Advertise on Bikeforums.net



User Tag List

Results 1 to 19 of 19
  1. #1
    Senior Member
    Join Date
    Aug 2005
    Location
    Washington DC area
    Posts
    241
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Converting without horizontal drops

    I have a trusted old hybrid not shifting well. Rather than spending a few bucks on new grip shifters that repeatedly break I'm thinking of converting this one to a single speed. I have a new 17 tooth freewheel and chains, but I've got vertical drops. Don't really want to by a chain tensioner so the question is:

    Can you accomodate the lack of travel with vertical drops simply by adjusting the chain length and/or using a half link?

    Not real concerned about looks, this one is kind of a beater that stays on the porch and follows my kids to school each day.

    Thanks for any advice.

  2. #2
    Senior Member acoustophile's Avatar
    Join Date
    Jun 2008
    Location
    Calgary
    Posts
    66
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    You should be able to get a decent chain tension by adjusting the chain length. If it's still not enough i think adding or subtracting chain link moves the axle 1/2" either way. You could also go with a smaller tooth freewheel or bigger chain ring.

    It's all trial and error with vertical drops.

  3. #3
    Senior Member
    Join Date
    Dec 2007
    Location
    Athens, Ohio
    My Bikes
    Fuji Track, Half built 70s Azuki
    Posts
    1,568
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    since you mentioned the word beater, i assume you aren't interested in investing the money for an ENO hub, but that would be the most effective way for vertical drops.

  4. #4
    Newbie
    Join Date
    Jun 2009
    Posts
    4
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    You would probably be better off with a Singleator-type tensioner. But below is a calculator for the "magic gear" based on your chainstay length, and obviously a half-link gives you more usuable ratios to choose from.

    http://www.eehouse.org/fixin/formfmu.php

  5. #5
    :)
    Join Date
    Nov 2006
    Location
    duluth
    My Bikes
    '07 Pista, '09 Fantom Cross Uno, '8? Miyata, '67 Stingray, '0? Zoo mod trials, Tallbike, Chopper, '73 Schwinn Collegiate, '67 Triumph Chopper, '69 CB350, '58 BSA Spitfire, '73 CB450
    Posts
    3,391
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    If it is a "beater" a little creative filing could give you a little extra wiggle room for tensioning.
    Quote Originally Posted by Santaria View Post
    because physics has more street cred than tarckstars.

  6. #6
    Fresh Garbage hairnet's Avatar
    Join Date
    Apr 2009
    Location
    Los Angeles
    Posts
    10,456
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    If it's not about looks, then why not a tensioner?
    Quote Originally Posted by Scrodzilla View Post
    I'd rather ride a greasy bowling ball than one of those things.
    Bikerowave
    My Bikes

  7. #7
    Delusional Laserbrain Germanicus's Avatar
    Join Date
    Jul 2009
    Location
    South Orange, NJ
    My Bikes
    2008 Specialized Tricross, 1993 Giant Iguana rebuild w/ singlespeed drive train
    Posts
    396
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    You basically have 4 choices.

    1) You can buy a Horizontal Dropout and have a local metal shop cut and weld it into your frame. Prob cost you $30 (surly) plus labor.
    2) You can buy an eccentric hub. (White industies makes them $130 plus labor and $$ of building a wheel)
    3) Chain tensioner ($varies) Surly Singulator about $50. This is probably hte simplest install.
    4) adjusting chain length (using half links to get closest) This is cheapest option but you'll have to get lucky to get an exact fit.
    good luck.

  8. #8
    Breakfast in America pancake4life's Avatar
    Join Date
    Aug 2009
    Location
    California
    Posts
    379
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Germanicus View Post
    3) Chain tensioner ($varies) Surly Singulator about $50. This is probably hte simplest install.
    4) adjusting chain length (using half links to get closest) This is cheapest option but you'll have to get lucky to get an exact fit.
    good luck.
    go with one of these

  9. #9
    Fresh Garbage hairnet's Avatar
    Join Date
    Apr 2009
    Location
    Los Angeles
    Posts
    10,456
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    I see you're in Santa Monica. If you need help in person then you should give the Bikerowave a visit.

    http://www.bikerowave.org/
    Quote Originally Posted by Scrodzilla View Post
    I'd rather ride a greasy bowling ball than one of those things.
    Bikerowave
    My Bikes

  10. #10
    coasterbrakelockup lz4005's Avatar
    Join Date
    Nov 2004
    Location
    parts unknown
    My Bikes
    surly steamroller w/coaster brake, electra single speed cruiser, specialized rockhopper commuter, no-name single speed folder, 700c ultimate wheel, 24" unicycle, specialized bmx lsd, single seat single speed huffy tandem, pink upsidedown parade bike
    Posts
    825
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by uprightbent View Post
    Can you accomodate the lack of travel with vertical drops simply by adjusting the chain length and/or using a half link?
    You'll be able to get your chain within 1/4" of the right length that way.
    If your chainline is straight that should work fine.
    Ride lots, have fun, skid often!

