 to 100 of 106
  1. #76
    Join Date
    Oct 2003
    Location
    slc
    Posts
    7,249
    Quote Originally Posted by jono View Post
    I would be suprised if the same degree of ovalization is optimum for both low rpm and high, so mountain vs. road seems like it would prefer different shapes FWIW.
    More ovalization being better for lower RPMs?

  2. #77
    Join Date
    Nov 2005
    Posts
    1,626
    Quote Originally Posted by Dantheman View Post
    More ovalization being better for lower RPMs?
    That would be my guess, just because at low rpm an "unbalanced" feeling matters less so you could go past whatever is optimum for spinning fast. Maximizing rpm range might mean something in between?

  3. #78
    Join Date
    Oct 2003
    Location
    slc
    Posts
    7,249
    Went AB. CRC had them cheap and they look to have meatier squarer tooth profiles than the OneUp rings. I really like it. I'll agree with others that it's not a huge difference, but the smoother power delivery and easier turnover past TDC is definitely noticeable while grinding uphill. While spinning fast riding flat road between the house and the trailhead I could feel the oval, almost like a very tiny amount of pedal bob, but only if the pavement was really smooth and I really paid attention. Felt great in all other circumstances. Altachic likes hers a lot too.

  4. #79
    Join Date
    Mar 2007
    Location
    Eugenio Oregón
    Posts
    6,559
    Quote Originally Posted by YourMomJustCalled View Post
    If you're still looking for one, I have an Absolute Black 30T Cinch that you can have. It wasn't for me.

    What didn't you like about it? If no local Utards wanna take that off your hands, I might be willing to buy it off you, if you can drop into an envelope and ship to California.
    _______________________________________________
    "Strapping myself to a sitski built with 30lb of metal and fibreglass then trying to water ski in it sounds like a stupid idea to me.

    I'll be there."
    ... Andy Campbell

  5. #80
    Join Date
    Feb 2006
    Posts
    6,062
    I just bought a 32t round narrow wide to replace the oval that's currently on my yeti SB66, when I put on a new crankset. I don't think the oval works particularly well with the chain growth/rearwardish path of the yeti's suspension, it seems to produce too much pedal feedback (hangs up) riding technical terrain at lower speeds and cadences, and doesn't seem to do much to help with suspension bob or technical climbing. But I'm going to try them both back to back if possible and will also try the oval on a hardtail.

  6. #81
    Join Date
    Mar 2007
    Location
    Eugenio Oregón
    Posts
    6,559
    ^ Interesting - this seems opposite of what I would expect.

    It seems to me that, overall, oval rings would actually improve (reduce) kickback in descending pedal position (pedals level) by increasing the apparent chainring size, thereby decreasing the angle of attack and chain torque on the rear, thereby reducing antisquat and kickback. On the flipside, it would stand to increase antisquat in TDC pedal position, which will depend on the linkage to see if that's good or bad. I can see how this would feel like increased hangup when in TDC, but the increased gear leverage would offset this, no?

    Look at the linkage design antisquat curve on the SB-66:
    http://linkagedesign.blogspot.com/20...b-66-2012.html (use Google Translate)

    Really though, you are talking about 3t of apparent chainring size difference - which should impact antisquat by like less than 5%? - on a linkage that has a pretty neutral antisquat property at 32T avg chainring size.

    Also, I think your climbing style matters here. I'm personally a cadence climber - I really like a bit more antisquat and I'm light enough that for me, hangups don't translate into getting stuck, so much as they translate into leverage I can use to maintain sag position (not get too bogged down into the rear tire) on steeper tech climbs. I actually really miss the climbing properties of my SB-66 compared to my current VPP2 Bronson.
    _______________________________________________
    "Strapping myself to a sitski built with 30lb of metal and fibreglass then trying to water ski in it sounds like a stupid idea to me.

    I'll be there."
    ... Andy Campbell

  7. #82
    Join Date
    Apr 2009
    Location
    Granite, UT
    Posts
    617
    Quote Originally Posted by SchralphMacchio View Post
    What didn't you like about it? If no local Utards wanna take that off your hands, I might be willing to buy it off you, if you can drop into an envelope and ship to California.
    I ride a single speed a bunch and tend to stand and pedal when the going gets tough, even on the geared bike. These rings are effective if you're sitting, not so much if you're standing.

