Rotor 23t granny - quick review- Mtbr.com
Results 1 to 23 of 23
  1. #1
    mtbr member
    Reputation: Broccoli's Avatar
    Join Date
    Jun 2008
    Posts
    5,762

    Rotor 23t granny - quick review

    I was very curious to check what the hype is about those elliptical Rotor rings, so I have spent $65 on a 23t granny ring for an XTR crank. I was going to get 24t one anyway, to get a more useful range with 12-27 cassette. This one is supposed to be an equivalent to 24t when pushing down, and 22t in dead spots.

    It was a perfect fit for the non-standard XTR M970 small chainring. It seemed about the same weight, and it is black, not silver so it looks a bit better. It went on a cheap titanium hardtail, that is about 20.5lb with trail capable tires.

    Got about three hours riding around local park at El Corte de Madera (Skeggs), which has a fair amount of climbing (probably 2500ft total today) with few steep technical spots. Good terrain for a light hardtail - though I mostly see burly trail bikes around.

    On flat surface pedaling in this Q-ring produced some odd sensation that chain slacks up. Did not like it. I do not think I will be getting a Q-ring for the middle ring. I am not an expert cyclist, but a mere mortal, so all those studies with lactate and O2 are nothing to me.

    On steep broken up climbs it felt like I was getting a little extra push on each stroke - and it was noticably easier to pass dead spots and keep pedaling. I cleared few spots that I usually need 22/27 in 23/24 and it was smoother.

    So for this particular application I think I like it. It was noticable, and it did help a bit. I will keep the granny, and maybe get one for my other bikes. I do not think I would care about the middle or big ring though.

    So if you carry around your granny ring and actually do use it , I think swapping 22 to this 23t elliptical is a worthy upgrade.

  2. #2
    mtbr member
    Reputation:
    Join Date
    Apr 2009
    Posts
    995
    I was thinking about getting some a while back but there so expensive.
    Also do you have a good pedal stroke? that could be causing it to act weird(maybe not, just a thought). I just found out that my pedal stroke is terrible.

  3. #3
    mtbr member
    Reputation: Broccoli's Avatar
    Join Date
    Jun 2008
    Posts
    5,762
    Quote Originally Posted by COLINx86
    Also do you have a good pedal stroke? that could be causing it to act weird(maybe not, just a thought). I just found out that my pedal stroke is terrible.
    I think I have decent stroke, improved it since I started riding a fixie, and that is exactly the reason it feels weird with a non-round chainring. I guess one can relearn, but I do not feel that I want to. For rough trails climbing spinning is not smooth anyway, and I personally did like how this chainring behaves.

  4. #4
    mtbr member
    Reputation:
    Join Date
    Jul 2007
    Posts
    183
    Curmy,

    Quite interesting. I run same drivetrain setup as you so this might be a useful upgrade. Granny ring only gets used on climbs so if it is a benefit there I can ignore any problems/odd sensations it might have on flat surfaces.

    Where did you buy the rotor from if you don't mind me asking?

    Thanks for the review.

  5. #5
    mtbr member
    Reputation: Broccoli's Avatar
    Join Date
    Jun 2008
    Posts
    5,762
    Quote Originally Posted by gixer7
    Where did you buy the rotor from if you don't mind me asking?
    Directly from US distributor: http://www.rotorbikeusa.com/

  6. #6
    gone for a bike ride
    Reputation: culturesponge's Avatar
    Join Date
    Aug 2007
    Posts
    1,973
    thanks for the quick review, i'm glad the Q-granny worked out as well as hoped.

  7. #7
    mtbr member
    Reputation:
    Join Date
    Nov 2006
    Posts
    213
    Weren't eliptical rings tried in the mid '80's? I don't think the fad lasted too long if my memory serves me right

  8. #8
    mtbr member
    Reputation: Broccoli's Avatar
    Join Date
    Jun 2008
    Posts
    5,762
    Quote Originally Posted by moto367
    Weren't eliptical rings tried in the mid '80's? I don't think the fad lasted too long if my memory serves me right
    Biopace did the exact opposite thing. I guess I can approximate it by rotating the ring by 90 degrees. They also had shape that was less gradual.

    By all accounts Rotor got it right this time. From my limited experience - and from the common sense analysis of what they try to achieve - I would tend to agree.

