|Jamming Campy shifter||UcannotBsirius|
Nov 1, 2003 10:41 AM
|Just over a year ago I bought a new bike with Campag Centaur throughout. A month or two after I got it it fell over whilst stationary in the cellar, onto the righthand side. When I checked it out the only damage I could see was that the replaceable mech hanger was bent, but I adjusted the upper and lower limit screws and tweaked the indexing - it then indexed perfectly. The first few rides the righthand (rear) shifter would jam when trying to shift up the block, the shifter just going solid and refusing to move. After a few rides the problem went away though.
The bike was stored over the winter while I rode my other road bike then I have done about 2,500 miles on this bike over the summer, with no shifting problems at all. Today I did a hilly 60 miler and the righthand shifter was jamming constantly. I had to downshift each time then upshift twice to get the gear I wanted - hardly ideal!!
Any ideas as to what is causing this and how to fix it??
|Sticky thumb button?||flakey|
Nov 1, 2003 1:21 PM
|The most common reason for an ergolever to jam is that the thumb button is stuck, or sticks in the down position. If the thumb button doesn't release, it prevents the shift assembly from shifting up to a lower cog. There are a couple of things that can cause the thumb button to stick: corrosion, either from sweating or salt water, or the rubber hood is preventing it from springing back completely. It is also possible that the thumb button was slightly defective from the factory (pivot a little too tight, so it sticks).
Here are a few suggestions that may help you resolve this yourself: drip a little tri-flow on the thumb button pivot and then work it up and down, LIGHTLY flex the thumb button forward and backwards, like it was a stiff link, at the pivot, make sure rubber hood is out of the way.
Last resort is the thumb button needs to be replaced.
|You did state that your hanger was bent......||Tom C|
Nov 1, 2003 6:37 PM
|so although I can't account for the intermittent operation of your shifter, I don't think the fix was to adjust the rd's limit screws. Your hanger, as you say is replaceable, so my first inclination would be to replace it, have the shop check your rear derailler alignment after replacing as you cannot rule out the rd is possibly slightly bent itself. Somehow I doubt there is anything wrong with your shifter. If you like you could order a new hanger, install and test yourself. If no go, I would replace the derailler as realigning is quite difficult unless you can get new cage parts ( the most likely bent area on a rear derailleur) and rebuild it. Only after eliminating the hanger and rd as a cause of the sticky shifting would I then look at the shifter. Good luck.|
|re: Jamming Campy shifter||BenR|
Nov 2, 2003 11:42 AM
|Regardless of whether your hanger is bent, your shifter shouldn't be jamming. In addition to the other suggestions, you might have a broken shifter post. This supposedly isn't a problem on newer parts but, but maybe it still happened? I would think a broken post could cause binding and so could a broken return spring (they are notorious for breaking). It is probably something you would want to take into your local shop if they have campy experience, that way it becomes their problem and you don't end up with parts all over the place. Even as a poor student, I would consider it $50 well-spent. The link below is where I read about the problem. I also needed my Chorus lever springs replaced at about 17,000 miles. It cost me $50 for parts & labor. You might also want to make sure your B screw adjustment is not way off. If your jockey wheels are too close to your rear cogs, it could prevent you from shifting up to a bigger cog. I'm sure a misaligned hanger/cage doesn't help the situation, best to get all of this fixed properly at the same time. Good luck.