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Ghost shifts while climbing(5 posts)

Ghost shifts while climbingCuervo930
May 10, 2002 6:38 PM
I just got an older Cannondale (late 80's frame) with Campy Record drivetrain (8 speed) given to me. My problem is that when I tried to climb a steep hill, the chain would move down the cassette two or three cogs. Do I have a worn cassette, chain, both or could something else being going on. I had my local shop check over the bike to make sure everything was functional and safe, on the stand the bike shifts perfectly, it only has the ghost shifts when there is alot of pressure on the pedals. I am willing to spend a little money on the bike, so far I only have $35 invested. This will be my foul weather bike, or I may get some narrow cross tires for it as it would be a cheap way to test the waters to see if I could justify buying a cross bike to the wife. Sorry for the ramble, but I am looking forward to tinkering with this bike - just don't want to replace parts that are still good.
How well did they check?McAndrus
May 11, 2002 7:28 AM
Maladjusted derailleurs might do it, or worn out rear derailleur or old cables. Recently I cracked the BB shell on my old Bianchi and it showed just these symptoms.

Whenever I stood to power over a small hill, the bike would shift by itself. If I looked at the chainring while standing, I could see it moving left and right 2-3cm.

I checked as well as I could for cracks in the chainstays, etc. but I couldn't find anything. So I took it to the LBS.

I showed the wrench the movement in the BB and he said, "that's normal." Uh, huh. Then he put it up on his stand, cleaned the chainstays and BB shell completely and got out a magnifying glass. Sure enough, a crack in the bottom of the BB shell.

That was in February. It's now May and I'm still waiting for my warranty replacement frame from Bianchi.
re: Ghost shifts while climbingJoe Nordic
May 11, 2002 8:07 AM
Check out this article by Sheldon Brown:

http://www.sheldonbrown.com/autoshift.html
Thanks for the helpCuervo930
May 13, 2002 4:41 PM
I have been a regular reader of this board, but hadn't posted before. I figured that I could get good advise from everyone, and for that I thank you. The combination of tightening the tension on the friction shifter and lubing the cables has cured my problem. Still holding at only $35 invested into the bike, but that will change this week - new tires and rims. I will be putting on 28mm cross tires (nothing wider will clear front deraileur), but could use a recommendation for the rims & spokes. I am 6'2", 190 lbs and will ride the bike on the road and on smooth singletrack trails.

Again thanks.
re: Ghost shifts while climbingcurlybike
May 11, 2002 3:56 PM
You have a 90% chance that the G springs in the shifter are worn out or broken. Put the chain on one of the largest casette cogs. Reach out with your index finger and lightly tug on the der cable below the cable stop on the downtube. If the cable clicks down in the shifter, the G springs are bad. Branford does repair service on them and Campyonly.com has instructions. If you are in the DC area, I fix them.