Upgrading 7sp cassette to 8/9?

Discussion in 'Cycling Equipment' started by Tom Williams, Jul 19, 2003.

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  1. Tom Williams

    Tom Williams Guest

    Hi,

    This is probably an oft asked question, but I'm looking at upgrading my old 'winter' bike's 7sp set
    to something a bit more modern, mainly so I can throw some Ergo levers on there.

    At the moment, I have a fairly generic (in that I can't remember what it is) 7speed block on the
    back, with a Mirage '97? rear mech. I understand the rear mech will have to (obviously) be upgraded
    too. The chainset is a Mirage job of the same year, probably '97, (52,42 if that helps at all) and a
    Veloce front mech, again probably 1997. Brakes are Shimano RX100s if that's relevant.

    Now, what do I have to change, am I looking at replacing the whole chainset/cassette/rear hub etc? I
    understand I also need 130mm between rear dropouts to fit these modern hubs in, some pointers on
    where to measure ths from would be much appreciated. The frame is about 6-7 years old, Reynolds
    CR(o)MO tubing.

    Sorry for the incredible vagueness in my post, but this bike has sat in my shed for a long time
    being neglected, I got it out the other day to clean it and decided it needed a little modernising.
    Any advice will be welcomed with opened arms.

    Thanks, Tom
     
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  2. Tom Williams

    Tom Williams Guest

    Oh, that's nice, I thought all the indexing would be off for 7 speed, that's put me in a good mood
    now. The only reason I was looking at a new cassette was for the Ergo shifter ability, I can't put
    up with downtube levers anymore, after riding my other bikes with Ergo levers.

    Handlebar tape eh ;)

    Thanks,

    Tom

    "Sheldon Brown" <[email protected]> wrote in message
    news:[email protected]...
    > Tom Williams wrote:
    >
    > > This is probably an oft asked question, but I'm looking at upgrading my
    old
    > > 'winter' bike's 7sp set to something a bit more modern, mainly so I can throw some Ergo levers
    > > on there.
    > >
    > > At the moment, I have a fairly generic (in that I can't remember what it
    is)
    > > 7speed block on the back, with a Mirage '97? rear mech. I understand
    the
    > > rear mech will have to (obviously) be upgraded too. The chainset is a Mirage job of the same
    > > year, probably '97, (52,42 if that helps at all)
    and
    > > a Veloce front mech, again probably 1997. Brakes are Shimano RX100s if that's relevant.
    > >
    > > Now, what do I have to change, am I looking at replacing the whole chainset/cassette/rear hub
    > > etc? I understand I also need 130mm between
    rear
    > > dropouts to fit these modern hubs in, some pointers on where to measure
    ths
    > > from would be much appreciated. The frame is about 6-7 years old,
    Reynolds
    > > CR(o)MO tubing.
    >
    > If you want to do it on the cheap, look for a used pair of 8-speed brifters. Shouldn't be too hard
    > to find.
    >
    > Campagnolo 8-speed spacing is the same as 7-speed, so 8-speed shifters will index perfectly with a
    > 7-speed setup.
    >
    > I don't believe you'll need to change anything else but the handlebar
    tape.
    >
    > If 7-speeds isn't enough for your winter beater, skip 8 and go to 9-speeds. That will need a new
    > rear wheel, chain & cassette.
    >
    > Sheldon "Cheaper Than You Think" Brown +--------------------------------------------+
    > | Never worry about theory as long as the | machinery does what it's supposed to do. | --Robert
    > | A. Heinlein |
    > +--------------------------------------------+ 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
     
  3. Pete Biggs

    Pete Biggs Guest

    Sheldon Brown wrote:

    > Campagnolo 8-speed spacing is the same as 7-speed

    I've found a small inconsistency between the Campagnolo 8-speed spacing info on
    www.sheldonbrown.com/k7.html#spacing and www.campagnolo.com/pdf/ruote98.pdf (page 18):

    Sheldon, you say: sprocket = 1.8, spacer = 3.2mm, Campag say 1.85 and 3.2, so c-c would be
    5.05 not 5.0.

    > so 8-speed shifters will index perfectly with a 7-speed setup.

    I'm sure it will index fine (as any error will be so small), but it would be nice to have the
    correct info on your website - if you can change it (if it is wrong?).

    Thanks again for a great website. I will email a copy of this post if no reply here.

    ~PB
     
  4. Pete Biggs

    Pete Biggs Guest

    Pete Biggs wrote:

    > Sheldon, you say: sprocket = 1.8, spacer = 3.2mm, Campag say 1.85 and
    > 3.2, so c-c would be 5.05 not 5.0.

    Correction: you say spacer = 3.1.

    ~PB
     
  5. Tom-<< This is probably an oft asked question, but I'm looking at upgrading my old 'winter' bike's
    7sp set to something a bit more modern, mainly so I can throw some Ergo levers on there. >><BR><BR>

    << At the moment, I have a fairly generic (in that I can't remember what it is) 7speed block on the
    back, with a Mirage '97? rear mech. I understand the rear mech will have to (obviously) be upgraded
    too >><BR><BR>

    Nope, not if it not worn out..It will work fine with ERGO...any of them.

    << I understand I also need 130mm between rear dropouts to fit these modern hubs in, some pointers
    on where to measure ths from would be much appreciated. The frame is about 6-7 years old, Reynolds
    CR(o)MO tubing. >><BR><BR>

    If 6-7 years old, made about 1995 or so, it should be 130mm..if not, easy to 'cold set'-

    Get a Campagnolo 9/10s rear hub, build a wheel, get some ERGOs, match the cogset to the ERGO
    speeds(9s or 10s) get a chain, go ride.

    Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
    (303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene"
     
  6. I asserted:

    >>Campagnolo 8-speed spacing is the same as 7-speed so 8-speed shifters will index perfectly with a
    >>7-speed setup.

    Pete Biggs demurred:
    >
    > I've found a small inconsistency between the Campagnolo 8-speed spacing info on
    > www.sheldonbrown.com/k7.html#spacing and www.campagnolo.com/pdf/ruote98.pdf (page 18):
    >
    > Sheldon, you say: sprocket = 1.8, spacer = 3.2mm, Campag say 1.85 and 3.2, so c-c would be 5.05
    > not 5.0.

    Then:

    > Correction: you say spacer = 3.1.

    Actually, I say 1.9 for the sprocket, not 1.8.

    I got these numbers from the Quality Bicycle Products catalogue.

    I have here a brand new Campagnolo Ultra Drive 8-speed cassette and a decent dial caliper.

    I actually measure the sprockets in the range of 1.86-1.88, and the spacers a bit thicker than 3.1.
    Given the low precision of the parts involved, rounding to the nearest tenth seems reasonable to me.

    Sheldon "The Plastic Spacers Will Vary Depending On How Tight The Lockring Gets" Brown
    +--------------------------------------------------------+
    | As far as the laws of mathematics refer to reality, | they are not certain; and as far as they
    | are certain, | they do not refer to reality. --Albert Einstein |
    +--------------------------------------------------------+ 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
     
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