I have Shimano 10-Speed Cassette, 11-25T on my bike right now.. I'm getting KILLED on the hills. would a 12-27 Dura Ace 9sp cassette work on my bike as i could get it used for a good deal or should i just get the Shimano Ultegra 10 Speed Cassette 12/27.


thank you guys for all the help.

patrick

The 9 speed cog spacing is not the same. It won't work. Get the 12-27 Utegra 10 cassette, but don't expect miracles - it's only an 8% lower gear.

You might also try pedaling standing on the steeper hills. Even al old guy like me can pedal standing for 10-15 minutes at a time. When standing, I typically use 2-cogs smaller, like a 21 instead of a 25.

I have Shimano 10-Speed Cassette, 11-25T on my bike right now.. I'm getting KILLED on the hills. would a 12-27 Dura Ace 9sp cassette work on my bike as i could get it used for a good deal or should i just get the Shimano Ultegra 10 Speed Cassette 12/27.


thank you guys for all the help.

patrick
you can use the alternate cable routing with the 9spd cassette (check sheldonbrown.com for that), but it won't shift quite as smoothly as buying a 10spd cassette. I'd just go with a 105 or ultegra 10spd cassette.
depending on what crank you've got currently, you might be able to get a smaller chainring to help on the hills.

adding linkage to sheldon's page - http://sheldonbrown.com/derailer-adjustment.html#alternate

The 'duh' comment wasn't called for.

The difference between a 25t and a 27t is a little less than the difference between your 23t and 25t cogs.

If the 27 isn't low enough you can get 12-28 clusters from IRD. They also have 10sp clusters in MTB type ranges (i.e. 11-32) if you want really low gears. You'll need a MTB derailleur for that. This setup (using 9sp parts) was common on hilly rides in my area before compact 110mm BCD cranks came back into vogue.

You might be able to go larger than 27 cog without a new rear derailleur. And you can probably put a 38 tooth on the front for a small benefit over the 39. Then there is a compact crank option.

See Capacity entry
http://sheldonbrown.com/gloss_ca-g.html#capacity

http://www.sheldonbrown.com/harris/k7.html

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