i have a 2003 cervelo dual and i want to upgrade my bike to dura ace … my bike has a shimano 105 cassette (cogs???) and it is 12-25 … if i change the chain and cassette to dura ace 9 speed 12-25 is that all i have to do? also i just bought zipps and i need a cassette for the rear wheel … should i buy the dura ace cassette and just keep it on my race wheels? confused!!!
105, Ultegra, and Dura-Ace are all compatible and interchangable within 9-speed/cogs (not 10-speed/cogs).
Shimano 105, Ultegra, and Dura Ace are all completely interchangable. Dura Ace cassettes work with 105 derailleurs, and vice versa. Dura Ace shifters work with 105 derailleurs, and so forth
Edit–> Unless you’re really attached to the 12-25, I’d recommend getting a different ratio on the new cassette, like 12-21 or 11-21. That will fill in the gaps in the cluster, at the expense of the really low gears that you may not use in a race. That way you’ll have a couple of options, depending on how hilly the race is.
I just did this. Like someone else said it is all compatible. I have dura cassette on race wheels and 105 on training wheels. I just upgraded cranks, BB’s and derailers to dura ace. It seems smoother. next step is shifters and breaks.
I recently bought a new set of wheels and I picked out a new cassette for it. I had an 11-21 on the old wheel that just didn’t fit my goal riding style (high efficient cadence without speed or power spikes - unless the wind is on my back! :). I wanted to have as few gaps as possible, so I only considered a 13-23 or a 12-21. Both are the only two Shimano cassetes that have an 18 tooth cog (I think). My thought is I will glide between the 17 and 19 gear way more than I would drop down to the 12, so by that reasoning I went with the 13-23.
Whatever choice you make I would recomend looking at an online gear calculater and determining what ratio of gears will work best for you.
Brian