  11. #11
    Senior Member
    Join Date
    Oct 2004
    Location
    Toronto, Ontario
    My Bikes
    Miele Azsora
    Posts
    1,682
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    If you have older style quick release skewers, you can cut down the axle to your dropout width, givign you a little wiggle room. Check it out on Sheldon Brown.
    1988 Miele Azsora

  12. #12
    The bus, Gus mrvile's Avatar
    Join Date
    Oct 2009
    Location
    NYC
    Posts
    976
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    GHOOOOOST RIIIIIING o.O

  13. #13
    Old fart JohnDThompson's Avatar
    Join Date
    Nov 2004
    Location
    Appleton WI
    My Bikes
    Several, mostly not name brands.
    Posts
    11,850
    Mentioned
    3 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by uprightbent View Post
    I have a trusted old hybrid not shifting well. Rather than spending a few bucks on new grip shifters that repeatedly break I'm thinking of converting this one to a single speed. I have a new 17 tooth freewheel and chains, but I've got vertical drops. Don't really want to by a chain tensioner so the question is:

    Can you accomodate the lack of travel with vertical drops simply by adjusting the chain length and/or using a half link?

    Not real concerned about looks, this one is kind of a beater that stays on the porch and follows my kids to school each day.

    Thanks for any advice.
    You already have a derailleur, so why do you need a tensioner? Just adjust the derailleur to hold the chain where you want it. A chain tensioner is nothing more than a derailleur that doesn't shift gears.

  14. #14
    Gimme back my gears!
    Join Date
    Sep 2009
    Location
    San Jose
    My Bikes
    Cannondale Caad9-5 2009, Scattante XLR TT 2009, Trek Y-Foil 77 1998
    Posts
    1,318
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I was thinking of buying This :http://www.amazon.com/Dimension-Chai...7138480&sr=8-2 but I think I might get lucky with a half-link so I'm waiting.

    This is essentially what I was doing with my singulator. The singulator and all those simpler type tensioners will either allow too much chain slippage when power is really applied or downright snap at the spring.

    I actually reversed mine to push the chain up and then have it held by bands, but they have to be replaced every few weeks as they stretch out. Very ghetto for the whole singulator + cog costs about 70 dollars.

    Yes, I have rear derailleurs (Tiagra/105/Ultegra), but I've shamed the bike gods enough with converting a Caad9 so I'll let that go....

    Anyways... I found that tensioner, (which seems extremely sturdy) via here: http://spicercycles.com/online-catal...oners-t806.htm Which has some interesting options I never knew about... just so happens Amazon sells it cheaper.

    I also was thinking of the eccentric hub, but I like having the option of swapping out wheels on a whim.

  15. #15
    Certified Roller
    Join Date
    Sep 2009
    My Bikes
    2009 Cannondale Chase 1, 1976 Motobecane Super Mirage SS
    Posts
    13
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    half link baby.
    1999 Haro Cozmo
    1976 Motobecane Super Mirage SS
    2009 Cannondale Chase 1

    Roll Athens Georgia

  16. #16
    Gimme back my gears!
    Join Date
    Sep 2009
    Location
    San Jose
    My Bikes
    Cannondale Caad9-5 2009, Scattante XLR TT 2009, Trek Y-Foil 77 1998
    Posts
    1,318
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I successfully converted my Caad9 to a single speed. I now run a 50/14 with the inclusion of a half-link, but it fits PERFECTLY!

  17. #17
    I am Noobert.
    Join Date
    Aug 2009
    Posts
    427
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    that must be really fast in the given scenario

  18. #18
    Veteran Racer TejanoTrackie's Avatar
    Join Date
    Jul 2009
    Location
    Ciudad de Vacas, Tejas
    My Bikes
    28 frames + 73 wheels
    Posts
    7,198
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by JohnDThompson View Post
    You already have a derailleur, so why do you need a tensioner? Just adjust the derailleur to hold the chain where you want it. A chain tensioner is nothing more than a derailleur that doesn't shift gears.
    Well, a derailleur cage has 2 pulleys and an SS tensioner only has one. It will still work, but will require more chain and will create a little bit more drag. But, I agree that this is the cheapest way to go if you don't care about looks, and it doesn't require any cutting and grinding.

  19. #19
    Gimme back my gears!
    Join Date
    Sep 2009
    Location
    San Jose
    My Bikes
    Cannondale Caad9-5 2009, Scattante XLR TT 2009, Trek Y-Foil 77 1998
    Posts
    1,318
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Seems a single speed on a Caad9 is a cardinal sin, but for my ride its fine... no real hills and its freewheel, but yeah, avg cadence is 90-100 and i go about 25-26, but when the energy is in and I don't have wind pushing against my body... a solid 30-31 for a few miles, but then my heart rate jumps to 180+

    I did the conversion because I found out for 3 months I not once changed my gears. I figured if my drive-train was to go unused then I might as well protect them from the elements completely and retain their resale value.

Posting Permissions

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