    I'll let it sit here for a few more weeks as winter in the Wasatch wraps up. If someone doesn't want it, I'll let you know.

  8. #83
    Join Date
    Nov 2005
    Posts
    1,626
    Quote Originally Posted by SchralphMacchio View Post
    Also, I think your climbing style matters here. I'm personally a cadence climber - I really like a bit more antisquat and I'm light enough that for me, hangups don't translate into getting stuck, so much as they translate into leverage I can use to maintain sag position (not get too bogged down into the rear tire) on steeper tech climbs. I actually really miss the climbing properties of my SB-66 compared to my current VPP2 Bronson.
    I think this is the biggest difference between how people perceive certain bikes like the Yetis: the new SB's are closer to 100% anti-squat, but the more noticeable characteristic is the tendency to stiffen up on square bumps when climbing, more as a result of the wheel path. Personally, I like it, as the bike gets really efficient and just crawls over, but I can see where the same thing could be seen as locking the rear end or making it less active. (I say that having been probably almost 200 with kit when I was first admiring that "feature." Mostly a style and expectation issue IOW.)

  9. #84
    Join Date
    Feb 2006
    Posts
    6,062
    Quote Originally Posted by SchralphMacchio View Post
    ^ Interesting - this seems opposite of what I would expect.

    It seems to me that, overall, oval rings would actually improve (reduce) kickback in descending pedal position (pedals level) by increasing the apparent chainring size, thereby decreasing the angle of attack and chain torque on the rear, thereby reducing antisquat and kickback. On the flipside, it would stand to increase antisquat in TDC pedal position, which will depend on the linkage to see if that's good or bad. I can see how this would feel like increased hangup when in TDC, but the increased gear leverage would offset this, no?

    Look at the linkage design antisquat curve on the SB-66:
    http://linkagedesign.blogspot.com/20...b-66-2012.html (use Google Translate)

    Really though, you are talking about 3t of apparent chainring size difference - which should impact antisquat by like less than 5%? - on a linkage that has a pretty neutral antisquat property at 32T avg chainring size.

    Also, I think your climbing style matters here. I'm personally a cadence climber - I really like a bit more antisquat and I'm light enough that for me, hangups don't translate into getting stuck, so much as they translate into leverage I can use to maintain sag position (not get too bogged down into the rear tire) on steeper tech climbs. I actually really miss the climbing properties of my SB-66 compared to my current VPP2 Bronson.
    5% can be noticeable on a bike, and I've got a pretty smooth cadence. Before the yeti, I rode FSR bikes for about 15 years, and think that they technical climb much better. I'm still on the fence about the yeti, might eventually switch to a specialized stumpjumper evo or enduro if I can find a good frame for under $1000.

  10. #85
    Join Date
    Jan 2008
    Location
    Whistler
    Posts
    997
    I use one, hidden on inner ring of my road bike. I love it for climbing.
    I'm to vain to use one on my MTB where it's visible to the naked eye.

  11. #86
    Join Date
    Apr 2006
    Location
    SF & the Ho
    Posts
    3,089
    Quote Originally Posted by Dee Hubbs View Post
    I use one, hidden on inner ring of my road bike. I love it for climbing.
    I'm to vain to use one on my MTB where it's visible to the naked eye.
    What size ring do you use on the roadie? What would you compare to a standard ring ?

