What rear cog for 20tooth ring?- Mtbr.com
Results 1 to 31 of 31
  1. #1
    bike rider
    Reputation: mattkock's Avatar
    Join Date
    Mar 2009
    Posts
    1,152

    What rear cog for 20tooth ring?

    I'm about to start building my first 29er and I have a sweet 20tooth chainring that I'd like to run but what cog should I run in Texas on mostly flat trails? I've got King cogs in 12, 13, 14, 15, and 16tooth. I know some people on here frown upon Micro Drive setups so just save it, Please, for the children. I don't know what that means. I need 29er gearing advice. Thanks.

    I currently ride a 14.4lb Ti 26" SS and I'm going to shoot for 15-16lbs for my Niner. We'll see.
    My Bikes Kick Ass!!!

  2. #2
    mtbr member
    Reputation: ricot83's Avatar
    Join Date
    Jul 2008
    Posts
    655
    thats gonna suck running a 20t ring on flat trails.... on the other hand what gearing do you have on the 26"

  3. #3
    mtbr member
    Reputation:
    Join Date
    Aug 2006
    Posts
    234
    Find one of the many gear inch calculators, there is one on Vassago's site. Figure how many gear inches you are running on your 26 inch bike, figure out what cog you need to come up with about the same ratio.

  4. #4
    mtbr member
    Reputation: supersize's Avatar
    Join Date
    Aug 2005
    Posts
    180
    This should help you out.
    http://www.sheldonbrown.com/gears/

    What crank are you going to use that has a 20T? I was thinking about running a small front ring for clearance. Only thing I could find that small were BMX cranks, but they are way heavy.

  5. #5
    bike rider
    Reputation: mattkock's Avatar
    Join Date
    Mar 2009
    Posts
    1,152
    I run a 24x12 on my 26er and they both have Sweetwing cranks with compact spiders. I've already bolted the 20t up to the cranks and it looks AWESOME! I'm not at home but when i am i'll post pics up of the ti SS. It's in the WW forum under (my new WW bike, yeah). I'll go check out the link, Thank you guys.
    My Bikes Kick Ass!!!

  6. #6
    Sup
    Reputation: Burnt-Orange's Avatar
    Join Date
    Dec 2008
    Posts
    1,696
    12 tooth would be close to the 20/32 combo most bikes come with
    32/20=1.6
    20/12=1.666666666666666666666666666666666666666666666 667

  7. #7
    San Diego County
    Reputation: Duzitall's Avatar
    Join Date
    Feb 2004
    Posts
    1,475
    It's really better to run rings and cogs with more teeth. Teeth and chains last longer. That said I have run a 22-16 or 14 in a pinch can't remember which.
    Quote Originally Posted by turnerbikes View Post
    Of course the easiest way to fix this is to go for a hike.
    DT

  8. #8
    Schipperkes are cool.
    Reputation: banks's Avatar
    Join Date
    Feb 2004
    Posts
    4,154

    groundupdesigns number 174... single speed 29er. She is made of steel, has a pierced downtube for maximal clearance and very short chainstay length, features our own, widely imitated CNC machined sliding disc brake dropouts, hand compound bent seatstays, and custom 22x13 gearing. This is Eric Baar's personal ride.
    Quote Originally Posted by mikesee
    Better suited to non-aggressive 125# gals named Russell.
    I ride so slow, your Garmin will shut off.

  9. #9
    mtbr member
    Reputation: Zion Rasta's Avatar
    Join Date
    Jan 2004
    Posts
    1,420
    No offense dude, but you are either michael jackson's brother or you need to choose a different sport.
    I ride a 34x19 on a 29er and find it too easy for "texas".

    a 20t front chain ring is stupid unless you are using your bike to haul a trailer with 100 cases of beer....

    Seriously, please....
    Sit and spin my ass...

  10. #10
    mtbr member
    Reputation: Zion Rasta's Avatar
    Join Date
    Jan 2004
    Posts
    1,420

    Dude

    Quote Originally Posted by banks

    groundupdesigns number 174... single speed 29er. She is made of steel, has a pierced downtube for maximal clearance and very short chainstay length, features our own, widely imitated CNC machined sliding disc brake dropouts, hand compound bent seatstays, and custom 22x13 gearing. This is Eric Baar's personal ride.
    You need to 5S your shop....
    Sit and spin my ass...

