Adjacent cassette cog tooth delta - what's the max?

Mixing cogs from a 12/23 cassette and a 12/27 cassette (9 speed):

12:27 = 12, 13, 14, 15, 17, 19, 21, 24, 27

12:23 = 12, 13, 14, 15, 16, 17, 19, 21, 23

Here is the mix:

12:27* = 12, 13, 14, 15, 16, 17... 21, 24, 27

Or, replace the 19, 21, 23 with the 21, 24, 27.

My concern is the 4 tooth difference (or skipping 3 teeth) in going
from the 17 to th 21.

Shimano DA 7700 RD.

Would this work?
--
Marty

On May 26, 10:27*am, Marty wrote:
Mixing cogs from a 12/23 cassette and a 12/27 cassette (9 speed):

12:27 = 12, 13, 14, 15, 17, 19, 21, 24, 27

12:23 = 12, 13, 14, 15, 16, 17, 19, 21, 23

Here is the mix:

12:27* = 12, 13, 14, 15, 16, 17... 21, 24, 27

Or, replace the 19, 21, 23 with the 21, 24, 27.

My concern is the 4 tooth difference (or skipping 3 teeth) in going
from the 17 to th 21.

Shimano DA 7700 RD.

Would this work?
--
Marty

Should work, but if it was me, I'd rather have the 19 than the 16.

On May 26, 11:51*am, Hank Wirtz wrote:
On May 26, 10:27*am, Marty wrote:





Mixing cogs from a 12/23 cassette and a 12/27 cassette (9 speed):

12:27 = 12, 13, 14, 15, 17, 19, 21, 24, 27

12:23 = 12, 13, 14, 15, 16, 17, 19, 21, 23

Here is the mix:

12:27* = 12, 13, 14, 15, 16, 17... 21, 24, 27

Or, replace the 19, 21, 23 with the 21, 24, 27.

My concern is the 4 tooth difference (or skipping 3 teeth) in going
from the 17 to th 21.

Shimano DA 7700 RD.

Would this work?
--
Marty

Should work, but if it was me, I'd rather have the 19 than the 16.- Hide quoted text -

- Show quoted text -

Thanks and I hear ya on the 19. I like the 19 with the 53/39
chainrings. But, with a 50/34 I still pretty much get that 19 with
the 17. The 21, 24, 27 would be for when it really turns upward for a
while.
--
Marty

Marty wrote:
Mixing cogs from a 12/23 cassette and a 12/27 cassette (9 speed):

12:27 = 12, 13, 14, 15, 17, 19, 21, 24, 27

12:23 = 12, 13, 14, 15, 16, 17, 19, 21, 23

Here is the mix:

12:27* = 12, 13, 14, 15, 16, 17... 21, 24, 27

Or, replace the 19, 21, 23 with the 21, 24, 27.


Aren't the large cogs held in a carrier? Are only the three biggest on
the carrier?

Anyway, I've never missed the 16T on similar cassettes.

Art Harris

From: (Marty)

Mixing cogs from a 12/23 cassette and a
12/27 cassette (9 speed):

12:27 = 12, 13, 14, 15, 17, 19, 21, 24, 27

12:23 = 12, 13, 14, 15, 16, 17, 19, 21, 23
Here is the mix:

12:27* = 12, 13, 14, 15, 16, 17, 21, 24, 27

Or, replace the 19, 21, 23 with the 21,24, 27.

My concern is the 4 tooth difference (or
skipping 3 teeth) in going from the 17 to
the 21.

Shimano DA 7700 RD.
Would this work?
--
Marty

I have a Sh. seven cog cassette built with a 12-14-17-20-24-28-34 combo,
and even on the 6 tooth jump at the low end I get crisp snappy shifts,
even uphill. Without any factory worn teeth or handicap ramps on the
cogs either (Sh. Deore LX and bar-con shifters).

Hope this quells your fears. :-3)

- -
Compliments of:
"Your Friendly Neighborhood Wheelman"

If you want to E-mail me use:
ChrisZCorner "at" webtv "dot" net

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"Art Harris" wrote in message
...
Marty wrote:
Mixing cogs from a 12/23 cassette and a 12/27 cassette (9 speed):

12:27 = 12, 13, 14, 15, 17, 19, 21, 24, 27

12:23 = 12, 13, 14, 15, 16, 17, 19, 21, 23

Here is the mix:

12:27* = 12, 13, 14, 15, 16, 17... 21, 24, 27

Or, replace the 19, 21, 23 with the 21, 24, 27.


Aren't the large cogs held in a carrier? Are only the three biggest on
the carrier?

Yes they are at least on a Shimano Ultegra 12/27

To answer the OP I would say you should be ok. I have recently bought a 32
(see my earlier post news stuck it behind a 12/27 dropping out the 14 to ride a couple of very hilly
sportives and it has shifted perfectly with my standard Ultegra rear mech
with only a minor adjustment of the B screw to clear the 32. Although I
would never use it except by accident it will shift quite happily onto the
32 when I am on the 53 up front. So thats handling a 5 tooth jump from the
27 to the 32 on either the 39 or the 53 up front.

It would appear that if your rear mech is set up properly then at least an
Ultegra will cope with a much wider range of sprokets than the spec would
have you believe. Armed with a sprocket removal tool, a chain whip and a
handful of sprokets it takes less than 5 minutes to reconfigure your
cassette to match the profile of any event you chose to ride even down to a
corn cob for time trials. I am not sure how the chain likes this type of
mixing and matching but I am sure time will tell!!!!

Graham

Marty wrote:

Mixing cogs from a 12/23 cassette and a 12/27 cassette (9 speed):

12:27 = 12, 13, 14, 15, 17, 19, 21, 24, 27

12:23 = 12, 13, 14, 15, 16, 17, 19, 21, 23

Here is the mix:

12:27* = 12, 13, 14, 15, 16, 17... 21, 24, 27

Or, replace the 19, 21, 23 with the 21, 24, 27.

My concern is the 4 tooth difference (or skipping 3 teeth) in going
from the 17 to th 21.

Shimano DA 7700 RD.

Would this work?

I can't speak for what does or does not work with DA, because I can't
use weak parts and I won't use overpriced parts.

I can say that most of my derailleur bikes use a 7-speed freewheel
that features a 24t-34t jump at the big end. They all work fine.

Chalo