  12. #87
    Join Date
    Jan 2008
    Location
    Whistler
    Posts
    997
    Quote Originally Posted by mcski View Post
    What size ring do you use on the roadie? What would you compare to a standard ring ?
    I have a Dura Ace 50-34 matched up to a 11-28 cassette. I live in Colorado and all my rides include climbs and I spend a lot of time in the small ring.
    I replaced the 34 with an Absolute Black 34 and I love the smooth cadence and power delivery I get with oval.
    On my Di2 bike its really easy to switch between big ring and small ring gears that have the same ratio.
    Climbing in 50-19 is ratio 5.2, from here I can easily shift to 34-13 with the same ratio of 5.2. I can usually climb longer on a pitch in the Oval ring in the 34-13 combination then in the big round ring with the same ratio.
    Its hard to describe but I can keep my cadence higher and still push the same power. I sound like the marketing lingo, but it feels like a 32T in the climbing aspect and putting the power of a 36down.
    I just ordered the parts to upgrade my Di2 system for Synchro Shift, I am going to program 2 models (one identifying the small ring as 34 (actual) and one as a 36. When the bike shifts based on the next ratio request, this will truly show me if the oval is felt or supporting what I feel.
    Hope this answered you question.

  13. #88
    Join Date
    Apr 2006
    Location
    SF & the Ho
    Posts
    3,089
    Awesome detail. Thx!

  14. #89
    Join Date
    Feb 2006
    Posts
    6,062
    I'm back to a round front ring, 32t race face with a sunrace 10spd 11-40t. I just like the feel of it and have a pretty smooth round pedal stroke. It also seems to reduce bobbing on my yeti SB66 vs. the oval. I haven't ridden the oval in several months, and have also changed wheels, tires, crank and shoes, so this is certainly not a scientific back to back comparison.

  15. #90
    Join Date
    Mar 2007
    Location
    Eugenio Oregón
    Posts
    6,559
    ^ new crank, same geometry or new crank and different length, q-factor, or other???

    Very interesting result. I really wonder if it's the anti-squat that is impacting your bobbing. But changing the crank geo would certainly invalidate the conclusion.
    _______________________________________________
    "Strapping myself to a sitski built with 30lb of metal and fibreglass then trying to water ski in it sounds like a stupid idea to me.

    I'll be there."
    ... Andy Campbell

  16. #91
    Join Date
    Feb 2006
    Posts
    6,062
    Quote Originally Posted by SchralphMacchio View Post
    ^ new crank, same geometry or new crank and different length, q-factor, or other???

    Very interesting result. I really wonder if it's the anti-squat that is impacting your bobbing. But changing the crank geo would certainly invalidate the conclusion.
    Noticeably narrower crank at the same length, stiffer and lighter shoes, clipless. Also running a slightly wider rim with a slightly larger, softer compound rear tire, with a lower pressure - softer overall. Have also changed my rear suspension setup, have removed all volume rings (made it less progressive), increased pressure, reduced sag, increased rebound damping. So that certainly reduces the bobbing. But I do think the round ring helps reduce the bob for me, just a bit, and it feels more natural.

    I will be adding some spacers to improve the chainline, so I might just pull the crank anyway to try the oval ring on the new setup, while I fabricate the spacers - custom shape to match the new xtr M980 crank's tabs.

    Before the Yeti, I rode FSR DH/Freeride frames for about 15 years, which are far more active under pedaling and are much better in technical climbing, much less anti squat. It's actually much harder to clear certain technical climbs around here on the yeti.

  17. #92
    Join Date
    Nov 2005
    Posts
    1,626
    Anti-squat doesn't make a suspension less active (but changing chain length with travel can, and that happens on the Yeti and the FSR in opposite directions). It seems difficult to separate a user's expectations from reality when it comes to movement, though--if you were used to a hard tail I expect you'd find the Yeti to be the easier bike to use in those situations. Having the bike act differently than you expect has more to do with it than fine tuning.

  18. #93
    Join Date
    Mar 2007
    Location
    Eugenio Oregón
    Posts
    6,559
    ^ yeah I agree there about expectations.

    I had a somewhat poor implementation of a horst (Norco Fluid gen 1) that sucked when climbing (squatted like a bad snowboarder trying to ski - oh wait, that's me). Going to the SB-66 seemed like the best climbing machine ever ... loved it more than current VPP2 in seated climbing ability.

    Regardless, I still wonder if the conclusions are valid (for whatever reason) about oval rings affecting bob, for better for worse. Can't wait t try one out this summer.
    _______________________________________________
    "Strapping myself to a sitski built with 30lb of metal and fibreglass then trying to water ski in it sounds like a stupid idea to me.