  11. #11
    bike rider
    Reputation: mattkock's Avatar
    Join Date
    Mar 2009
    Posts
    1,152
    No offense taken. I am not Michael Jacksons brother and I Love my sport, so much in fact that I've even been Texas state champ a few times and Louisiana state champ once and Oh yeah, Utah state champ once so I think I'll stick with Mountain Biking but thanks for the non advice Zion Rasta (if that indeed is your real name). Here is a shot of the SS I ride now with a 24x12 gearing. I think that a 21x12 would be perfect but I think at first I'll try the 20x12 I have lying around.

    My Bikes Kick Ass!!!

  12. #12
    bike rider
    Reputation: mattkock's Avatar
    Join Date
    Mar 2009
    Posts
    1,152

    I forgot...............

    Banks, tell Eric that his bike is SWEET and I think his shop looks just fine. Zion Rasta is a Prick. (he's from Dallas)
    My Bikes Kick Ass!!!

  13. #13
    mtbr member
    Reputation: Zion Rasta's Avatar
    Join Date
    Jan 2004
    Posts
    1,420

    Fine dude

    Quote Originally Posted by mattkock
    Banks, tell Eric that his bike is SWEET and I think his shop looks just fine. Zion Rasta is a Prick. (he's from Dallas)
    I am just saying, what is up with the tiny gears, is that a self reflection of something else?

    Seriously, 20t? Congrats on your accomplishments.
    Why don't you start a thread "Show your tiny little ringed single speed"

    So champion, Let me know when you are in Dallas and let's go for a ride. Beer is on me, and come down.....
    Sit and spin my ass...

  14. #14
    mtbr member
    Reputation: Zion Rasta's Avatar
    Join Date
    Jan 2004
    Posts
    1,420
    Your bike looks really heavy, with all those heavy components... Try going for a 12lbs bike and then maybe you'll win the Worlds...
    Sit and spin my ass...

  15. #15
    All fat, all the time.
    Reputation: Shark's Avatar
    Join Date
    Feb 2006
    Posts
    8,183
    wow, enough hating already!
    It's obviously working for him, & hey, it's his bike so who cares how small a chainring he wants!

    Definitely get sweet clearance

  16. #16
    mtbr member
    Reputation: ricot83's Avatar
    Join Date
    Jul 2008
    Posts
    655
    matkock what about 20t x 11t does that match your 26er setup....?

  17. #17
    transmitter~receiver
    Reputation: meltingfeather's Avatar
    Join Date
    May 2007
    Posts
    9,307
    Quote Originally Posted by Shark
    [...]who cares how small a chainring he wants!
    douchebags from dallas.

  18. #18
    bike rider
    Reputation: mattkock's Avatar
    Join Date
    Mar 2009
    Posts
    1,152
    Yeah 20x11 is Perfect but the chainline would be way off. The only reason I'm wanting to run the 20t is because I've had it for years, it came off an 18.2lb Ti hardtail with amp fork I had back in 1999. I guess that being the Weight Weenie that I am I figured smaller ring, smaller cog, less chain = less weight. If my logic is bad please let me know Zion Rasta. I have never or will I ever trash another persons bike or component choices, ever, at least they're riding bikes.

    'With age comes clarity and wisdom and since I'm banging on 40 I have some (not a lot) of both.
    My Bikes Kick Ass!!!

  19. #19
    transmitter~receiver
    Reputation: meltingfeather's Avatar
    Join Date
    May 2007
    Posts
    9,307
    Quote Originally Posted by mattkock
    Yeah 20x11 is Perfect but the chainline would be way off. The only reason I'm wanting to run the 20t is because I've had it for years, it came off an 18.2lb Ti hardtail with amp fork I had back in 1999. I guess that being the Weight Weenie that I am I figured smaller ring, smaller cog, less chain = less weight. If my logic is bad please let me know Zion Rasta. I have never or will I ever trash another persons bike or component choices, ever, at least they're riding bikes.

    'With age comes clarity and wisdom and since I'm banging on 40 I have some (not a lot) of both.
    What does the gear ratio/cog selection have to do with the chainline?

