Question about White Industries MTB hubs

Discussion in 'Cycling Equipment' started by Keith Beck, Jul 27, 2004.

  1. Chalo wrote in message <[email protected]>...
    Perhaps the lightest cartridge hubs used titanium axles.
    What was their weight, and how do they compare to Campag Record with
    titanium axles(c1980)? Compare like with like here. Exlude skewers off
    all.

    >So to you, a mallet is a "special tool"? My oldest wheel has its
    >original bearing cartridges in it. At about 35,000 miles it is
    >beginning to exhibit wear and a bit of roughness in the bearing
    >surfaces, but no more so than the average _brand new_ cup & cone hub.
    >

    That is admirable that you still have a serviceable unit using original
    cartridge bearings after 35,000miles. Are they sealed cartridge?
    What is the exact type of bearing , dimensions and fit?
    What is the make/model of hub, cost and when?
    So how do you know a mallet is all it would take to exchange these bearings?
    Has it seen water?
    Actual service life is important, but how well does it roll compared to an
    equivalently priced cup&cone model of the same period.
    That bit of roughness shows the bearing surface has failed.

    OK for some people tub's may be inappropriate due to the lack of
    availability of wide off the peg models. At a guess I think you would need
    35mm section in a tub a little more with wired-on.


    Motorcycle - Nice big motor with plenty of reserve power, large wheel
    bearings large stiff rear fork/front fork thick solid axles.
    Power of motorcycle typically160 000watts
    Power of cyclist 120watts
    priority of cyclist - develop a little bit of power, make it go, make it
    stop, make it turn, pare weight
    priority of motorcyclist - Develop plenty of power, make it go, make it
    stop, make it turn, protect components

    >
    >There are such bearing cartridges as you describe, but they are not
    >generally used in bicycles. The usual kind are "double sealed deep
    >groove radial contact" bearings, with two contact points per ball.


    This type of bearing, has a high degree of osculation and much sliding
    takes place, so is intolerant to contaminent and must be highly protected
    against ingress so upping the cost of the hub. The slow and stop conditions
    of a bicycle make this the quickest wearing choice of rolling bearing .
    Without renewal of lubricant alongside removal of wear debris, this will
    make it the first to fail through fatigue. It is almost not a rolling
    bearing.
    What milage do the bearing surfaces of this type typacally fail at? And at
    what size are they?
    I feel it woul be more apprpriate to use taper rollers with an oil feed.
    This requires adjustment but I don't think is available in the small sizes
    required for hubs and pedals antway.

    What you infer is that for the inexpert or forgetful mechanic, sealed
    cartridges are more suitable. I say, if it drips oil, a cup and cone
    bearing will outlive you.
    I think that your assessment of c&c bearings being poor is based on
    experience with incorrectly lubricated units. Ideally the balls should roll
    in an oil bath.
    TJ
     


  2. [email protected] wrote in message ...
    >I'm not quite clear whether you mean that your hill includes
    >the 1 in 3 hairpin, or 33% grade, or if you mean that the
    >hairpin is in the other hill, but either way it seems
    >unlikely that anyone does 60 mph through a hairpin.
    >

    The old road contains the hairpin. The new road is declared a trunk road.
    >What would you say the grade is on the section where you
    >exceed 60 mph?

    10% maybe less, have to check by map.
    >
    >Is this the mountain bike trail that I see on the internet
    >when I google for bwlch, or is it a road? That is, are we
    >talking about a ski-resort dirt-descent specialty-downhill
    >or a paved road?

    Single carriageway trunk road. Scares the shit outa some.
    Motorcyclists coming towards you at 100mph+ dont always return to their
    nearside, I guess so they can see around the bend which of course I want to
    cut. The lead rider must keep their head up for this reason.
    It takes three or four riders riding close to get past 100kmh
    TJ Now stop it!
     
