> I think the subject line may intrigue and he can answer at his own
> leisure. I don't see a custom 10 speed cassette offered by Harris, so
> I'm guessing it's not possible. It would be interesting to know why it
> won't work.
I get asked this a LOT, so I have prepared a boilerplate response to
the frequent emails I receive, viz.:
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We do lots of custom cassettes in 9-, 8- and 7-speed. Most of these
custom cassettes involve adding a larger rear sprocket for a lower
gear.
Unfortunately, the design of Shimano's 10-speed cassettes features a
recess in the spider mount for the larger sprockets, allowing the
innermost sprocket to be closer to the spokes than the shoulder on the
Freehub body.
This makes it impossible to substitute a different low-gear (largest)
sprocket. As a result, we are unable to offer custom 10-speed
cassettes, at least at this time.
The largest 10-speed sprocket currently available from Shimano is 27
teeth, and there is no way for us to install a larger one on a 10-speed
system.
However--all is not lost. Most 10-speed setups will allow you to
install a 9-speed cassette, and these are available in a much wider
range of useful gears. The 10-speed shifters will index a 9-speed
cassette if you use the "alternate cable routing" shown at:
http://sheldonbrown.com/derailer-adjustment.html#alternate
Note, if you have a Dura-Ace 7800 hub, or a "10-speed" Ultegra 6800
wheel, those will _not_ accept a 9-speed cassette. Other
Shimano-compatible hubs will work with 8-, 9- or 10-speed cassettes.
9-speed cassette options are shown at
http://harriscyclery.com/9.
If you want to go for a sprocket bigger than 30 teeth, you will likely
need to replace the rear derailer, but those are not expensive.
All the best,
Sheldon
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Sheldon "Answers Emails With A Couple Of Mouse Clicks" Brown
+----------------------------------------+
| Millions of people say I exaggerate. |
| --Marty Gasman |
+----------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com