  20. #20
    mtbr member
    Reputation: Zion Rasta's Avatar
    Join Date
    Jan 2004
    Posts
    1,420

    Weight Wenie

    Quote Originally Posted by mattkock
    Yeah 20x11 is Perfect but the chainline would be way off. The only reason I'm wanting to run the 20t is because I've had it for years, it came off an 18.2lb Ti hardtail with amp fork I had back in 1999. I guess that being the Weight Weenie that I am I figured smaller ring, smaller cog, less chain = less weight. If my logic is bad please let me know Zion Rasta. I have never or will I ever trash another persons bike or component choices, ever, at least they're riding bikes.

    'With age comes clarity and wisdom and since I'm banging on 40 I have some (not a lot) of both.
    Ok so let's get serious for a second. I kind of figured you were a WW since a small drive train like that would not last very long. It just was plain simple silly at first, but I guess if you are obsessed with weight that is the way to go.

    22X13 is the same as a 34x20 so I guess if the gear is comfortable to you and no chainline problems then I guess is ok.
    I bet you are eating chaing rings like crazy.

    And no I am not a douche. I was just making a sarcastic, silly, stupid remark but I guess different people react differently to comments.
    Sit and spin my ass...

  21. #21
    San Diego County
    Reputation: Duzitall's Avatar
    Join Date
    Feb 2004
    Posts
    1,475
    Quote Originally Posted by Zion Rasta
    I guess different people react differently to comments.
    I thought maybe you got hold of some paraquat pot

    Just kidding dude

    Hey Banks, the 174 looks great!
    Quote Originally Posted by turnerbikes View Post
    Of course the easiest way to fix this is to go for a hike.
    DT

  22. #22
    transmitter~receiver
    Reputation: meltingfeather's Avatar
    Join Date
    May 2007
    Posts
    9,307
    Quote Originally Posted by Zion Rasta
    Ok so let's get serious for a second. I kind of figured you were a WW since a small drive train like that would not last very long. It just was plain simple silly at first, but I guess if you are obsessed with weight that is the way to go.

    22X13 is the same as a 34x20 so I guess if the gear is comfortable to you and no chainline problems then I guess is ok.
    I bet you are eating chaing rings like crazy.

    And no I am not a douche. I was just making a sarcastic, silly, stupid remark but I guess different people react differently to comments.
    OK, seriousness...
    He's had the chainring since before 1999 if I read right, so... "eating chaing [sic] rings" doesn't seem to be happening.
    You made a few antagonistic, stupid remarks in a row that didn't offer anything other than a glimpse at douchiness... hence the reaction. If you say you aren't a douche, I'll buy it, since it won't cost me anything. D1ck size comments?
    there are a "bunch" of "texas" trails that would make "you" cry on your "easy" 34:19.
    Seriously, please...

  23. #23
    bike rider
    Reputation: mattkock's Avatar
    Join Date
    Mar 2009
    Posts
    1,152
    OK if you've ever put a cassette on you know that an 11tooth cog doesn't slide on at all it just butts up against the end of the cassette body of the hub so I would have to find or make some spacers for the crank spider to set the ring out farther. I'm searching for a 21t ring but like I said I'll try my 20x12 and see how it works. The Carbon Niner Air 9 doesn't even come out till March so I'll keep looking. I'm shooting for 14-15lbs rigid SS with disc brakes, we'll see.
    My Bikes Kick Ass!!!

  24. #24
    mtbr member
    Reputation: Zion Rasta's Avatar
    Join Date
    Jan 2004
    Posts
    1,420

    Chaing haha

    Quote Originally Posted by meltingfeather
    OK, seriousness...
    He's had the chainring since before 1999 if I read right, so... "eating chaing [sic] rings" doesn't seem to be happening.
    You made a few antagonistic, stupid remarks in a row that didn't offer anything other than a glimpse at douchiness... hence the reaction. If you say you aren't a douche, I'll buy it, since it won't cost me anything. D1ck size comments?
    there are a "bunch" of "texas" trails that would make "you" cry on your "easy" 34:19.
    Seriously, please...
    Where? In Houston?

    Ok, enough! I don't care, let's go ride now.
    Sit and spin my ass...

  25. #25
    ballbuster
    Reputation: pimpbot's Avatar
    Join Date
    Dec 2003
    Posts
    12,717

    Something thick, beefy...

