Shimano DA-7700 9 spd bar end shifters with Shimano 10 spd cassette?

Quoted message said:

Will this combination work? The rest of the drivetrain is 9 spd
Ultegra. I happened to notice that the
Dura Ace bar end shifters have an extra click, and was wondering if
the extra position could be used
to index on a 10 spd cassette. I just went from a 12-23 to a 12-25
cassette, and notice the wider
spacing of the gears. I'd like to get that 25t cog without having
bigger jumps, and 10 speed seems like
a good way to do it. It would be nice to just buy the 10 speed
cassette and not have to change
the bar end shifters, too.

I know the extra click you're referring to, and though I haven't tried
it, I'd be very surprised if enough cable got pulled there to allow
this to work. It would be pretty easy to measure how much cable got
pulled in the extra click. Even if it was remotely close to the normal
pull, you'd also need to do something to modify the cable/derailer
movement ratios to make the shifter work with 10 spd spacing.

Quoted message said:

Will this combination work? The rest of the drivetrain is 9 spd
Ultegra. I happened to notice that the
Dura Ace bar end shifters have an extra click, and was wondering if
the extra position could be used
to index on a 10 spd cassette. I just went from a 12-23 to a 12-25
cassette, and notice the wider
spacing of the gears. I'd like to get that 25t cog without having
bigger jumps, and 10 speed seems like
a good way to do it. It would be nice to just buy the 10 speed
cassette and not have to change
the bar end shifters, too.

It would work only with the shifters set in the friction mode, not in
the indexing mode.

Quoted message said:

Will this combination work? The rest of the drivetrain is 9 spd
Ultegra. I happened to notice that the
Dura Ace bar end shifters have an extra click, and was wondering if
the extra position could be used
to index on a 10 spd cassette. I just went from a 12-23 to a 12-25
cassette, and notice the wider
spacing of the gears. I'd like to get that 25t cog without having
bigger jumps, and 10 speed seems like
a good way to do it. It would be nice to just buy the 10 speed
cassette and not have to change
the bar end shifters, too.

I have some DA-7700 9 speed bar ends on my TT bike. They do not work
with my 10-speed Ultegra cassette. I didn't monkey with any
adjustments, I just popped in the wheel so see, so your mileage may
vary.

Joseph

Quoted message said:

Will this combination work? The rest of the drivetrain is 9 spd
Ultegra. I happened to notice that the
Dura Ace bar end shifters have an extra click, and was wondering if
the extra position could be used
to index on a 10 spd cassette. I just went from a 12-23 to a 12-25
cassette, and notice the wider
spacing of the gears. I'd like to get that 25t cog without having
bigger jumps, and 10 speed seems like
a good way to do it. It would be nice to just buy the 10 speed
cassette and not have to change
the bar end shifters, too.

9s shifters shift 9s spacing, not the much closer together 10s. Not
the same as XT top mounts where the the spacing 7 to 8 was much more
alike.