    There is a good write up on the difference on Rotor's website.

  9. #9
    mtbr member
    Reputation:
    Join Date
    Feb 2004
    Posts
    86
    How about keeping traction on steep loose sections? Does the extra 'push' break the rear wheel loose more easily or do you feel like you can control it?

    G.

  10. #10
    STS
    STS is offline
    mtbr member
    Reputation: STS's Avatar
    Join Date
    Jun 2004
    Posts
    530
    you control it much better, because the result is like a almost total round stroke
    not the piston-like your legs do with a standard round ring

  11. #11
    mtbr member
    Reputation: MichauxYeti's Avatar
    Join Date
    Nov 2005
    Posts
    682
    I ran a 42t Rotor on my cyclocross bike last year and absolutely loved it. I was climbing hills in that ring at a similar perceived effort to what I felt pushing a 38t round ring, just at a higher speed. I appreciate that the ring can be rotated to a different set of mounting holes based on the type of riding you do and your pedaling style. I've heard position 2 is typical for road racing, however position 3 worked best for cross, and I suspect for mountain biking as well.

  12. #12
    Always Learning
    Reputation: BruceBrown's Avatar
    Join Date
    Jan 2004
    Posts
    9,606
    Quote Originally Posted by Gringo
    How about keeping traction on steep loose sections? Does the extra 'push' break the rear wheel loose more easily or do you feel like you can control it?

    G.
    It's a very smooth stroke and the rear wheel does not break loose. I run the 2 x 9 Q-Rings (27/40) on my JET 9 and climbing on steep and loose couldn't be better (seating or standing). Keep in mind, proper tire pressure and a learned cadence for climbing the steep and loose are also required.

    BB

  13. #13
    mtbr member
    Reputation: Broccoli's Avatar
    Join Date
    Jun 2008
    Posts
    5,762
    Quote Originally Posted by BruceBrown
    It's a very smooth stroke and the rear wheel does not break loose. I run the 2 x 9 Q-Rings (27/40) on my JET 9 and climbing on steep and loose couldn't be better (seating or standing). Keep in mind, proper tire pressure and a learned cadence for climbing the steep and loose are also required.

    BB
    From a mechanical point of view increasing gear ratio when you increase force on a pedal should smooth out effective torque at the rear wheel, if anything, shouldn't it?

    From a bio-mechanical point I found that the noticeable (though obviously not magical) benefit for me was on obstacles, like large roots and ledges where I had to get over them without getting stuck in a pedaling dead spot. I think it may be even more noticeable with platform pedals.

  14. #14
    mtbr member
    Reputation:
    Join Date
    Jun 2006
    Posts
    634
    That's the idea. I'm interested in getting the rotor middle ring to prevent wheel slip when mashing out of the saddle, and stalling out in the dead spot.
    You'll have to give us an update in a few months as to how durable they are. Expensive part to replace every 6 months.

  15. #15

    Reputation:
    Join Date
    Nov 2007
    Posts
    37
    Flat surface in any granny gear could cause some very weird sensations. I am running a rotor middle chainring on my XC race bike and it is Awesome. I can feel a huge difference when I get back on the round rings the rotor middle makes climbing every hill in the middle chainring feesible and on the flats i still remain in the same gear. Worth the upgrade.



    On flat surface pedaling in this Q-ring produced some odd sensation that chain slacks up. Did not like it. I do not think I will be getting a Q-ring for the middle ring. I am not an expert cyclist, but a mere mortal, so all those studies with lactate and O2 are nothing to me.

  16. #16
    mtbr member
    Reputation: Broccoli's Avatar
    Join Date
    Jun 2008
    Posts
    5,762
    Quote Originally Posted by kcreager
    Flat surface in any granny gear could cause some very weird sensations.
    I was comparing it with a regular granny.

    Quote Originally Posted by kcreager
    I am running a rotor middle chainring on my XC race bike and it is Awesome. I can feel a huge difference when I get back on the round rings the rotor middle makes climbing every hill in the middle chainring feesible and on the flats i still remain in the same gear.
    What cassette do you run? I found 32/27 too high for my abilities. I was contemplating switching to 27-40 with 11-32 cassette, but I guess I will stay with the XTR triple. Front shifts are so smooth, it is not a problem to use it.

