Originally Posted by
higgit
Hi,
This is my first post. I am a retiree who has become addicted to cycling. My wife calls me obsessive; she's right.
I have a 2006 Specialized Sequoia Elite. My age is 68 and I do 50-100 mile club rides in a hilly area with hopes of doing a trip like Mountains-to-Sea in NC or the Blue Ridge Parkway before I have to use a walker.
I have had difficulty with long, over 10% climbs so I replaced the 11-25 (9 speed) that came with the bike with a 11-32 Mtn bike cassette (Deore) to go with the 52-42-30 Sugino triple crankset.
This has made climbing significantly easier and I am very happy with the extreme 30/32 ratio. However, what I gained in climbing, I have lost in ability to keep up with the better riders in my club because the gap between (cassette) gears has gone way up. I realize that I need the close ratios of a 12-23 cassette.
So, I thought: why not install a 44-32-22 mtn bike crankset (Deore XT) with a 12-23 cassette. That way I would have both the hill climbing capabilty (22/23 extreme overall ratio) and the close ratios for level paceline riding. What I would give up is the higher speeds from the 52 wheel, which I am happy to do because I seldom, if ever, achieve (level, wind-free) speeds of over 22-24 mph. And, going downhill for me is more about applying brakes than cranking.
First, technically and mechanically, can one use a mtn bike crank (Deore XT) on a Sequoia frame (9 speed)? Any issues with bottom brackets, etc.?
Second, will it work? Will I meet my twin objectives of: climbing capability and close ratios? Has anyone done this?
Any help will be greatly appreciated. Thanks. Ted
Technically... some things to think about, but no problems at all:
- You may need to change the bottom bracket to match the new crankset, but practically all modern frames (road or MTB) use the same BB threading, so there's no issue there.
- You'll certainly need to adjust the front derailer height to match the new crankset. You may have to actually replace the FD as well... many people will tell you this is a must but I have found you can make practically any triple FD work with practically any triple cranks in practice
- You'll probably have to remove a few links from your chain to get rid of the slack from the smaller chainrings. Easy.
As to whether it will achieve the desired effect... hard to say. You're proposing to switch from a 30/32 low gear to a 22/23 low gear. That means your LOW GEAR will actually get
slightly higher!!! (Compare the ratios.) So this change certainly won't improve your low-end gear for those steep hills.
As for close-spaced gearing on the flats: between the 11-25 cassette and the 11-32 cassettes, you lost the 15T and 17T cogs. It's likely that you used one of those a lot and that "perfect" gear combination (for you) is what you're missing with the wider cassette. You might consider getting a custom cassette with those cogs included... say Sheldon Brown's
Century Special: 13 14 15 17 19 21 24 27 30. That seems like it might be a decent compromise, and would be a simpler and less expensive solution that replacing your cranks, BB, and possibly front derailer. What do you think?