Advertise on Bikeforums.net



User Tag List

Results 1 to 15 of 15
  1. #1
    Senior Member sprockets's Avatar
    Join Date
    Jul 2002
    Location
    Toronto, Ontario
    Posts
    161
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Converting a single speed to 8 speed internal hub

    I've just bought a single speed bike that I want to convert to an internal hub geared bike. At first this seemed like the easiest bet but it just occurred to me that I may have to braze on some parts to the bike. Fortunately it's a steel frame so it's possible if I have to, I just want to know if I have any other options. I've never done this before, does anyone have a link to a site with information on how to braze stuff to a bike frame (or even a generic brazing info site)

    Thx.
    *************************
    As god as my witness, I thought turkeys could fly

  2. #2
    Senior Member sprockets's Avatar
    Join Date
    Jul 2002
    Location
    Toronto, Ontario
    Posts
    161
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Is it possible to just solder the parts necessary for the gear cable to the frame or will it not be strong enough?

    This is a pic of the bike I will be converting:

    *************************
    As god as my witness, I thought turkeys could fly

  3. #3
    dbg
    dbg is offline
    Si Senior dbg's Avatar
    Join Date
    Nov 2004
    Location
    Naperville, Illinois
    My Bikes
    Too Numerous (not)
    Posts
    2,313
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    The cablehousing from the shifter can go all the way to the hub. On one of my builds I used a hose clamp to to attach a cablestop on the chain stay. I then had bare cable between the downtube cablestop and the chainstay stop. On all subsequent internal hub builds I just used plastic cable ties to hold the housing all the way from shifter to hub based cablestop. That works just fine.
    David Green, Naperville, IL USA "The older I get, the better I used to be" --Lee Trevino

  4. #4
    Senior Member sprockets's Avatar
    Join Date
    Jul 2002
    Location
    Toronto, Ontario
    Posts
    161
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Great news, thank you. I picked up the bike last night, the over locknut dimension looks like it's just a hair under 110 mm. Any opinions on what the max OLN dimension I can use without cold setting? I should mention that this is on a 20" wheeled bike so the rear fork is shorter than normal.
    *************************
    As god as my witness, I thought turkeys could fly

  5. #5
    rebmeM roineS JanMM's Avatar
    Join Date
    Jan 2006
    Location
    Indiana
    My Bikes
    RANS V3, RANS V-Rex, RANS Screamer
    Posts
    11,451
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    track-style horizontal dropouts should be ideal for your project

  6. #6
    Senior Member jjciiijs's Avatar
    Join Date
    Mar 2007
    Location
    CO....Hetchins MO, Merlin XL, Trek, Klien, Specialized, Kestral, Bataglin, Guerciotti, Bianchi, Schwinn, Colnago Geo, Miele, Contini, Feggin, Cannondale, Lemond, Ciocc, Giant, Rossin
    My Bikes
    Hetchins MO, Merlin XL, Trek, Klien, Specialized, Bataglin, Guerciotti, Bianchi, Schwinn C19, Colnago Geo, Miele, Contini, Feggin,Cannondale, Lemond,Ciocc, Giant, Rossin
    Posts
    384
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I do not see you having to weld or soder anything. There are cable housing holders that clamp around tubes and you can run the housing to the hub. or you can use zip ties to hold the housing
    Jeff
    Square wheels need not apply

  7. #7
    Senior member Dan Burkhart's Avatar
    Join Date
    Oct 2004
    Location
    Oakville Ontario
    Posts
    4,842
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by sprockets View Post
    Is it possible to just solder the parts necessary for the gear cable to the frame or will it not be strong enough?

    This is a pic of the bike I will be converting:

    You did not specify which hub you are looking at, but given the constraints of your dropout spacing, you are probably best to go wit Sturmey Archer. The 8 speed non braked version is 124mm, but I think I remember Sheldon saying that he narrowed one down considerably by using skinny nuts and spacers.
    Gearing wise, the SA is a good choice for small wheel bikes, as gear 1 is direct, and the rest are overdrives. This means you can achieve normal speeds without an oversize chainring.
    I would suggest, however that you consider the SA SRF5 5 speed hub. It has a decent ratio range, and in the 171.2 mm axle version, has an OLD of just 113.7 mm. I installed one of these in my commuter, and I have been very happy with it.
    Cable attachment is simple, as the cable stop is on a bracket fastened to the axle.
    http://tinypic.com/fullsize.php?pic=...&capwidth=true
    As for routing the cable from shifter to cable stop, zip ties work just fine.
    This one has direct in the middle of the range, so it should work with your current chainring.
    Gearhubs demystified and other cool stuff.