  17. #17
    mtbr member
    Reputation:
    Join Date
    Jul 2008
    Posts
    168
    Do you think a 32/23 set of rings with a 11-27 cassette would be better? I was thinking it would be a good combo...

  18. #18
    STS
    STS is offline
    mtbr member
    Reputation: STS's Avatar
    Join Date
    Jun 2004
    Posts
    530
    Quote Originally Posted by strader
    That's the idea. I'm interested in getting the rotor middle ring to prevent wheel slip when mashing out of the saddle, and stalling out in the dead spot.
    You'll have to give us an update in a few months as to how durable they are. Expensive part to replace every 6 months.
    it's made with a very durable aluminum (I don't know which)
    by the moment mine are lasting 2 times shimano XTR ones did, and still in very good condition

  19. #19
    No longer 26
    Reputation: G-Live's Avatar
    Join Date
    Jan 2004
    Posts
    3,090
    Quote Originally Posted by Jonnybravo
    Do you think a 32/23 set of rings with a 11-27 cassette would be better? I was thinking it would be a good combo...
    why not 23/34 or 36 to give you a little more range? I am finding a standard 24 granny and 36 middle is all I'd need up front. The 23 Qring has me thinking about trying one.

    G
    You can't depend on honest answers from dependant hands...

  20. #20
    Always Learning
    Reputation: BruceBrown's Avatar
    Join Date
    Jan 2004
    Posts
    9,606
    Quote Originally Posted by Curmy
    From a mechanical point of view increasing gear ratio when you increase force on a pedal should smooth out effective torque at the rear wheel, if anything, shouldn't it?

    From a bio-mechanical point I found that the noticeable (though obviously not magical) benefit for me was on obstacles, like large roots and ledges where I had to get over them without getting stuck in a pedaling dead spot. I think it may be even more noticeable with platform pedals.
    Since I don't have the granny ring with my 2 x 9 (27/40T) rings my application differs from yours. However, climbing the steeps that are longer in duration or if they are short, off-camber, difficult balance steeps - I experience the same sensation as you are with my 27T granny. That being, I don't get stuck in a pedaling dead spot. And the 40T on those connecting pavement or gravel sections between singletrack really makes it nearly impossible to not have a smooth stroke while hammering away. I can easily compare my 2 x 9 on the other bike that has the normal round rings (29/42) riding the same climbs, short steeps and connecting pavement/gravel sections.

    It would be fun to give the Rotor RS4 crankset a go some day to get the full benefit. But for now, I'm enjoying the benefits of the 2 x 9 Q-Rings for my riding.

    BB

  21. #21
    mtbr member
    Reputation:
    Join Date
    Jul 2008
    Posts
    168
    24 granny and 36 middle with a road cassette? Wouldnt be too brutal?

    Quote Originally Posted by G-Live
    why not 23/34 or 36 to give you a little more range? I am finding a standard 24 granny and 36 middle is all I'd need up front. The 23 Qring has me thinking about trying one.

    G

  22. #22

    Reputation:
    Join Date
    Nov 2007
    Posts
    37
    Quote Originally Posted by Curmy
    I was comparing it with a regular granny.



    What cassette do you run? I found 32/27 too high for my abilities. I was contemplating switching to 27-40 with 11-32 cassette, but I guess I will stay with the XTR triple. Front shifts are so smooth, it is not a problem to use it.
    I run it with an 11-34 cassette. However I am sort of a freak when it comes to climbing so running the granny is a good option if you run an 11-32 or somthing even smaller. 40-27 is a sweet combo and if rotor made those sized rings i would totally go for it.

  23. #23
    gone for a bike ride
    Reputation: culturesponge's Avatar
    Join Date
    Aug 2007
    Posts
    1,973
    Quote Originally Posted by kcreager
    I run it with an 11-34 cassette. However I am sort of a freak when it comes to climbing so running the granny is a good option if you run an 11-32 or somthing even smaller. 40-27 is a sweet combo and if rotor made those sized rings i would totally go for it.
    (not spam rensho!) your in luck - that combo (110/74bcd 40/27 MTB XC2 ) is on the Rotor website

Members who have read this thread: 0

Posting Permissions

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

THE SITE

ABOUT MTBR

VISIT US AT

© Copyright 2019 VerticalScope Inc. All rights reserved.