    Quote Originally Posted by mattkock
    I'm about to start building my first 29er and I have a sweet 20tooth chainring that I'd like to run but what cog should I run in Texas on mostly flat trails? I've got King cogs in 12, 13, 14, 15, and 16tooth. I know some people on here frown upon Micro Drive setups so just save it, Please, for the children. I don't know what that means. I need 29er gearing advice. Thanks.

    I currently ride a 14.4lb Ti 26" SS and I'm going to shoot for 15-16lbs for my Niner. We'll see.
    ... and made of the hardest, nastiest Grade5 steel you can find, because its gonna wear out crazy fast, as well as your chain and 20t ring up front.

  26. #26
    Nouveau Retrogrouch SuperModerator
    Reputation: shiggy's Avatar
    Join Date
    Dec 1998
    Posts
    48,236
    Quote Originally Posted by mattkock
    Yeah 20x11 is Perfect but the chainline would be way off. The only reason I'm wanting to run the 20t is because I've had it for years, it came off an 18.2lb Ti hardtail with amp fork I had back in 1999. I guess that being the Weight Weenie that I am I figured smaller ring, smaller cog, less chain = less weight. If my logic is bad please let me know Zion Rasta. I have never or will I ever trash another persons bike or component choices, ever, at least they're riding bikes.

    'With age comes clarity and wisdom and since I'm banging on 40 I have some (not a lot) of both.
    fewer teeth = higher friction, increased wear. Go as big as possible front and rear for best efficiency. You can feel the difference. Save the 20T for a gearie.
    mtbtires.com
    The trouble with common sense is it is no longer common

  27. #27
    transmitter~receiver
    Reputation: meltingfeather's Avatar
    Join Date
    May 2007
    Posts
    9,307
    Quote Originally Posted by mattkock
    OK if you've ever put a cassette on you know that an 11tooth cog doesn't slide on at all it just butts up against the end of the cassette body of the hub so I would have to find or make some spacers for the crank spider to set the ring out farther. I'm searching for a 21t ring but like I said I'll try my 20x12 and see how it works. The Carbon Niner Air 9 doesn't even come out till March so I'll keep looking. I'm shooting for 14-15lbs rigid SS with disc brakes, we'll see.
    Hmmm... I have put many a cassette on and now that you mention it, I did know that the 11t cog doesn't slide on. However, I don't have experience building micro-drive bikes, so it's never been an issue or something I've given much thought to. I'm sure there are plenty of things like that.

  28. #28
    mtbr platinum member
    Reputation: bikerx40's Avatar
    Join Date
    Jan 2004
    Posts
    1,426
    Smaller chainrings also means that the chain links need to bend more around the chainring which is less efficient that the same ratio created with larger chainrings & cogs. I'm sure it's a small amount, but so is the total number of watts created by a human on a bike.
    I stopped driving my bike into my garage - I'm now protected with Roof Rack Ranger app for my iPhone.

  29. #29
    transmitter~receiver
    Reputation: meltingfeather's Avatar
    Join Date
    May 2007
    Posts
    9,307
    Quote Originally Posted by Zion Rasta
    Where? In Houston?
    definitely... kr4zy hills down there.
    mmm... off hand i was thinking:
    terlingua
    st. jo
    tapatio
    city park (austin)
    camp eagle
    franklin

    Quote Originally Posted by Zion Rasta
    Ok, enough! I don't care, let's go ride now.
    damn... i'd be riding but it's raining balls here, but i'll take it after nearly two years of drought.

  30. #30
    bike rider
    Reputation: mattkock's Avatar
    Join Date
    Mar 2009
    Posts
    1,152
    I get all of the reasons to not run a micro drive but I'm over 1734 miles on my Ti SS with a 24x12 drivetrain and so far so good. I just thought the 20x12 would look SICK! I'm sure that the 20 won't be up for too much abuse (it only weighs 18g) but I'll try it anyway. Like I said, the frame won't be available till March so I'll just gather parts and dream.
    My Bikes Kick Ass!!!

  31. #31
    mtbr member
    Reputation: boomn's Avatar
    Join Date
    Jul 2007
    Posts
    10,035
    Quote Originally Posted by bikerx40
    Smaller chainrings also means that the chain links need to bend more around the chainring which is less efficient that the same ratio created with larger chainrings & cogs. I'm sure it's a small amount, but so is the total number of watts created by a human on a bike.
    i was able to notice a difference in smoothness between 32x18 and 36x20

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.