Steelman54 

Been searching around to figure this out.

My left shifter (front derailleur) shifts fine in either direction at least as far as chain movement from one chainring to the other goes.

However, when using the thumb lever to drop to the small chain ring the chain moves fine; but on at least 50% of the shifts to the small chainring, the thumb lever seems to need anywhere from 1 to 3 clicks before it is home. If this isn't done the shifter won't let me go up to the big chainring. Not sure how clear this is, but at times the shift lever won't actuate until I hit the thumb lever again even though it seemed like I pressed as many times as needed to get it all the way home. Any thoughts on this problem?

Best guess says it's time for an overhaul.

The shifters, which I bought new around 2008 are Centaur 10 speed Ergopower shifters, which I believe means they can be rebuilt. However, I'm not 100% sure on this as this is around the time Campag mixed things up a bit. Thoughts on how to know for sure would be great.

Thanks.

Mike

FBinNY 

Midsummer Madness.

I named it that BITD when I handled Campy service for the East, and this exact problem happened yearly on schedule.

Basically, it's hot and you're sweting. It drips off your hands and wicks into the thumb lever pivot. Corrosion sets in and makes the pivot too stiff for the tiny spring to return it to the disengaged position. As long as it stays engaged, you cannot shift.

Usually, the fix is a drop of oil, and working the pivot for a few minutes until it's action is free.

Extreme cases were rare, but could call for a new thumb lever module.

Steelman54 

FBinNY,

Thanks for the info on this. Will try and get a drop of oil, I assume, in at the thumb lever pivot. Weird it's never happened before, but I'm riding this bike less, so maybe it got sticky/rusty. However, if this fixes it, I'm very cool with it.

mpetry912 

I was going to say maybe the spring had taken a set however introducing some lubrication is a great idea.

I turn the bike upside down in the stand and spray in a dry-film lube.

Seems to work well

/markp

KerryIrons

[QUOTE=mpetry912;22985485]I was going to say maybe the spring had taken a set /QUOTE]

Ask anyone knowledgeable in material science: unless extended beyond their range, springs don't take a set. As to the OP's problem, it seems perfectly reasonable that 15 year old shifters might need lubrication. I would try to get out the old grease (wiping or spraying solvent) and re-lube everything.

FBinNY 

I agree ----- Springs do not take a set.

However I disagree about the need to worry about internal lubrication. Nothing indicates it needs it, and it may make things worse. Oil or grease in the wrong area can worsen the levers floating overshift and recenter system.

Steelman54 

I've read about not greasing everything in these types of shifters, be it Campy or Shimano. Will try to get a drop of oil in there at the thumb shifter pivot and hope it does it.

FBinNY, if it comes to it, are these the rebuildable shifters.

Thanks,

MIke

FBinNY 

My first rule of repair is to diagnose the problem, then fix that without causing complications.

Your lever shows classic signs of a sticky thumb lever pivot. Failure to engage when pressed and/or failure to disengage when released. Focus on that and don't look for more grief.

Steelman54 

Update on this, and I will state up front I should have looked first. Anyhow, a drop or of oil seemed to improve the thumb lever action, shifting seemed good with a nice click. However, it would still hang up and need an extra push.

Since I pulled the lever hood back leaning over and looking at the other side I quickly noted the cable was unraveling, a couple of strands prevented the mechanism from getting home so to speak.

Ordering up a couple of derailleur cables and problem should be gone.

Steelman54 

New cable installed, shifting is perfect.

nomadmax 

For future issues, Roger at International Pro Bike Shop in Bellbrook rebuids all my ergo power levers. He does a great job. I'm guessing he might be local to you as well.

Steelman54 

nomadmax, good info, Yes I know I-Pro. Roger helped me out a few years back by checking my Waterford fork for me. Did not know he does the rebuilds.