Granny gear for Campy Veloce

Discussion in 'Cycling Equipment' started by Robert Strickla, Apr 19, 2003.

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  1. I've finally gotten around to picking up a used Campy Veloce crankset. The smallest chainring is a
    30 and the largest a 52 but I'd like to swap them for something at least a little smaller. The
    question is how low can I go. The Veloce FD info says it's rated for a 22 tooth difference between
    smallest and biggest ring. That would suggest a 28 small ring and a 50 big ring is my best bet. Can
    I get away with a granny gear that's even smaller and still have acceptable shifting? How about a 24
    tooth small ring? Thanks in advance.

    Rob Strickland
     
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  2. A Muzi

    A Muzi Guest

    "Robert Strickland" <[email protected]> wrote in message
    news:[email protected]...
    > I've finally gotten around to picking up a used Campy Veloce crankset. The smallest chainring is a
    > 30 and the largest a 52 but I'd like to swap them for something at least a little smaller. The
    > question is how low can I go. The Veloce FD info says it's rated for a 22 tooth difference between
    > smallest and biggest ring. That would suggest a 28 small ring and a 50 big ring is my best bet.
    > Can I get away with a granny gear that's even smaller and still have acceptable shifting? How
    > about a 24 tooth small ring?

    Maybe maybe not. I would get the gearing you require ( 74mm rings are both ubiquitous and cheap) and
    try it. You may well find the chain drags the bottom of the cage when you shift to the 24-12. From
    your description it may also drag on the next few cogs too. That's something many riders just live
    with ( remembering to find a similar gear on the middle ring instead). If you aren't happy with
    that, you might choose another front changer later. At least Campagnolo still bolts the entretoise,
    so you needn't ditz with chain rivets to just swap the front changer.

    --
    Andrew Muzi http://www.yellowjersey.org Open every day since 1 April 1971
     
  3. Pete Biggs

    Pete Biggs Guest

    Robert Strickland wrote:
    > I've finally gotten around to picking up a used Campy Veloce crankset. The smallest chainring is a
    > 30 and the largest a 52 but I'd like to swap them for something at least a little smaller. The
    > question is how low can I go. The Veloce FD info says it's rated for a 22 tooth difference between
    > smallest and biggest ring. That would suggest a 28 small ring and a 50 big ring is my best bet.
    > Can I get away with a granny gear that's even smaller and still have acceptable shifting? How
    > about a 24 tooth small ring? Thanks in advance.

    24 is the smallest that will fit the cranks, and I sucessfully got Veloce 24-39-52 working on two
    bikes using a Centaur braze-on triple front derailleur and Racing T rear on one, and old Shimano
    equipment on the other.

    However, on a previous bike, with an older Mirage T front der. and Avanti triple rear, I struggled
    even to get 30-40-53 working well. Using a smaller big ring will help as front der. can be lower.

    The jump between middle and 24t granny is a bit crazy though: like changing down a load of gears at
    once, and chainline and capacity will greatly restrict the number of rear sprockets that can be used
    with it, leaving a gap in range of useable gears. So, unless you absolutely need the lowest gears
    possible, I suggest first trying 28, 27 or 26. TA make suitable 74mm rings in these sizes.

    39 is the smallest possible size for the middle, by the way.

    ~PB
     
  4. Pete Biggs

    Pete Biggs Guest

    Pete Biggs wrote:
    > 24 is the smallest that will fit the cranks, and I sucessfully got Veloce 24-39-52 working on two
    > bikes using a Centaur braze-on triple front derailleur and Racing T rear on one, and old Shimano
    > equipment on the other.

    Correction: One bike was with 24-39-52, other with 24-40-52 and 24-42-52. (This may be reasuring if
    you have the standard 42t middle).

    ...Doesn't half look weird, especially as my granny is black [no jokes please!]. Looks like a normal
    double crankset with a stealth miniture inner ring that can hardly be seen.

    ~PB
     
  5. On Sat, 19 Apr 2003 18:45:51 +0200, Robert Strickland wrote:

    > I've finally gotten around to picking up a used Campy Veloce crankset. The smallest chainring is a
    > 30 and the largest a 52 but I'd like to swap them for something at least a little smaller. The
    > question is how low can I
    go.

    I don't know the bolt circle on the granny, but the middle one can only go down to 39. Look at the
    current granny and measure from the ridge beneath the teeth to the top of the bolts used to hold it
    on. Muptiply that number (in inches) by 2 pi, well, 6.3 will do, and go down to the next whole
    number. That is the theoretical number of teeth you can knock off from the chainring you have to the
    smallest chainring you can put on there.

    For example, if that distance is 1/2", then you get 3.14 fewer teeth; really you can theoretically
    get a chainring with 3 fewer teeth. I don't know if it is made, though.

    > The Veloce FD info says it's rated for a 22 tooth difference between smallest and biggest ring.
    > That would suggest a 28 small ring and a 50 big ring is my best bet. Can I get away with a granny
    > gear that's even smaller and still have acceptable shifting? How about a 24 tooth small ring?