  3. On Tue, 3 Aug 2004 02:54:19 +0100, "Trevor Jeffrey"
    <[email protected]> wrote:

    >
    >[email protected] wrote in message ...
    >>I'm not quite clear whether you mean that your hill includes
    >>the 1 in 3 hairpin, or 33% grade, or if you mean that the
    >>hairpin is in the other hill, but either way it seems
    >>unlikely that anyone does 60 mph through a hairpin.
    >>

    >The old road contains the hairpin. The new road is declared a trunk road.
    >>What would you say the grade is on the section where you
    >>exceed 60 mph?

    >10% maybe less, have to check by map.
    >>
    >>Is this the mountain bike trail that I see on the internet
    >>when I google for bwlch, or is it a road? That is, are we
    >>talking about a ski-resort dirt-descent specialty-downhill
    >>or a paved road?

    >Single carriageway trunk road. Scares the shit outa some.
    >Motorcyclists coming towards you at 100mph+ dont always return to their
    >nearside, I guess so they can see around the bend which of course I want to
    >cut. The lead rider must keep their head up for this reason.
    >It takes three or four riders riding close to get past 100kmh
    >TJ Now stop it!
    >


    Dear Trevor,

    If you reveal marvels like this, you can hardly expect
    people to stop asking for explanations. (I will, however,
    skip the raised eyebrows about motorcycles routinely
    climbing such grades at over 100 mph.)

    For a typical bicycle rider's weight and profile, a long
    stretch of extremelly rare 15.4% grade is required to reach
    60 mph.

    Heavier riders with improved tucks can do better. Chalo
    Colina, for example, may be able to reach 60 mph on a mere
    6.6% slope, since he enjoys considerably increased force
    (over 400 pounds with bicycle) without a corresponding
    increase in wind drag.

    Pedalling, of course, is unlikely to be of any value. Over
    157 rpm is required to pedal 60 mph on a 700c 53x11 and
    would involve losing more to increased wind drag than could
    be made up.

    Perhaps you could check the details again with the other two
    or three riders involved and persuade them to favor us with
    a post or two about the maximum recorded on their
    speedometers?

    Meanwhile, you might enjoy plugging a few figures into this
    speed calculator:

    http://www.analyticcycling.com/ForcesSpeed_Page.html

    Set the power to 0 watts and the slope to -0.154 and you'll
    produce a speed of about 60 mph for a 75kg rider and
    bicycle. Plug in Chalo's 182kg and the result converts to
    93.5 mph.

    I never trust my conversions, so I like to check them here:

    http://members.aol.com/javawizard/speed.html

    You can reduce various factors to increase speed, but you'll
    have to keep them believable. A 10% slope with the defaults
    produces only 48 mph. Increasing this 25% would be
    impressive.

    You may also have some explaining to do in order to convince
    people that a peloton coasts downhill faster than a single
    coasting rider. As I understand it, the lead rider works
    like a dog and those who follow enjoy the reduced wind drag
    available just behind him.

    There are regular discussions here about whether the leader
    benefits slightly from someone filling in his slipstream,
    but I can't recall anyone claiming an improvement of more
    than a mile per hour.

    People do maintain sites reporting impressive climbs and
    descents for bicyles, so you might want to look into getting
    your local route listed if it turns out to have a
    significant stretch of 10% grade.

    Here are two links to places that list notable climbs:

    http://www.ulb.ac.be/di/ssd/ldoyen/e/v.html

    http://www.cyclos-cyclotes.org/altigraph.html

    Cheers,

    Carl Fogel
     
  4. Chalo

    Chalo Guest

    "Trevor Jeffrey" <[email protected]> wrote:
    >
    > Perhaps the lightest cartridge hubs used titanium axles.
    > What was their weight, and how do they compare to Campag Record with
    > titanium axles(c1980)? Compare like with like here. Exlude skewers off
    > all.


    Consult Damon Rinard's component weights:
    http://www.geocities.com/kwanseng/weight.html#fronthubs

    These are out of date, but informative. Note that the hubs are
    arranged in order of ascending weight, that the measured front hubs
    begin at 64 grams, and that the first cup & cone hub on the list
    weighs 115g. The lightest cup & cone hub on the list that I know to
    have a steel axle weighs 128g.

    I am certain that all of the very lightest hubs use aluminum axles,
    made feasible by large diameters and smooth outer surfaces.

