I have Campy Veloce on my 6 month old steel Lemond Sarthe and in the last month , the damn thing wants to upshift , particularly when I cross chain in 53/25-23-21.
I've had three differnent mechanics look at it and they just fiddle with the cable tension. When they test it on the stand , it shifts pretty good and then on the road it's a different matter under hammering conditions. I even gobbed some grease on the cable guide under the BB as per Sheldon Brown's recommendation. Still doesn't help.
Do I need a new cable, or does the rear derailleur need to be taken apart? Would a higher level grade of Campy help like Chorus or Record? Hep me pleeze!