Fixy conversion using vertical dropouts

PhilWakelin
PhilWakelin Posts: 2
edited September 2013 in Workshop
Is it possible to do a fixy conversion using a frame with vertical dropouts and a chain tensioner? I'm thinking that this probably requires sliding dropouts as the chain tensioner will collapse if you attempt to back pedal on a fixy?

Comments

  • you can do it with a magic ratio but I wouldn't recommend it.
  • In short you can't build a fixy with a chain tensioner, as you stated the tensioner will collapse with back pedalling.

    You can build a fixy with vertical dropouts, if you can find a 'magic gear' combination of chainring and sprocket which exactly matches the chain length. Using half-links can make this more straightforward. You will be able to find online links which allow you to calculate the magic gear combinations.

    Try this for starters...

    http://www.63xc.com/toddp/halflink.htm

    I don't think it's an exact science, and some trial and error may be involved!
  • e999sam
    e999sam Posts: 426
    You could try with a wheel built with this hub.http://jail.sine.com/sheldonbrown/sheld ... te-eno.jpg
  • redvee
    redvee Posts: 11,922
    If you're using a 130mm frame you could use this.

    http://www.wiggle.co.uk/surly-fixxer-hub-converter/
    I've added a signature to prove it is still possible.
  • If you want to use a 130mm dropout road bike you could weld up a freehub. Won't help with the chain length though.
  • Monty Dog
    Monty Dog Posts: 20,614
    Two options - eccentric hub (White ENO) or eccentric BB (Exentriker / Beer Components)
    I've got both with equal success - Eno hub is probably the easiest / neatest - its a well made piece of kit. My fixie is a Battaglin full-carbon race frame, carbon cranks etc - goes up hills like a scalded cat, but very stiff and unforgiving.

    Chain tensioner + fixed gear = blood + pain
    Make mine an Italian, with Campagnolo on the side..
  • Use the DMR single tension seeker just pushes down on the chain then tighten the bolt and is not affected by back pedaling as it's in a fixed position.
  • Monty Dog
    Monty Dog Posts: 20,614
    baznav73 wrote:
    Use the DMR single tension seeker just pushes down on the chain then tighten the bolt and is not affected by back pedaling as it's in a fixed position.

    OK you try it, we'll watch! The tension in a fixed gear chain will simply collapse the tensioner. Tensioner is OK for freewheel but DON'T USE A TENSIONER WITH A FIXED GEAR!
    Make mine an Italian, with Campagnolo on the side..
  • nicklouse
    nicklouse Posts: 50,675
    baznav73 wrote:
    Use the DMR single tension seeker just pushes down on the chain then tighten the bolt and is not affected by back pedaling as it's in a fixed position.
    please do it and have someone video you on it.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • nicklouse
    nicklouse Posts: 50,675
    Monty Dog wrote:
    Two options - eccentric hub (White ENO) or eccentric BB (Exentriker / Beer Components)
    I've got both with equal success - Eno hub is probably the easiest / neatest - its a well made piece of kit. My fixie is a Battaglin full-carbon race frame, carbon cranks etc - goes up hills like a scalded cat, but very stiff and unforgiving.

    Chain tensioner + fixed gear = blood + pain


    now i was wondering about the ghetto tensioner. a free cog in-between the chain runs.

    otherwise known as Ghost rings.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown