Discussion in 'Cycling Equipment' started by Gary Jacobson, Jun 11, 2003.

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  1. Found on IBOB, and I thought to share it with this R.B.T. From:


    In the old days of friction shifters, it was all so simple. But now that most of us have ‘dumbed
    down’ and use indexed gears, manufacturers and retailers have us brainwashed into believing that
    only a matched system, from lever through rear mech to cassette and hub, will give a workable setup.
    The other day I mail-ordered some Campagnolo Ergo 9-speed levers, and a Shimano 8/9-speed freehub -
    the silence that greeted this combination was deafening, to be replaced only by tooth-sucking noises
    down the telephone. Well, a lot depends on how fussy you are, but if there’s a bottom line to this
    article, it’s ‘just do it’. Measurements in these gear systems are made to the nearest 1/100th of a
    millimeter (see tables below) which makes them sound like precision instruments - but these are
    derailleur gears we’re talking about for heavens sake - you know, clunk, clatter and grind? In fact
    modern derailleurs have about 1mm of ’slop’ designed in, to allow for a degree of maladjustment.
    This table shows the spacing of various common types of gear cluster, obviously the centre-to-centre
    spacing is the important column. It’s based on a similar table at Sheldon Brown’s website, www.
    sheldonbrown. com/k7. html#spacing

    Sprocket Space C-to-C thickness Sprocket thickness Spacer Sprocket Marchisio Spacer Old 5, 6
    ~5.35 ~1.85 ~3.50 Old Compact/Ultra 6 5.00 1.85 3.15 Shimano HG7~speed 5.00 1.85 3.15 ~1.5 ~3.5
    blue Shimano IG7~speed 5.00 2.35 2.65 ~1.5 ~3.5 blue Campagnolo 8~speed 5.00 1.90 3.10 ~1.5 ~3.5
    blue Sachs 7sp & 1997 8sp 5.00 1.80 3.20 ~1.5 ~3.5 blue Sachs 1998+ 8~speed 4.80 1.80 3.00 ~1.5
    ~3.3 red Shimano 8~speed 4.80 1.80 3.00 ~1.5 ~3.3 red Campagnolo 9~speed 4.55 1.75 2.80 ~1.5
    ~3.05 black Shimano 9~speed 4.34 1.78 2.56 ~1.5 ~2.9 grey Campagnolo 10~speed 4.12 1.70 2.42 ~1.5
    ~2.7 yellow

    (All measurements in mm)

    The RH column shows what Marchisio kit would be needed to replicate the spacings on the left. To me,
    with a preference for Campagnolo’s Ergo levers but having a large stock of Shimano rear hubs, some
    of the options available via Marchisio are very attractive. For example, a ’Campag’ 9sp cassette
    that fits on a Shimano 8/9 hub, with an 11t top sprocket, that can still take a good old cheap and
    cheerful Sedis chain (chain width is mainly governed by spacer thickness). Very nice. But expensive,
    and you do lose some of the sweet changing that you get with Shimano’s clever ‘pre-worn’ cassettes.

    So this article is mainly about matching superior Campag front-ends with superior Shimano
    back-ends ...

    As you probably know, it is the lever which does most of the magic in an indexed system such as Ergo
    or STI. The rear mech is fundamentally unchanged in design ever since certain patents expired
    several years ago and Campagnolo and Shimano were able to copy the superior geometry pioneered by
    Suntour, who promptly went under. The rear mech doesn’t care what is pulling its string, or who has
    painted ’8-speed’, ’9-speed’ or ’10-speed’ on its body. All modern Campag mechs shift the same
    amount, and (nearly) all modern Shimano mechs shift the same amount – for a given cable pull,
    Shimano mechs shift a bit further than Campag and this is why the two systems are incompatible.
    (Some Dura-Ace kit is different again, and should be seen as an exception.) Here is the ’shift’ with
    various Ergo/STI lever/rear mech combinations –

    Lever: Mech: Shift: Campag 8 Campag 5.00mm Shimano 8 Shimano 4.80mm Campag 9 Campag 4.55mm Campag
    9 Shimano ~5.05mm Shimano 9 Shimano 4.35mm Campag 10 Campag ~4.12mm Campag 10 Shimano ~4.60mm(This
    is a guess)

    So for example, apart from the obvious ’matched’ combinations, a Campag 8 lever and mech is a
    perfect match for any old 7-speed block, because they all share a 5mm spacing. Campag 8sp lever/mech
    onto Shimano 7sp cassette is a setup I’ve been using for years. How much tolerance is allowable,
    this must depend on the spacing of the cluster, the width of the chain, the type of rear mech (long
    or short arm) and to a lesser extent the type of sprockets in use. Even, how careful you are when
    clamping the cable at the rear mech - if its not seated absolutely correctly then this will affect
    the amount of ’shift’. Certainly a discrepancy of 5% (up to 0.2mm) does not seem to me to present
    any real problem, especially if it is the ’shift’ which is greater than the spacing. I’ve built an
    ’overchanging’ combination of this sort and its just fine, with snappy changes right across the
    block. That’s Campag 9sp lever, Shimano mech, Shimano 8sp cassette - not even difficult to set up.
    If the ’shift’ is less than the spacing, this is an ’under changing’ combination and I’d guess that
    3% (0.1mm-ish) would be a safer figure. However, it’s well-documented that Shimano 9sp lever/mech
    onto Campag 9sp block works OK - even though this is under changing by 5%, which I would expect to
    give sluggish changes. The reverse (Campag 9sp lever/mech onto Shimano 9-block) is also known to
    work and I would expect this 5% over change to be a much better combination, in fact possibly even
    preferable to a matched Campag 9sp system. Here is that table again, with two additional columns -
    these Lever/Mech combinations should be able to handle any gear block (see table 1) whose spacing
    falls between the final two columns –

    Lever: Mech: Shift +3% -5% Block: Campag 8 Campag 5.00 5.15 4.75 eg any 7sp or 8sp Shimano 8 Shimano
    4.80 4.94 4.56 Campag 9 Campag 4.55 4.69 4.32 eg Shimano 9sp Campag 9 Shimano ~5.05 5.20 4.80 eg any
    7sp or 8sp Shimano 9 Shimano 4.34 4.47 4.12 Campag 10 Campag ~4.12 4.24 3.92 Campag 10 Shimano ~4.60
    4.74 4.37 (still guessing, probably any 9sp)

    The combination of Campag 9sp lever with Shimano rear mech will handle any 7sp or 8sp back end -
    this makes it very useful if you need to fit new levers to a bike but you have a lot of old wheels
    lying around.

    Here’s how to set up the Campag 9/Shimano/Shimano 8 combination – naming the cogs 1 (big) to 8
    (small) - go for a sluggish change from 7 to 6. Tweak that inwards by the proverbial gnat’s whisker
    so that it’s no longer sluggish. Changing down onto bigger cogs, the change now just gets better the
    further you go. Use the limit screw to stop it going ’over’ on the smallest cog. Likewise on the
    biggest, but err on the generous side here, or you will generate a lot of unwanted cable tension in
    bottom gear. The largest error overall is about 1mm, on cog 2, which runs just about OK.

    Francis Cooke

  2. Jp

    Jp Guest

    "Gary Jacobson" <[email protected]> wrote in message
    news:<[email protected]>...
    > Found on IBOB, and I thought to share it with this R.B.T. From:
    > http://homepage.ntlworld.com/icknield_roadclub/docs/newslett.htm#MIX%92N%20M
    > The combination of Campag 9sp lever with Shimano rear mech will handle any 7sp or 8sp back end -
    > this makes it very useful if you need to fit new levers to a bike but you have a lot of old wheels
    > lying around.
    > Francis Cooke

    This would seem to say that I could use Mirage Ergo levers with my old (but not very used) Sante RD
    and old (but not very used) 7 speed regina freewheels? I guess I would have a couple of
    nonfunctional clicks. My objective is to get handlebar click shifting without a big initial
    investment, or maybe no other investment, since I'm pretty satisfied with the gear range and spacing
    I get with my current setup.

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