    Other verified weight lists show examples down to 52g. There are more
    data here, but nothing by Campagnolo on this list:
    http://weightweenies.starbike.com/listings/components.php?type=hubs

    > That is admirable that you still have a serviceable unit using original
    > cartridge bearings after 35,000miles. Are they sealed cartridge?
    > What is the exact type of bearing , dimensions and fit?
    > What is the make/model of hub, cost and when?


    The wheel in question uses a front Specialized hub (made by Suzue
    IIRC) that has a traditional-looking shell, adjusters and locknuts.
    Under a set of cosmetic dustcaps, it hides 6000-2RS double sealed
    made-in-Japan cartridges, which measure 10x26x8mm. I bought it in
    1989; I don't remember how much it cost except that it was a little
    cheaper than Deore XT at the time.

    > So how do you know a mallet is all it would take to exchange these bearings?


    This particular hub requires cone wrenches to remove the locknuts and
    adjusters from one side, after which a tap to the axle end drives out
    the other side.

    > Has it seen water?


    Yes. It lived out its days on a daily rider in Austin, TX, where rain
    arrives infrequently but usually in God's Own Buckets. So the hub
    didn't get wet often, but it got plenty wet.

    > That bit of roughness shows the bearing surface has failed.


    Yes, those bearings are done. They still don't have much more end
    play than they ever did, but their former glassy smoothness is gone.
    I don't use that wheel anymore so I haven't bothered to replace the
    cartridges.

    > I feel it woul be more apprpriate to use taper rollers with an oil feed.
    > This requires adjustment but I don't think is available in the small sizes
    > required for hubs and pedals antway.


    Well, yes they are, but at a cost that would make components with such
    bearings prohibitively expensive.

    > I say, if it drips oil, a cup and cone bearing will outlive you.

    ....
    > I think that your assessment of c&c bearings being poor is based on
    > experience with incorrectly lubricated units. Ideally the balls should
    > roll in an oil bath.


    I have to admit that in my years of bike wrenching and bike building,
    I have never knowingly met a cyclist who packed hub bearings in
    anything other than some kind of grease. I have heard the hub center
    drillings on Nuovo Record hubs referred to as "oil holes" but have
    never seen them used in that way.

    It sounds like a good way to keep a bearing clean and a bike filthy.
    I suppose the thing gets "washed" often enough in Old Blighty.

    Chalo Colina
     
  5. Gary Young

    Gary Young Guest

    [email protected] (Chalo) wrote in message news:<[email protected]>...
    > "Trevor Jeffrey" <[email protected]> wrote:
    >
    > > You should have used something better than this. Correctly designed
    > > cartridge hubs have a weight penalty to bear due to the requirement of a
    > > stiffer axle and hubshell than cup &cone.

    >
    > Tell me then why _all_ of the lightest hubs ever made available have
    > used cartridge bearings (e.g. Tune, TNT, Hershey, etc.)

    <snip>

    Are there any cartridge bearing hubs currently in production that
    don't cost an arm and a leg? I know you recommend the JuJu hub, but it
    seems to be available only in a 32-hole version, not 36.
     
  6. Dave Lehnen

    Dave Lehnen Guest

    [email protected] wrote:
    <snip>
    > Dear Trevor,
    >
    > If you reveal marvels like this, you can hardly expect
    > people to stop asking for explanations. (I will, however,
    > skip the raised eyebrows about motorcycles routinely
    > climbing such grades at over 100 mph.)
    >

    < snip on-topic information>
    >
    > Cheers,
    >
    > Carl Fogel


    Oh, go ahead and raise your eyebrows. Many modern sport bikes
    have the power-to-weigh to climb very steep grades at very
    high speeds.

    For example, a current open-class bike would weigh less than
    450 lb, full of gas, oil, etc, and would have far over 100
    rear-wheel horsepower when in the powerband. A rider in full
    racer-wannabe gear might be another 200 lb.