    I doubt that you will be able to fit a 24, or even a 28 on the cranks. Maybe, but I doubt it.

    You can easily switch cranks to one with either a 110/74 bolt circle, or a
    94/58. These are mountain bike sizes (standard and compact) and are widely available cheap. At swap
    meets, my limit is $5 for a chainring, and I have a couple dozen (for 3 bikes).

    --

    David L. Johnson

    __o | Accept risk. Accept responsibility. Put a lawyer out of _`\(,_ | business. (_)/ (_) |
     
  6. Pete Biggs

    Pete Biggs Guest

    David L. Johnson wrote:
    > On Sat, 19 Apr 2003 18:45:51 +0200, Robert Strickland wrote:
    >> I've finally gotten around to picking up a used Campy Veloce crankset. The smallest chainring is
    >> a 30 and the largest a 52 but I'd like to swap them for something at least a little smaller. The
    >> question is how low can I go.
    >
    > I don't know the bolt circle on the granny

    74mm.

    > , but the middle one can only go down to 39.

    That's because it's 135mm.

    > Look at the current granny and measure from the ridge beneath the teeth to the top of the bolts
    > used to hold it on. Muptiply that number (in inches) by 2 pi, well, 6.3 will do, and go down to
    > the next whole number. That is the theoretical number of teeth you can knock off from the
    > chainring you have to the smallest chainring you can put on there.
    >
    > For example, if that distance is 1/2", then you get 3.14 fewer teeth; really you can theoretically
    > get a chainring with 3 fewer teeth. I don't know if it is made, though.

    That's all very interesting, probably, but the answer is 24 :)

    24t fits and works. Shimano, TA and others make the suitable 74mm 5-arm rings.

    ~PB
     
  7. You can stretch the overall capacity of a front derailleur somewhat. The worst that will happen is
    that the chain wil drag on the bottom of the cage in the smaller cogs.

    It's very unlikely you will be able to use the smalest cogs anyway, esp. if you have an 8, 9 or
    (gasp!) 10 cog hubset.

    May you have the wind at your back. And a really low gear for the hills! Chris

    Chris'Z Corner "The Website for the Common Bicyclist": http://www.geocities.com/czcorner
     
  8. "Pete Biggs" <pLime{remove_fruit}@biggs.tc> wrote in message
    news:[email protected]...
    > Pete Biggs wrote:
    > > 24 is the smallest that will fit the cranks, and I sucessfully got Veloce 24-39-52 working on
    > > two bikes using a Centaur braze-on triple front derailleur and Racing T rear on one, and old
    > > Shimano equipment on the other.
    >
    > Correction: One bike was with 24-39-52, other with 24-40-52 and 24-42-52. (This may be reasuring
    > if you have the standard 42t middle).
    >
    > ...Doesn't half look weird, especially as my granny is black [no jokes please!]. Looks like a
    > normal double crankset with a stealth miniture inner ring that can hardly be seen.
    >
    > ~PB

    I'm going to give 50/39/24 a shot. That matches my road bike gearing but adds a nice low granny gear
    for "emergency" hills. Thanks for the info.

    Rob Strickland
     
  9. Mark Janeba

    Mark Janeba Guest

    Robert Strickland wrote:
    > I've finally gotten around to picking up a used Campy Veloce crankset. The smallest chainring is a
    > 30 and the largest a 52 but I'd like to swap them for something at least a little smaller. The
    > question is how low can I go. The Veloce FD info says it's rated for a 22 tooth difference between
    > smallest and biggest ring. That would suggest a 28 small ring and a 50 big ring is my best bet.
    > Can I get away with a granny gear that's even smaller and still have acceptable shifting? How
    > about a 24 tooth small ring? Thanks in advance.

    I've used campy with a 26T small chainring and 52T large (we are talking triple here, right?) and
    had acceptable shifting, though the upshifts off the 26T were not as smooth as with the 30T small
    ring. I intentionally avoided the smallest 4 cogs in the rear when using the small ring, so I can't
    speak to how they would work. This was to avoid chain wrap problems with the R. der.

    Setup was with a Campy Racing-T crankset, nearly identical to the Veloce, and Veloce front and rear
    derailleurs, 12-23 cogs in the rear.

    Regards,
    --
    Mark Janeba remove antispam phrase in address to reply
     
  10. On Sun, 20 Apr 2003, Robert Strickland wrote:

    > I'm going to give 50/39/24 a shot. That matches my road bike gearing but adds a nice low granny
    > gear for "emergency" hills. Thanks for the info.
    >

    Good luck--it should work. I'm currently using a TA 48/38/24 with a Daytona/Centaur front
    on my bike.

    Trent
     
  11. Eric Salathe

    Eric Salathe Guest

    "Robert Strickland" <[email protected]> wrote in message
    news:<[email protected]>...
    > I've finally gotten around to picking up a used Campy Veloce crankset. The smallest chainring is a
    > 30 and the largest a 52 but I'd like to swap them for something at least a little smaller. The
    > question is how low can I go. The Veloce FD info says it's rated for a 22 tooth difference between
    > smallest and biggest ring. That would suggest a 28 small ring and a 50 big ring is my best bet.
    > Can I get away with a granny gear that's even smaller and still have acceptable shifting? How
    > about a 24 tooth small ring? Thanks in advance.

