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  1. #1
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    Old Ibis Mojo(1993) New Parts

    Could some one with more knowledge help me with a component upgrade quesetion? I have a 1992/1993 Ibis Mojo and have been in the process of upgrading many of the components. The one thing I don't want to upgrade is the rear cassette (7 speed) or the thumb shifters and deraileurs. All this is Shimano Deore of the 1992/1993 vintage. I would like to upgrade the cranks though. My question is could I install the new Shimano XT - M770 XT Crankset HollowTech II - 44 /32/22T and leave everything else alone? Will all the shifting still work (front and back). Thanks for any help you can provide.

  2. #2
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    Nope, won't work so well. The narrower chainring spacing with the new (9 speed) cranks mean you would *have* to use a 9 speed chain. That would actually be OK for the 7 speed rear drivetrain - narrower chains usually still work OK. But your 7 speed front derailleur cage would probably be too wide and not work with the 9 speed crank. If you had 8 speed, you could get away with it. So then you'd need either an 8 or 9 speed front derailleur; and I don't think your 7 speed front shifter would work so well with this front set up. A good bike shop might be able to get you set up with some spacers that you could install on the 9 speed crank. It's not just the spacing, though, 9 speed cranks also position the chainrings slightly more outboard (to the right) than 7/8 speed.

  3. #3
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    The ft shifter is a friction thumbshifter, right? That'll work with anything, as long as your thumb and brain work. Soooooo, then the only question is, Will a chain that shifts well on a 7sp cassette also shift ok and not rub or jump or suck on a 9sp crank. I dunno, I've never tried it. I would try it though.... I bet with an 8 sp chain it would be fine. Shimano's rules are bendable within reason.

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