    Even if the rider isn't tucked at all, much less than 40 hp
    is required to overcome aerodynamic drag and rolling resistance
    at 100 mph. With 650 lb total weight, climbing a 33% grade at
    100 mph takes an additional 55 hp. Even at this extreme slope,
    high speeds are possible. With only a 10% grade, it takes just
    over 17 hp to overcome gravity at 100 mph.

    Motorcyclists' uphill speeds are more limited by corners, sanity
    or lack therof, and fear of legal consequences than by grade.

    Dave Lehnen
     
  7. Dave Lehnen

    Dave Lehnen Guest

    [email protected] wrote:
    <snip>
    > Dear Trevor,
    >
    > If you reveal marvels like this, you can hardly expect
    > people to stop asking for explanations. (I will, however,
    > skip the raised eyebrows about motorcycles routinely
    > climbing such grades at over 100 mph.)
    >

    < snip on-topic information>
    >
    > Cheers,
    >
    > Carl Fogel


    Oh, go ahead and raise your eyebrows. Many modern sport bikes
    have the power-to-weigh to climb very steep grades at very
    high speeds.

    For example, a current open-class bike would weigh less than
    450 lb, full of gas, oil, etc, and would have far over 100
    rear-wheel horsepower when in the powerband. A rider in full
    racer-wannabe gear might be another 200 lb.

    Even if the rider isn't tucked at all, much less than 40 hp
    is required to overcome aerodynamic drag and rolling resistance
    at 100 mph. With 650 lb total weight, climbing a 33% grade at
    100 mph takes an additional 55 hp. Even at this extreme slope,
    high speeds are possible. With only a 10% grade, it takes just
    over 17 hp to overcome gravity at 100 mph.

    Motorcyclists' uphill speeds are more limited by corners, sanity
    or lack therof, and fear of legal consequences than by grade.

    Dave Lehnen
     
  8. On Tue, 03 Aug 2004 18:51:46 GMT, Dave Lehnen
    <dclehnen[email protected]> wrote:

    >[email protected] wrote:
    ><snip>
    >> Dear Trevor,
    >>
    >> If you reveal marvels like this, you can hardly expect
    >> people to stop asking for explanations. (I will, however,
    >> skip the raised eyebrows about motorcycles routinely
    >> climbing such grades at over 100 mph.)
    >>

    >< snip on-topic information>
    > >
    >> Cheers,
    >>
    >> Carl Fogel

    >
    >Oh, go ahead and raise your eyebrows. Many modern sport bikes
    >have the power-to-weigh to climb very steep grades at very
    >high speeds.
    >
    >For example, a current open-class bike would weigh less than
    >450 lb, full of gas, oil, etc, and would have far over 100
    >rear-wheel horsepower when in the powerband. A rider in full
    >racer-wannabe gear might be another 200 lb.
    >
    >Even if the rider isn't tucked at all, much less than 40 hp
    >is required to overcome aerodynamic drag and rolling resistance
    >at 100 mph. With 650 lb total weight, climbing a 33% grade at
    >100 mph takes an additional 55 hp. Even at this extreme slope,
    >high speeds are possible. With only a 10% grade, it takes just
    >over 17 hp to overcome gravity at 100 mph.
    >
    >Motorcyclists' uphill speeds are more limited by corners, sanity
    >or lack therof, and fear of legal consequences than by grade.
    >
    >Dave Lehnen


    Dear Dave,

    True, modern motorcycles can exceed 100 mph uphill.

    My eyebrows were lifting at the notion that this is a common
    enough occurrence on an alleged 10% grade in Wales that
    bicyclists allegedly descending at over 60 mph must keep a
    wary eye out for motorcycles cornering on the wrong side of
    the road at closing speeds exceeding 160 mph.

    Perhaps I should have made my skepticism concerning the
    original poster's ability to judge speeds clearer?

    The original poster could be right about exceeding 60 mph on
    his descent--an impressive tailwind, a much steeper grade
    than he thinks, drafting trucks, or an unusually heavy build
    might let him roll a mile a minute downhill.

    He could also be right about motorcycles zooming up toward
    him on the wrong side of corners at over 100 mph so often
    that he has to keep an eye out for them.

