|Campy Drivetrain +Shimano comp Wheelset HELP||Lozes|
Aug 29, 2003 4:16 PM
|I am running a campy drivetrain with a shimano compatiable wheelset(Shimano cassette 9 speed).I can not get it to shift smooth (ghost shifts, etc).I hear it can be done.Any hints? Hate to have to get rid of my Velomaxs. Thanks|
|9 speed Campy? (nm)||TFerguson|
Aug 29, 2003 4:21 PM
|YES ,9 speed Campy? (nm)||Lozes|
Aug 29, 2003 8:04 PM
|They are not the same spacing...||TFerguson|
Aug 30, 2003 12:15 PM
|but close enough that a lot of people do it. The adjustment will always be harder to maintain, but do-able.
|re: Campy Drivetrain +Shimano comp Wheelset HELP||Derf|
Aug 29, 2003 6:16 PM
|I just did this on my bike. 9 speed Veloce shifters and derailer(sp) with 105 hubs and sram 9 speed cassette. I did not have any problems. But, I spent alot of time setting up the high and low limits per the instructions at Parktools.com. From there it was easy dialing in the shifting using the barrel adjuster at the back of the derailer to change cable tension.
|here's what is happening...||C-40|
Aug 30, 2003 12:30 PM
|The cog spacing on Shimano 9 speed is 4.32mm. Campy 9 speed cog spacing is 4.55mm.
If the campy derailleur moves 4.55mm eight times, it travels 36.4mm. The center of the Shimano 9th cog is located 34.56mm from first cog (4.32 x 8). The difference is 1.84mm. 1.84mm divided by 4.55mm is .40 or 40%. If the derailleur is centered on the first cog, like normal, on the 8th shift the campy derailleur would over-travel by 1.84mm. It would be 40% off location, with the chain trying to jump off the largest cog (and perhaps into the spokes), unless restricted by the limit screw.
The best shifting that you can get requires the rear derailleur to be aligned as closely as possible on the center cog, to distribute the error equally between up shifts and down shifts. The accumulative error will still be 20% in both directions, on the 4th shift. The limit screws can be used to help reduce the overtravel on the 4 shift up or down from center. When adjusted properly, the first shift on either side of the center cog should be pretty decent, with the error reducing the acuracy on each progressive shift up or down from the center.
A better solution is to buy a special cassette from excel sports, which has the proper spacing ($100) or stick with all campy parts.