Advertise on Bikeforums.net



User Tag List

Results 1 to 4 of 4
  1. #1
    Junior Member
    Join Date
    Oct 2008
    Location
    Oregon, WI
    My Bikes
    2007 Trek 2100
    Posts
    16
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Sync Timing chainring on drive side?

    I know you can set up a tandem with a single-sided drive. My question is whether you can use older Shimano cranks (octalink or square taper) and put a third chainring on the outside of the large chainring (using spacers that John allen has on his tandem page). Would the Q factor allow it? 90s Campagnolo cranks? Could I fit a chainring on the inside of the front cranks and fit it to the stoker's cranks (on a front drive tandem since a chainring in back might hit the chainstays)? Any other suggestions so I could build my tandem for cheap(ish)?

  2. #2
    Senior Member Retro Grouch's Avatar
    Join Date
    Feb 2004
    Location
    St Peters, Missouri
    My Bikes
    Rans Enduro Sport, Hase Kettweisel Tandem, Merin Bear Valley beater bike
    Posts
    23,602
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Try using a triple crankset in the rear and a double crankset with a 30t ring on the inside position in the front.

  3. #3
    hors category TandemGeek's Avatar
    Join Date
    Jan 2002
    Posts
    7,151
    Mentioned
    0 Post(s)
    Tagged
    1 Thread(s)
    Quote Originally Posted by storunner13 View Post
    Would the Q factor allow it?
    Your only real constraint is travel limits of the front derailleur and picking bottom brackets that give you the ability to off-set the axle to support what ever configuration you choose to use for your same side drive.

    There are just too many different ways to make this work. Frankly, if you're simply trying to do a tandem drive train on the cheap you can also cannibalize three standard cranks -- one triple and two doubles -- to come up with a cross-over crankset by simply re-taping the threads of the doubles to flip the rights to left and one left to right.

  4. #4
    headtube. zzyzx_xyzzy's Avatar
    Join Date
    Sep 2008
    Posts
    804
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Putting a sync chainring outboard the outer ring works on some cranksets and not others. Only experiment will tell. Mountain bike cranksets are more likely to work because the crankarm swings wide early to clear smaller chainrings. Also, using narrow 9 or 10sp chain for the sync can buy an extra fraction of a mm for clearance.

Posting Permissions

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