    Rule #12: The correct number of bikes to own is n+1

  8. #8
    Senior Member
    Join Date
    Feb 2001
    Location
    England
    Posts
    12,203
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    In the olden days, braze-ons (ie silver soldered additions) were for high end bikes. Everday machines used clamp-on cable guides and stops. You can still pick these up from some vintage/small-parts places.
    eg
    http://www.theoldbicycleshowroom.co....pair-382-p.asp
    http://www.firstflightbikes.com/shifters.htm
    http://loosescrews.com/index.cgi?c=C...d=430630720109

  9. #9
    Broom Wagon Fodder reverborama's Avatar
    Join Date
    Jul 2006
    Location
    Minnesota
    My Bikes
    Fuji Supreme; Fuji Royale; Schwinn Varsity; Nishiki International; Schwinn Premis, Falcon Merckx
    Posts
    1,165
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I use colored zip-ties on mine. Works great.

    My dropout spacing was 126, the hub was 130 so I just spread it. Rode it like that for a year and it worked fine. Cold set the frame to 130 a couple of months ago. Still works great but changing tubes on the rear wheel is a bit easier now.

  10. #10
    tcs
    tcs is offline
    Palmer tcs's Avatar
    Join Date
    Mar 2007
    Location
    Parts unknown
    Posts
    4,142
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    The Sturmey-Archer X-RF8 model IHSFXDCSAA1 uses a 155mm long axle and has a factory OLD of 116mm. If you gently discussed acceptance of this hub with the pictured frame, I doubt you'd have to do any cold setting.

    HTH,
    TCS
    "When man first set woman on two wheels with a pair of pedals, did he know, I wonder, that he had rent the veil of the harem in twain? A woman on a bicycle has all the world before her where to choose; she can go where she will, no man hindering." The Typewriter Girl, 1899.

    "Every so often a bird gets up and flies some place it's drawn to. I don't suppose it could tell you why, but it does it anyway." Ian Hibell, 1934-2008

  11. #11
    Senior member Dan Burkhart's Avatar
    Join Date
    Oct 2004
    Location
    Oakville Ontario
    Posts
    4,842
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by tcs View Post
    The Sturmey-Archer X-RF8 model IHSFXDCSAA1 uses a 155mm long axle and has a factory OLD of 116mm. If you gently discussed acceptance of this hub with the pictured frame, I doubt you'd have to do any cold setting.

    HTH,
    TCS
    Right you are, and it comes in 28 spoke drilling too, so it's a good fit for a 20" wheel.
    Gearhubs demystified and other cool stuff.


    Rule #12: The correct number of bikes to own is n+1

  12. #12
    Sir Fallalot wroomwroomoops's Avatar
    Join Date
    Jul 2006
    Location
    Helsinki, Finland
    Posts
    5,161
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by sprockets View Post
    Great news, thank you. I picked up the bike last night, the over locknut dimension looks like it's just a hair under 110 mm. Any opinions on what the max OLN dimension I can use without cold setting? I should mention that this is on a 20" wheeled bike so the rear fork is shorter than normal.
    Most gear hubs can be spaced out nicely with washers. Just put the same amount of equal width washers on both sides, and you're golden.

    One thing you didn't mention is, what type of brakes you expect to use? Geared hubs have, very often, roller, drum or coaster brakes. So before you ask: no, you don't need braze-ons for either of those. If it's a roller or drum brake, you can just zip-tie the cable to the frame where necessary.

  13. #13
    Senior Member sprockets's Avatar
    Join Date
    Jul 2002
    Location
    Toronto, Ontario
    Posts
    161
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by tcs View Post
    The Sturmey-Archer X-RF8 model IHSFXDCSAA1 uses a 155mm long axle and has a factory OLD of 116mm. If you gently discussed acceptance of this hub with the pictured frame, I doubt you'd have to do any cold setting.

    HTH,
    TCS

    This looks like my best option, the only problem I have is trying to find one. The LBSs in Toronto claim that their distributors will not order one unless they can be sure to sell 10. I've had trouble finding them online as well.
    *************************
    As god as my witness, I thought turkeys could fly

  14. #14
    Senior Member
    Join Date
    Jul 2003
    Location
    Brooklyn, NY
    Posts
    1,453
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Shoed be able to get one from www.aebike.com

  15. #15
    Senior Member Grand Bois's Avatar
    Join Date
    Mar 2005
    Location
    Pinole, CA, USA
    Posts
    15,100
    Mentioned
    4 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by wroomwroomoops View Post
    Most gear hubs can be spaced out nicely with washers. Just put the same amount of equal width washers on both sides, and you're golden.

    One thing you didn't mention is, what type of brakes you expect to use? Geared hubs have, very often, roller, drum or coaster brakes. So before you ask: no, you don't need braze-ons for either of those. If it's a roller or drum brake, you can just zip-tie the cable to the frame where necessary.
    Adding washers won't make the hub narrower.

Posting Permissions

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