    But poor judgement of speed is at least as likely an
    explanation. Few of us have much demonstrable skill at
    judging our own speed at such high rates, much less the
    speed of oncoming traffic. And generally we claim higher
    than actual speeds (until the police pull us over).

    Even at bicycling speeds, snap judgements of oncoming speeds
    can be ludicrous. A defense witness once accused me of doing
    well over 30 mph on a bicycle trail. I was tempted to let
    the accusation stand in exchange for a copy of the court
    record to hang on my wall to impress Lance, but honesty
    compelled me to point out that my best efforts produce only
    19 mph on the speedometer on that gentle uphill.

    Carl Fogel
     
  9. The small group decent was required as crank revs of est. 180rpm where
    attained. I think this may have been using 52x12 on 27" wheel. The bicycle
    descent speed recordings where done using cycle computers, and as we could
    overhaul cars I do not disbelieve the max speed recordings. Personally I
    was able to attain pedal revs in excess of 200rpm on the road for short
    periods. This was acheived by daily training for five weeks of round pedal
    action using light gears with acceleration bursts upwards of 10 seconds.
    All training was kept easy. The use of a cadence meter useful as I would
    push a bit harder at each burst through a ride.
    TJ
     
  10. Chalo

    Chalo Guest

    [email protected] (Gary Young) wrote:
    >
    > Are there any cartridge bearing hubs currently in production that
    > don't cost an arm and a leg? I know you recommend the JuJu hub, but it
    > seems to be available only in a 32-hole version, not 36.


    SunRace make sealed bearing hubs besides the JuJu in other drillings.
    I use their high flange 36 hole and mid flange 48 hole BMX hubsets on
    other bikes.

    Formula, Quando, DiaTech, Bulletproof, and World Class are other
    brands that produce budget-priced sealed bearing hubs. Of these I
    know for sure that Formula and DiaTech offer cartridge bearing
    cassette hubs, even in 48 hole drilling. Specialized sealed bearing
    hubs tend to be inexpensive and nicely made. Like all OEM-market
    parts, all those I have named will be available only intermittently in
    the retail market.

    Chalo Colina
     
  11. On Tue, 3 Aug 2004 23:29:41 +0100, "Trevor Jeffrey"
    <[email protected]> wrote:

    > The small group decent was required as crank revs of est. 180rpm where
    >attained. I think this may have been using 52x12 on 27" wheel. The bicycle
    >descent speed recordings where done using cycle computers, and as we could
    >overhaul cars I do not disbelieve the max speed recordings. Personally I
    >was able to attain pedal revs in excess of 200rpm on the road for short
    >periods. This was acheived by daily training for five weeks of round pedal
    >action using light gears with acceleration bursts upwards of 10 seconds.
    >All training was kept easy. The use of a cadence meter useful as I would
    >push a bit harder at each burst through a ride.
    >TJ
    >


    Dear Trevor,

    Yes, 180-200 rpm on 27 inch tires with a 52x12 produces
    62-70 mph for tires of 2136 to 2155 mm.

    But here's a typical comment on how useful pedalling is at
    60 mph and 180-200 rpm:

    http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&[email protected]

    or

    http://tinyurl.com/5znt5

    That is, can you pedal a freely suspended rear wheel up to
    that speed and cadence?Jobst Brandt suggested this as a test
    years ago, but I haven't found anyone addressing it.

    Maybe you're the one to break new ground here?

    Carl Fogel
     
  12. Gary Young

    Gary Young Guest

    [email protected] (Chalo) wrote in message news:<[email protected]>...
    > [email protected] (Gary Young) wrote:
    > >
    > > Are there any cartridge bearing hubs currently in production that
    > > don't cost an arm and a leg? I know you recommend the JuJu hub, but it
    > > seems to be available only in a 32-hole version, not 36.

