wphamren said:
I have a 6500 crank (chainrings FSA) and cog set, r600 shifters,and HG93 chain and I want to upgrade my derailleurs to 6700. Shimano states in the FAQ that upgrading 10 speed DA to 9 speed drivetain is a good thing. I have also read that the cage on the 6700 FD is closer to 6500 on velonews. So, anyone have input on wheter or not keeping 9 speed crank, chain and cogs will work with 6700 RD and FD, or do I have to upgrade to another gear I will not use?
What are you trying to do?
If you aren't going to change your shifters, then there is little benefit in changing the 9-speed derailleurs to 10-speed derailleurs.
While some people think that 10-speed Shimano rear derailleurs are mechanically the same as 9-speed Shimano rear derailleurs, it's just not true.
That doesn't mean you can't use a 10-speed Shimano rear derailleur on a 9-speed Shimano drivetrain, but you may find the shifting less precise ...
I use 10-speed Campagnolo shifters with Shimano rear derailleurs ...
With the 10-speed Campagnolo shifters + 9-speed Shimano rear derailleur, the rear derailleur anchoring needs to be hubbub'd at 3 o'clock to achieve 9-speed Shimano indexing ...
If the rear derailleur cable is attached 'normally' to a 8-/9-speed Shimano rear derailleur, then the 10-speed Campagnolo shifters will produce 8-speed Shimano indexing.
With the 10-speed Campagnolo shifters + 10-speed Shimano rear derailleur, I correctly deduced that the rear derailleur cable would be anchored normally to achieve 9-speed Shimano indexing ...
There is an apparent illusion that Shimano 10-speed rear derailleurs are interchangeable with Shimano 9-speed rear derailleurs, and vice versa, which is undoubtedly because Shimano cassettes are so well ramped that they generally continue to shift as smoothly (or, not!) when the indexing is slightly off as when it is on the money.
To correctly use a 10-speed Shimano rear derailleur with a 9-speed Shimano shifter + 9-speed Shimano cassette you will need to use the alternate rear derailleur anchoring at 9 o'clock.
FYI. Other than weight & the quality of the pulley wheels, 105 derailleurs are as good as Ultegra & Dura Ace derailleurs ...
I don't know about Tiagra rear derailleur ... I presume it is closer to the 105 rear derailleur than the Sora rear derailleur.
Generally, Sora-and-below rear derailleurs are decidedly less nice but are functionally equivalent if the "speed" designation is the same as the more expensive Shimano rear derailleurs.
The current '7-speed' Shimano rear derailleurs are functional, but otherwise inferior, and should be upgraded with a 105-or-better or LX-or-better if-and-when they need to be replaced.
The significant difference in Shimano's front derailleurs
IF the "speed" designation is the same is the quality of the clamp and/or anchor bolt.
