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View Full Version : Downtube ****er compatibility question-

buck-50
07-22-2009, 10:33 AM
So, the guy at the bike shop swears that Dura ace10 speed DT shifters are completely compatible with DA 9 speed cassettes- you just get an extra click.

Anyone have any experience with this?

The shop in question is Yellow Jersey in Madison, so usually he's got pretty solid advice, but just as often there's a hidden "but" that doesn't come out until you get it home and installed...
paulrad9
07-22-2009, 11:09 AM
I am thinking it may be, "....but you have to use friction" :D
buck-50
07-22-2009, 11:11 AM
I am thinking it may be, "....but you have to use friction" :D
And we all know how much fun it is friction shifting a 9 speed cassette... :rolleyes:
nahtnoj
07-22-2009, 11:27 AM
And we all know how much fun it is friction shifting a 9 speed cassette... :rolleyes:

I use friction bar-cons on my 9 speed commuter. Rarely if ever have issues - you get the feel for it quickly.

And yes, that would be the "but" - spacing is different b/t 9 and 10.

7400 and 7700 D/A did have the same spacing though, so he could be confusing 8/9 compatibility with 9/10 compatibility.
dd74
07-22-2009, 03:28 PM
And we all know how much fun it is friction shifting a 9 speed cassette... :rolleyes:
I just completed this mod on my old Colnago: adapted a 9-speed Ultegra cassette to the friction shift system. It's by far the best modification I've done to the bike. The shifts are easy and very close. I barely have to move the shifter to go from gear to gear. It's brought new life to my 25-year-old bike. :beer:
goonster
07-22-2009, 03:34 PM
And we all know how much fun it is friction shifting a 9 speed cassette... :rolleyes:
I friction shifted a 9 sp cassette for 1260 kms, and it did not diminish the fun! :banana:
dd74
07-22-2009, 03:36 PM
I think it's more fun. It's fun to the point where I wonder if I wasted money on index shifting/brifters.
buck-50
07-22-2009, 05:08 PM
OK, fine, I suck. :)
my experience with friction+bar-ends+9 speed was that the cogs were so close together that it made it hard to shift just one cog at a time, and shifting while climbing could be sketchy.

But hey, maybe friction shifters are the way to go here...

Thanks for the input!
dd74
07-22-2009, 06:57 PM
Well, my shifters are on the DT, not on the bar ends. So that's where I'm coming from with my experience.
tmessenger
07-22-2009, 09:00 PM
DA 9 sp shifters pull 2.5mm of cable and DA 10 sp shifters pull 2.3mm of cable, 9 sp cassette cogs are 4.35mm on center and 10 sp are 3.95mm so I'd say not a good match, iffy at best.
JD Smith
07-24-2009, 04:24 AM
OK, fine, I suck. :)
my experience with friction+bar-ends+9 speed was that the cogs were so close together that it made it hard to shift just one cog at a time, and shifting while climbing could be sketchy.

But hey, maybe friction shifters are the way to go here...

Thanks for the input!

Same experience here. I tried it out for a year and it got annoying. I could see how it wouldn't be such an issue with 5,6, or 7 speeds, but with nine, it seemed like just a mm off with the lever an I'd hear clicking. I rarely got it right the first time and was always "trimming".
Besides the fact that the index worked perfectly.
dd74
07-25-2009, 04:22 AM
Same experience here. I tried it out for a year and it got annoying. I could see how it wouldn't be such an issue with 5,6, or 7 speeds, but with nine, it seemed like just a mm off with the lever an I'd hear clicking. I rarely got it right the first time and was always "trimming".
Besides the fact that the index worked perfectly.
It just takes practice. But yeah, if the index shifting is working, why bother in the first place.

JD - great FSF quote. Very true, too.
Marcusaurelius
07-25-2009, 03:24 PM
I remember 7 speed friction shifting was pleasant but when I briefly tried friction shifting with 9 speed and quickly went back to index (not so much fun).
John M
07-25-2009, 04:32 PM
7400 and 7700 D/A did have the same spacing though, so he could be confusing 8/9 compatibility with 9/10 compatibility.


Just to clarify....

7400 and 7700 did not have the same cassette spacing, but the same 9s-compatible shifters worked with both RDs because the shift ratios of the derailleurs were different. Thus a shimano 9s shifter with a DA 7400 RD was compatible with 8s spacing, and the same shifter used with a DA 7700 RD was compatible with 9s. Lots of people misunderstood why the bar end shifters were labelled to be compatible with both 7400 and 7700 RDs