Quoted message said:
Quoted message said:I have an old Cannondale road bike that I can't afford to replace. But
my knees need lower gears. Is it still possible to replace the 7-speed
cogset with an 8-speed. And would it be possible to put a compact
crankset on the bike? I'm not sure what's changed in the past 15
years...
A usually reliable source replied:
Quoted message said:
If the freehub is recent enough, yes, the 8-speed cassette will slip
right on.
It will slip on, and it will also slip off, because a 7-speed Freehub
body is not long enough to hold 8 normally spaced sprockets and still
allow the lockring to reach its threads.
It is usually possible to put 8 sprockets of a _9-speed_ cassette onto a
7-speed Freehub, see: http://sheldonbrown.com/k7.html#up7
Quoted message said:If there are threads on the outside of the end of the
freehub, it's definitely not recent enough.
Not necessarily. Many transitional Freehub bodies had _both_ internal
and external threading, so they'd work with either Uniglide or
Hyperglide cassettes. (See http://sheldonbrown.com/k7 for details.)
Quoted message said:... you can get a 7sp cassette that was built for a
touring bike (or an mtb) and swap it on, though you'll almost
certainly need a longer chain
Right. Should always replace the chain when installing a new cluster in
any case.
Quoted message said:and you may need to swap up to a rear
der with a longer cage. That later issue is probably avoidable if you
don't get carried away with putting a pie-plate-sized low gear in the
back.
Pretty much any derailer made in the last 20 years will work with a 28
in back, and almost all will handle a 30.
Quoted message said:Swapping to a compact crank in the front may entail swapping out the
front der, depending on what you've got now.
This could be a problem, onacountta Cannondales often use "braze-on"
front derailer mounts, which may not provide sufficient adjustment range
to let you mount the front derailer low enough for good shifting.
Sheldon "Strictly Speaking, Possibly" Brown
+---------------------------------+
| Is ambivalence a bad thing? |
| Well, yes and no. |
| -- Garrison Keillor |
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Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
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