    We use 54-42-28 rings on the tandem with 28-11 in the rear. That would be the same range as
    50-40-24. I use Campy Barcons or Ergo levers, Veloce RD, and Sachs Centera FD. The Sachs MTB front
    derailleurs had the largest capacity ever, but a Campy FD should be close enough.

    What you will need, however, is a chain watcher. There are two types, from Third Eye and from N
    Gear. Both work fine. Without one you will never get reliable shifting to the granny without dumping
    the chain. Sure it will work on the bike stand, but will fail 99% of the time on the road.

    I'd recommend 50-40-24 since Campy makes matched 50-40 rings with ramps and pins.

    Eric Salathe
     
  12. Pete Biggs

    Pete Biggs Guest

    Eric Salathe wrote:
    > What you will need, however, is a chain watcher. There are two types, from Third Eye and from N
    > Gear. Both work fine. Without one you will never get reliable shifting to the granny without
    > dumping the chain. Sure it will work on the bike stand, but will fail 99% of the time on the road.

    That's not true in my experience. The chain with my 24-40-52 without a chain watcher is only being
    dumped 1% of the time on the road. Fitting the FD _low_ is the key. Not a bad idea to get a chain
    watcher, though.

    ~PB
     
  13. Archer

    Archer Guest

    In article <[email protected]>, pLime{remove_fruit}@biggs.tc says...
    > Eric Salathe wrote:
    > > What you will need, however, is a chain watcher. There are two types, from Third Eye and from
    > > N Gear. Both work fine. Without one you will never get reliable shifting to the granny
    > > without dumping the chain. Sure it will work on the bike stand, but will fail 99% of the time
    > > on the road.
    >
    > That's not true in my experience. The chain with my 24-40-52 without a chain watcher is only being
    > dumped 1% of the time on the road. Fitting the FD _low_ is the key. Not a bad idea to get a chain
    > watcher, though.

    What is a chain watcher? I can figure out that it's something to keep the chain on the ring, but how
    does it mount, work, etc? Any pictures you can point to?

    --
    David Kerber An optimist says "Good morning, Lord." While a pessimist says "Good Lord,
    it's morning".

    Remove the ns_ from the address before e-mailing.
     
  14. Pete Biggs

    Pete Biggs Guest

    Pete Biggs wrote:
    > ...........The chain with my 24-40-52 without a chain watcher is only being dumped 1% of the time
    > on the road.

    ps. And I'm sure that's only because I'm having teething problems. Should be able to get failure
    rate down to 0.068521% with a bit more adjustment :)

    ~PB
     
  15. Pete Biggs

    Pete Biggs Guest

  16. Eric Salathe

    Eric Salathe Guest

    "Pete Biggs" <pLime{remove_fruit}@biggs.tc> wrote in message
    news:<[email protected]>...
    > Eric Salathe wrote:
    > > What you will need, however, is a chain watcher. There are two types, from Third Eye and from
    > > N Gear. Both work fine. Without one you will never get reliable shifting to the granny
    > > without dumping the chain. Sure it will work on the bike stand, but will fail 99% of the time
    > > on the road.
    >
    > That's not true in my experience. The chain with my 24-40-52 without a chain watcher is only being
    > dumped 1% of the time on the road. Fitting the FD _low_ is the key. Not a bad idea to get a chain
    > watcher, though.

    A bit of an overstatement on my part. However, I've been on enough tandem rides where every time the
    group hits a steep hill, I'm the only one snapping the chain down to the granny exactly when I want
    and the only one with a chain watcher. 1/3 dump the chain, 1/3 grunt up the hill in a bigger gear
    than they'd like, and 1/3 shift too early to avoid the mess. Tandems are particularly challanging
    since you cannot synchronize removing pedalling force to shift in that instant before momentum is
    lost and you bog down.

    Still, it is always a tight compromise between avoiding dumping the chain and missing your shift.
    Take a look at the FD. The outer plate is designed to shove the chain off a 52T chainring but not so
    far as to overshoot a 42T ring. Now you're using that same metal plate to shove a chain off a 42T
    ring and not miss a 24T ring. No matter what linkages, bumps, and kinks they put into the plates,
    front derailleurs simply are not optimally designed to shift a triple.

    Eric Salathe
     
  17. Whitfit

    Whitfit Guest

    I have a 52-42-24 setup (Shimano) with an n-gear jump stop, which is a pretty good chain watching
    device. I am using an old Sachs front changer (Bar-cons) which I ground to match outer ring shape.
    Results- Almost perfect. The chain drags on the smaller cogs, but when I need the granny with a
    load, I usually need the larger cogs anyway. I wouldn't mind having a lower range in front (Like
    38-48 or something) but I have tall gears and a good range of gears in the middle right now with my
    13-30 cassette.

    Whitfit.
     
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