    I'll be there."
    ... Andy Campbell

  19. #94
    Join Date
    Nov 2005
    Posts
    1,626
    I'm not ready to write off the idea that an oval can make an SB-66 bounce a little, either. My wife runs a small AB on her SB-95 and my impression is that between moving the chain down (it was already below the instant center and therefore contributing to AS>1) and wiggling it up and down there may well be more bob than her 32T round gave. OTOH it's still so minimal that it could also be cadence related if my eyes aren't deceived. All that said, I don't think there's a general conclusion for other bikes there, given the uncommonly high instant center on the old switch design.

  20. #95
    Join Date
    Dec 2008
    Location
    Vacationland
    Posts
    2,002
    I stopped noticing the oval bounce after a dozen or so rides

  21. #96
    Join Date
    Feb 2006
    Posts
    6,062
    So I ended up putting my 32t oval back on, my chainline with the 32t round was way off. The oval has spacers built in. Will get to ride it today hopefully.

    Also needed to shave down a BB spacer to 1.5mm, to correct for my BB width on the frame being too narrow. When I installed a new M980 crank, I found that the arm was way too close to the chainstay on the drive side due to the layout of the frame and the low q-factor crank. I measured the BB at 71.5mm instead of 73mm, it appears to be short on the drive side. It seems that Yeti uses a removable chainguide related insert on the BB. I put in an extra 2.5mm spacer and crossed my fingers, it seemed to work but the chainline was even more out. Now I have shaved down one of the 2.5mm spacers to 1.5mm (1.53 to 1.57 mm measured actual, which is flatness within +/- .001").

    The BB spacer moves the chainline in about 1mm. The oval ring moves it in a bit over 3mm. So I went from a chainline around 50mm, down to 46mm. The chain no longer drops off the largest cog when backpedaling.

    I need to order some extra long chainring bolts and fab up some 1/8" AL spacers in order to mount the 32t round in the proper position.
    Last edited by Damian Sanders; 04-19-2017 at 09:27 AM.

  22. #97
    Join Date
    Feb 2006
    Posts
    6,062
    Bump. Made up some spacers and custom modified long bolts to mount my 32t round ring on xtr M980 2x "Trail" cranks. Seems to have resolved the large cog chainline issue to my satisfaction. I definitely prefer the round ring. The 32T oval just feels choppy and harder to turn over. Keep in mind I'm using non-platform clipless and XC race shoes.
    Last edited by Damian Sanders; 05-17-2017 at 12:00 PM.

  23. #98
    Join Date
    Dec 2015
    Posts
    195
    for me the oval "chop" is only if my cadence is too high. The oval likes a slower cadence IMO. I love the oval since I don't "stall" at 6/12 o'clock in slow tech situations. For me it's definitely better than a round ring.

  24. #99
    Join Date
    Apr 2008
    Location
    Raleigh
    Posts
    3,704
    I just put on an oval. I was sold a mile in. It shines on high output stuff. Steep technical climbs. Really smooths out energy output. I can see how the high cadence high mileage guys might not appreciate it. Need to be struggling up the kind of thing where it's hard to even steer your bike you're going so slow and jerking your body around.
    If you want me to take a dump in a box and mark it tubeless, I will. I got spare time.

  25. #100
    Join Date
    Nov 2005
    Location
    Land of Brine Shrimp and Magic Underwear
    Posts
    5,634
    ^^^
    Agree with this, I've got about 300 miles so far. I'm a bigger gear kind of guy, not a spinner, to begin with. Very noticeable improvement on steep and/or technical climbing. I'm now on a heavier, longer, slacker bike with more suspension and much less anti-squat, ie. more active. In spite of all that, I'm cleaning more technical climbing moves, and getting further up steep, loose stuff with this setup.

    I've got a 34t Rotor Q-Ring with XO1 Eagle 12 speed, 10-50. Rarely use the 50, it's only for 'emergencies'. I think it definitely rewards pushing bigger gears more and spinning high cadence less.

    Oval is sweet!
    There's nothing better than sliding down snow... flying through the air.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •