Best lightweight gearing combination- Mtbr.com
Results 1 to 20 of 20
  1. #1
    mtbr member
    Reputation:
    Join Date
    Apr 2010
    Posts
    18

    Best lightweight gearing combination

    Hey WW's,

    I recently acquired an S-Works road crankset that has 172.5 mm crankarms. A customer at the LBS purchased a Carbon S-works 29'er and swapped cranksets (175mm). I plan on swapping spiders+chainrings and using a Zipp Vuma Quad adapter to make it fit on my aluminum Specialized Hardtail frame.

    My question is, what would be the lightest, best XC racing gearing+shifter combination with the stock 24/38 chainrings? I was thinking Dura Ace 7800 12-25 cassette with my current XTR rear derailleur and xtr shifter, but worry that the 38/12 will be too short of gearing. I never use the small chainring in the local trails/racing, so I am not as worried about the 24/25, which would still be less than a 1:1 ratio.

    Any input/other recommendations appreciated! Worst case scenario I can get 42/28 chainrings and use an xtr 11-32 cassette.

  2. #2
    "They Call Me Bone'z"
    Reputation: facelessfools's Avatar
    Join Date
    Aug 2008
    Posts
    1,609
    i did a coupple races at the end of this season on a 34t rotor ring and a 11-34t ti cassette. 34 11 was high enough for the roads and 1 to 1 was low enough for me.

    ill be going 35t ring and 11-36t xx cassette for 2012. if i dont like it i may go with a road cassette like 27-11 and 25/36 chainrings.
    RAH!

  3. #3
    mtbr member
    Reputation:
    Join Date
    Apr 2010
    Posts
    18
    The only road cassettes that are wide ratio 9 speed road cassettes that I know of are 12-27, unless anybody can correct me on that. In all honesty, with my current triple I have never found myself in the big ring and the 11t cog, so I think I should be able to get away with running a 38/24 crankset and an 11-25 D/A cassette.

    On a side note, is the 7800 D/A rear derailleur compatible with an XTR shifter? or should I stick with my current XTR?

  4. #4
    mtbr member
    Reputation:
    Join Date
    Aug 2007
    Posts
    105
    You could use 11-28 slx 9 speed cassette (230 gram) light and cheap

  5. #5
    "They Call Me Bone'z"
    Reputation: facelessfools's Avatar
    Join Date
    Aug 2008
    Posts
    1,609
    i had 38/27t rings previously and raced that for a majority of the season too. 38 11 is plenty tall for the west coast cup.
    RAH!

  6. #6
    mtbr member
    Reputation: bikerboyj17's Avatar
    Join Date
    Dec 2007
    Posts
    454
    OP: Wait, an S-works road crankset will work on a mountain bike? I thought the spindle was too short.

    Can you please share how you set up this crankset? I have a specialized aluminum hardtail too. What model do you have?

    Thanks!

  7. #7
    mtbr member
    Reputation:
    Join Date
    Oct 2006
    Posts
    94
    What category do you race and what kind of terrain?

  8. #8
    mtbr member
    Reputation:
    Join Date
    Apr 2010
    Posts
    18
    Quote Originally Posted by Kwik View Post
    You could use 11-28 slx 9 speed cassette (230 gram) light and cheap
    Thats about 80 grams heavier than a D/A...

    Quote Originally Posted by facelessfools View Post
    i had 38/27t rings previously and raced that for a majority of the season too. 38 11 is plenty tall for the west coast cup.
    Thanks for the input!

    Quote Originally Posted by bikerboyj17 View Post
    OP: Wait, an S-works road crankset will work on a mountain bike? I thought the spindle was too short.

    Can you please share how you set up this crankset? I have a specialized aluminum hardtail too. What model do you have?

    Thanks!
    I got my frame special, its a 2011 Aluminum M5 Hardtail. We plan on swapping spiders, it should work with the Vuma Quad BB.

    Quote Originally Posted by jthurd View Post
    What category do you race and what kind of terrain?
    Juniors/Cat 2, varying terrain each race.

  9. #9
    mtbr member
    Reputation:
    Join Date
    Apr 2010
    Posts
    18
    Update, checked the spindle length, the road crankset spindle is too short :[

    Anybody know of a lightweight, 172.5mm mountain crankset besides XTR?

  10. #10
    mtbr member
    Reputation:
    Join Date
    Apr 2009
    Posts
    995
    Lightning Cranks, although IMO XTR would be your best option.

  11. #11
    mtbr member
    Reputation:
    Join Date
    Apr 2004
    Posts
    876
    Rotor make their Agilis and 3D crankset in 172.5 as well.

