Merry Christmas everyone!
I've been retooling my drive train on my vintage road bike. After my upgrades, my rear derailleur makes a clicking noise on the largest two cogs (23 and 26). I've checked the pulleys for wear, the derailleur hanger alignment, and the b-stop screw adjustment. Everything looks good so I was wondering if my chain line could be a problem. My shifting is crisp and works well other than the clicking on the largest rear cogs - it clicks at various degrees using either my 39 or 53 front chain ring.
Here is my setup:
- Campagnolo Chorus Crank (1988) originally for 7 and 8 speed Index Shifting with 39/53 chains
- Campagnolo Chorus Bottom Bracket (1988) - Italian Tread 70/110 spindle
- Campagnolo Chorus 9 speed rear derailleur and brifters (1997)
- Campagnolo Chorus 9 speed cassette 13-26 (this is New Old Stock)
- New KMC 9 Speed Chain shortened using Campagnolo's longest length method
So my main question is that from looking at the literature, the older Campagnolo 7/8 speed setups had a 45mm chain line with a 110mm bb spindle length. It appears that all of the newer 9 speed and up chain lines are 43.5 - with a 102mm bb spindle length. Can this difference (i.e. the 45mm on my 8 speed vs the 43.5 on 9 speed cranks) cause the clicking issue? I am thinking about getting a Phil Wood or Campagnolo CART bottom bracket that would allow me to adjust my chain line but I wanted to get some feedback first.