    >
    > SunRace make sealed bearing hubs besides the JuJu in other drillings.
    > I use their high flange 36 hole and mid flange 48 hole BMX hubsets on
    > other bikes.
    >
    > Formula, Quando, DiaTech, Bulletproof, and World Class are other
    > brands that produce budget-priced sealed bearing hubs. Of these I
    > know for sure that Formula and DiaTech offer cartridge bearing
    > cassette hubs, even in 48 hole drilling. Specialized sealed bearing
    > hubs tend to be inexpensive and nicely made. Like all OEM-market
    > parts, all those I have named will be available only intermittently in
    > the retail market.
    >
    > Chalo Colina



    One thing that's made me stick with Shimano hubs is the worry that the
    cassette freehub body might go bad. Do these cartridge hubs use the
    same type of body as Shimano hubs. If not, are replacements readily
    available?
     
  13. Chalo

    Chalo Guest

    [email protected] (Gary Young) wrote:

    > One thing that's made me stick with Shimano hubs is the worry that the
    > cassette freehub body might go bad. Do these cartridge hubs use the
    > same type of body as Shimano hubs. If not, are replacements readily
    > available?


    I don't know, and I don't know. I have only one cassette hub among
    approximately 20 bikes, and as it's relatively new, I haven't opened
    it up to see whether it uses a cartridge bearing cassette.

    Many sealed bearing cassette hubs I have seen and serviced use a
    regular Brand S clone cup & cone freehub body. This is questionable
    practice, since any axial preload necessary for proper functioning of
    the freehub also gets transferred to the cartridge bearings, which
    don't need or like it. It does resolve your issue, though.

    As to whether there is good parts support for a given cartridge
    cassette hub, the answer is maybe, probably, perhaps. I imagine that
    it varies a lot from maker to maker, with maufacturers that have an
    established or growing reputation to uphold (e.g Specialized and
    DiaTech respectively) doing a better job of it than no-name or
    OEM-only manufacturers. Anyplace you can buy a budget cartridge
    bearing hubset would be a good place to ask whether _that seller_ can
    get you spare parts.

    Chalo Colina
     
  14. [email protected] wrote in message ...
    >Yes, 180-200 rpm on 27 inch tires with a 52x12 produces
    >62-70 mph for tires of 2136 to 2155 mm.
    >
    >But here's a typical comment on how useful pedalling is at
    >60 mph and 180-200 rpm:
    >
    >http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&[email protected]

    tx.hpl.hp.com
    >
    >or
    >
    >http://tinyurl.com/5znt5
    >
    >That is, can you pedal a freely suspended rear wheel up to
    >that speed and cadence?Jobst Brandt suggested this as a test
    >years ago, but I haven't found anyone addressing it.
    >
    >Maybe you're the one to break new ground here?


    ??

    TJ
     
  15. [email protected] wrote in message ...
    >Yes, 180-200 rpm on 27 inch tires with a 52x12 produces
    >62-70 mph for tires of 2136 to 2155 mm.
    >
    >But here's a typical comment on how useful pedalling is at
    >60 mph and 180-200 rpm:
    >
    >http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&[email protected]

    tx.hpl.hp.com
    >
    >or
    >
    >http://tinyurl.com/5znt5
    >
    >That is, can you pedal a freely suspended rear wheel up to
    >that speed and cadence?Jobst Brandt suggested this as a test
    >years ago, but I haven't found anyone addressing it.
    >
    >Maybe you're the one to break new ground here?


    ??

    TJ
     
  16. Chalo <[email protected]> wrote:
    >The combination of no axial adjustment, no periodic maintenance,
    >complete replaceability, and the lowest amount of bearing drag is an
    >unbeatable advantage for sealed cartridge hub bearings IMO.


    The point was driven home to me when replacing the original '89 Suzue
    cartridge rear hub on the tandem with a cup-and-cone (why? 'cos the old
    one is freewheel, and I don't fancy carrying the tools to pull one on the
    road, and 40-spoke to boot); the cartridge hub is really enormously easier
    to work with. The front hub stays; and if I have time to shop around next
    time I need a hub, it sure as hell won't be cup and cone.
    --
    David Damerell <[email protected]> flcl?
     
  17. On Mon, 2 Aug 2004 20:56:56 +0100, "Trevor Jeffrey"
    <[email protected]> wrote:

    >
    >[email protected] wrote in message ...
    >>What hill do you descend in excess of 60 mph?

