Originally Posted by
icemilkcoffee
You have two problems:
1. The Dura Ace RD7402 is limited to 26T large cog and the total capacity is also a very limiting 26T. If you want to run larger cogs in the back you have to switch to something like a Deore RD.
2. The RD7402 also is not compatible with non-Dura Ace shifters and vice versa. That 74** generation of Dura Ace does not play well with others.
1. I ran mine with a 12-26 and 53-39 for a total of 28. No problem.
2. This is false. 7402 will work with any Shimano 9 speed shifter to produce 8 speed spacing. Shimano lists that in their manuals.