I keep hearing from various sources that the 2007 Dura-Ace shifters, cassettes, chain, etc. will not be compatible with the current 2006 versions. Can anyone comment as to the truth or this rumor? Thanks!

Hi

If it's going to be an electric STI setup theRD, FD and Shifters probably won't be compatible...

bb.nsmb.com/archive/index.php?t-74249.html

http://www.velonews.com/tech/report/articles/9664.0.html

Wonder if it will happen in 2007.

2006 and 2007 are identical. The "electric" is another story and yet another example of Shimano attempting to answer the question nobody has asked (although Campagnolo is working on electric prototypes also.)

7800 series is still 7800 series

Dura Ace will not change until the 2008 model year, when Shimano apparently have a lot of improvements in store. One of the reported changes will be the ability to upshift two cogs at a time instead of the now standard one.

Have a look at the 2007 XTR for some clues. XTR's crank/bb interface was changed slightly to prevent incorrect loading on the bb bearings, and prevent problems with the pinch bolts on current DA coming from incorrect installation. You can bet that this will show up on 2008 DA too! Also check out the carbon/metal chainrings on the new XTR. That might be something that shows up on new DA. I wouldn't expect carbon cranks though. Shimano is the largest user of carbon fibre in Japan, outside of the Japanese military ( on the fishing and golf sides of their business). That, allied with the fact that Shimano are huge and all-knowing in the ways of forging aluminum ( see the current DA cranks. Competitors are still trying to understand how they forge HOLLOW cranks in aluminum), mean that if Shimano wanted to employ carbon in many of the current trendy places on bikes, they likely would have done it already, especially in the new XTR.

Current DA works really well. It's hard to imagine what they might improve, aside from the aforementioned, aimed at improving reliabiltiy and making the whole setup even more robust.