  12. #12
    "They Call Me Bone'z"
    Reputation: facelessfools's Avatar
    Join Date
    Aug 2008
    Posts
    1,609
    Extralite!!
    RAH!

  13. #13
    mtbr member
    Reputation:
    Join Date
    Oct 2006
    Posts
    94
    Profile elite pro. light, stiff, and 172.5

    Add 175g for octalink DA (68mm) BB.

    I have 2 pair, best budget WW crankset... if you can find them.

    Arms are carbon wrapped Al... ie you wont break them.

    Spiders are replaceable. Uses the same spider as the MTB specific Profile alpine pro (heavy) and old school XTR cranksets.
    Shown with w/ TA 30/42 rings.


    Currently putting together a 172.5 SiSL/Zipp Vuma 25/38t setup on a 29er Lenz. Doing a little Jerry-rigging to get it to work on non BB30. This would be a uber light option if your Spec is BB30, albeit expensive.
    Attached Thumbnails Attached Thumbnails Best lightweight gearing combination-profileelite.jpg  


  14. #14
    mtbr member
    Reputation: bikerboyj17's Avatar
    Join Date
    Dec 2007
    Posts
    454
    jthurd- Is this the same crankset?

    http://www.trivillage.com/procra0700...ode=PROCRA0702

  15. #15
    "They Call Me Bone'z"
    Reputation: facelessfools's Avatar
    Join Date
    Aug 2008
    Posts
    1,609
    it uses an octalink BB.... id say make sure you go with an external bearing system. better stiffness lighter and maintenance.
    RAH!

  16. #16
    mtbr member
    Reputation:
    Join Date
    Oct 2006
    Posts
    94
    yup, thats them.

    with the 94bcd spider/rings and octalink BB your good to go.

    If you have a 68mm shell BB you can use a 108mm DA 7700 needle bearing BB which are pretty light. If your frame is 73mm then you have to get creative with the DA BB because the drive side sleeve will screw too far into the BB to attach the lockring. I used some blue locktight to hold it in place without the lockring- worked fine. If you not into every gram just buy an XTR 113mm or 117mm octalink BB for a 73mm shell. I think they are around 200 grams? Its sealed better also, but not rebuildable like the DA.

  17. #17
    mtbr member
    Reputation:
    Join Date
    Oct 2006
    Posts
    94
    If D/A octalink was stiff enough for Lance in his first couple tours I think its good enough for us.

    Other than lightning, extralite, or SiSL show me a lighter 172.5 MTB crankset. You can by those for $5-600, or get this for cheap. Octalink BB's can be had all over the bay for less than 35 bucks, octalink XTR will last just as long as some outboard BBs. standard splined BB tool + crank puller- pretty easy to work with. Sure there are better, lighter cranksets. Depends on what you want to spend.


    Quote Originally Posted by facelessfools View Post
    it uses an octalink BB.... id say make sure you go with an external bearing system. better stiffness lighter and maintenance.

  18. #18
    mtbr member
    Reputation:
    Join Date
    Apr 2010
    Posts
    18
    Yhu all mad. I work for a bike shop so I can get Specialized stuff at attractive employee deals, but unfortunately they do not have a 172.5mm MTB crank option. Perhaps I'll just use the 175's and learn to live with them?

  19. #19
    mtbr member
    Reputation: bikerboyj17's Avatar
    Join Date
    Dec 2007
    Posts
    454
    Get the 175's at a cheap price and be done with it. Post the results of your installation. I'm curious as I have a similar frame.

  20. #20
    mtbr member
    Reputation:
    Join Date
    Aug 2007
    Posts
    105
    [QUOTE=fryer;8276565]Thats about 80 grams heavier than a D/A...

    My dura ace 12- 27 weighed 180 grams, thats just 50 grams lighter. With the slx 11-28 you also have good gear spread at the rear.

    The money you save on the slx cassette, you could spend on lighter not wearing parts, My advice, but I'm not a real weightweeny any more.

Similar Threads

  1. Best Combination?
    By GBR1 in forum Wheels and Tires
    Replies: 3
    Last Post: 10-17-2008, 06:40 PM
  2. A bad combination...
    By Walt Dizzy in forum Wheels and Tires
    Replies: 4
    Last Post: 02-29-2008, 09:37 PM
  3. Is this a right combination?
    By znarf420 in forum Turner
    Replies: 9
    Last Post: 12-19-2006, 09:07 AM
  4. Lightweight rider... lightweight wheels?
    By hiccup in forum Wheels and Tires
    Replies: 19
    Last Post: 05-06-2006, 09:23 PM
  5. Replies: 1
    Last Post: 01-15-2006, 10:52 AM

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.