adjusting chain/double chainwheel

[aljohn]

I haven't used my bike for several months, it worked perfectly then - I had just rebuilt it. However, for some reason the chain came off when moving on to the large chain wheel, several times. I couldn't see any obvious reason so adjusted it - big mistake! I spent nearly 2 hours adjusting - worked OK when upside down but still played up when ridden. I eventually got it working reliably, but I'm not tremendously happy with it. It's got a noisier, slower change than before. Don't get me wrong, I could live with it but it used to snick gently from one ring to the other. Back to basics, what is the correct procedure when setting up the front changer? This forum has proved so helpful before so I wait with bated breath....
Shimano 600 group set, 39/54 rings
Albert

 

[Peter@vecchios]

I haven't used my bike for several months, it worked perfectly then - I had just rebuilt it. However, for some reason the chain came off when moving on to the large chain wheel, several times. I couldn't see any obvious reason so adjusted it - big mistake! I spent nearly 2 hours adjusting - worked OK when upside down but still played up when ridden. I eventually got it working reliably, but I'm not tremendously happy with it. It's got a noisier, slower change than before. Don't get me wrong, I could live with it but it used to snick gently from one ring to the other. Back to basics, what is the correct procedure when setting up the front changer? This forum has proved so helpful before so I wait with bated breath....
Shimano 600 group set, 39/54 rings
Albert

Biggest cog, small ring. Ensure the FD inner cage is close to the chain(really close). Attach cable tightly. Smallest cog, shift to big ring. Make sure the height of the FD, outer cage is close to the big ring(<1mm) and outer cage is aligned with the chain when in big ring and small cog and then outer limit screw to ensure outer cage is close to chain. Shift to middle of cogset and shift up and down the rings. Remember you have a trim in the big ring.

 

[aljohn]

Biggest cog, small ring. Ensure the FD inner cage is close to the chain(really close). Attach cable tightly. Smallest cog, shift to big ring. Make sure the height of the FD, outer cage is close to the big ring(<1mm) and outer cage is aligned with the chain when in big ring and small cog and then outer limit screw to ensure outer cage is close to chain. Shift to middle of cogset and shift up and down the rings. Remember you have a trim in the big ring.

Thanks Pete, I knew the basics but was unsure mainly the height of the changer to the big ring. In one book it gives 1/4 to 1/2 inch clearance, which I did. But I seemed to recall the gap was much smaller when I last played about with setting up gears (many years ago). You've confirmed my suspicions and I'll re-adjust later this week. Cheers
Albert