Colnago Master Gear Problem

Velonutter
Velonutter Posts: 2,437
edited April 2013 in Workshop
Took my master out for it's first ride on Saturday, it's running Athena 11s with a 29/12 on the back and a 50/34 on the front.

Problem is that when I effectively cross the gear, i.e. 50/29, the chain drops down to the 34 after a few turns.

BTW I always cross the gears and never have a problem on any of my other bikes.

I've double checked the stops and tried again on yesterdays Audax, but still to no avail.

Anyone got any ideas as I'm stumped on this one, everything looks perfectly in line.

Any advice would be most welcome.

Comments

  • Chain too short ?
  • Velonutter
    Velonutter Posts: 2,437
    Chain too short ?

    Thanks, I'll do a picture tomorrow, but I'm fairly sure it's perfect as it was too long and catching on the cage, so I dropped one link, but maybe if I fitted a long chain, can I adjust to correct using the B screw?
  • FatTed
    FatTed Posts: 1,205
    I suspect it maybe because the Master has short chainstays so the angle Big/Big is more acute than ideal.
    The minimum recommended chainstay length for Shimano and Campagnolo is 405 mm
    My MXL's chainstay is about 405 mm.
  • Velonutter
    Velonutter Posts: 2,437
    Thanks Ted, centre of the BB to the spindle is 410mm, I might adjust the fork adjusters some more to give me even greater distance and see how that goes.
  • styxd
    styxd Posts: 3,234
    Don't cross chain!!!!
  • Velonutter
    Velonutter Posts: 2,437
    styxd wrote:
    Don't cross chain!!!!

    Easy to say that, but I do it on all my other bikes and never have a problem and I prefer that style of riding, don't like to be defeated with a challenge, so I have got to fix it.
  • FatTed
    FatTed Posts: 1,205
    I can cross chain with 50/27 I use a KMC chain. I have another bike now with longer chainstays so
    don't ride the Master any more. (I guess the angle is more obtuse than acute!)
  • on-yer-bike
    on-yer-bike Posts: 2,974
    Do you run a 29 on your other bikes?
    Pegoretti
    Colnago
    Cervelo
    Campagnolo
  • Velonutter
    Velonutter Posts: 2,437
    Do you run a 29 on your other bikes?

    Yep have done and no problem, I switch between a 27 & 29 if it is a hilly course.
  • thegreatdivide
    thegreatdivide Posts: 5,807
    Velonutter wrote:
    styxd wrote:
    Don't cross chain!!!!

    Easy to say that, but I do it on all my other bikes and never have a problem and I prefer that style of riding, don't like to be defeated with a challenge, so I have got to fix it.

    I’m almost certain that the front mech on all Campagnolo 11-speed groupsets is designed to allow for cross chaining. It’s quite wide compared to the 10-speed mechs.

    I’ve got Athena 11-speed on my Master with a 50/34 12/25 and the shifting is flawless - but this’ll be down to the chap I got to build the bike at my trusty LBS and not my pathetic skills! :lol: