Front derailer

brettjmcc Posts: 1,361
edited June 2010 in Workshop
Question for the knowledgable types. I came back from a holiday and was cleaning a bike a bought second hand after doing a couple of rides on it.

I went out for a ride last night, and the derailer seems to have moved slightly so that I can hear the chain rubbing when it is in the higher gears on the bottom ring. I also noticed that when switching back to the large ring that I had to be in a higher gear. If I was in a lower it didn't switch across as well.

It was fine before I cleaned it. I was getting in the derailer with a toothbrush to get dirt etc out.

The setup is Ultegra. Any advice for readjusting? Thanks
Quintana Roo Cd01
Project High End Hack
Cannondale Synapse SL (gone)
I like Carbon


  • Hugh A
    Hugh A Posts: 1,189
    Dirt affects the set-up of deraileurs a lot and freeing it up may have affected the indexing. do you have a barrel adjuster where the cable from the levers joins the frame? This is where you would adjust the front indexing as it changes the effective cable length. Sometimes there are in-line ones like a small solid tube on the flexible gear cables near the levers.

    If you have none of those then you might have to do it using the clamp bolt. from what you say it now may need tightening up a bit and this can be done with the clamp bolt when the cable is slack (in small ring at front) but this is more trial and error and can damage the cable a bit what with clamping it and loosening it off if you need to do it several times.
    I\'m sure I had one of those here somewhere