    >
    >That was not a cue to go totally off topic. The hill/mountain? is Moel
    >Eithinen sometimes called the Bwlch as opposed to the Old Bwlch or Bwlch
    >Penbarra which contains a 1in3 hairpin. It's in N. Wales.
    >TJ
    >


    Dear Trevor,

    Would this be the area?

    http://www.streetmap.co.uk/newmap.s...&mapp=newmap.srf&searchp=newsearch.srf&dn=651

    or

    http://tinyurl.com/65jax

    That is, I see a Blwch Penbarras in the upper middle
    1000-meter square, a Moel Ethinen in the center square, and
    a Blwch-y-parc in the lower two right squares, with 10-meter
    contour lines.

    Carl Fogel
     
  18. On Thu, 05 Aug 2004 15:52:45 -0600, [email protected]
    wrote:

    >On Mon, 2 Aug 2004 20:56:56 +0100, "Trevor Jeffrey"
    ><[email protected]> wrote:
    >
    >>
    >>[email protected] wrote in message ...
    >>>What hill do you descend in excess of 60 mph?

    >>
    >>That was not a cue to go totally off topic. The hill/mountain? is Moel
    >>Eithinen sometimes called the Bwlch as opposed to the Old Bwlch or Bwlch
    >>Penbarra which contains a 1in3 hairpin. It's in N. Wales.
    >>TJ
    >>

    >
    >Dear Trevor,
    >
    >Would this be the area?
    >
    >http://www.streetmap.co.uk/newmap.s...&mapp=newmap.srf&searchp=newsearch.srf&dn=651
    >
    >or
    >
    >http://tinyurl.com/65jax
    >
    >That is, I see a Blwch Penbarras in the upper middle
    >1000-meter square, a Moel Ethinen in the center square, and
    >a Blwch-y-parc in the lower two right squares, with 10-meter
    >contour lines.
    >
    >Carl Fogel


    While it's not the Bwlch near Moel Eithinen, there is a
    short Welsh grade called Bwlch-y-Groes that descends to
    Dinas-Mawddwy with an impressively steep upper 1,000 meters:

    http://www.salite.ch/groes1.htm

    The link above shows a drop from 546 meters to 464 meters
    (16.4%) in 500 meters of road, followed by a drop from 464
    to 384 meters (16.0%) in the next 500 meters of road, an
    average of 16.2% for a kilometer.

    This is followed by another kilometer at 14.2% grade from
    384 meters down to 242 meters.

    (The site's list of 54 Welsh climbs lists this one at an
    average of 12.5%, with no others averaging even 9% and no
    obvious stretches exceeding 12%.)

    Here's a map:


    http://www.streetmap.co.uk/newmap.s...&mapp=newmap.srf&searchp=newsearch.srf&dn=654

    or

    http://tinyurl.com/4qhg9

    And here's a commentary page:

    http://www.iseran.com/Atlas/bwlch_y_groes.html

    Plugging 0 watts power (no pedalling) and -0.164 slope into:

    http://www.analyticcycling.com/ForcesSpeed_Page.html

    calculates a speed of 27.54 mps (61-62 mph) for a 75kg bike
    and rider.

    For a -0.142 slope and 0 watts power, the same defaults
    yield 25.74 mps (or 57-58 mph).

    Of course, this assumes that the approach, distance, and
    curves allow the bike and rider to reach terminal velocity
    within a kilometer.

    If there's an unlisted stretch of paved road in Wales whose
    grade exceeds 10%, the folks at http://www.salite.ch would
    love to hear about it. (Click on English and a display
    appears by country, including Wales.)

    Carl Fogel
     
  19. Bill Lloyd

    Bill Lloyd Guest

    Well I guess in the UK they don't have the altitude, but I've hit 63.5
    mph in the Sierras in eastern California, descending from north lake
    Tahoe to Truckee.

    The grade isn't all that steep, either -- maybe 10%? But it's at 8500'
    give or take.


    On 2004-08-02 20:29:38 -0700, [email protected] said:

    > On Tue, 3 Aug 2004 02:54:19 +0100, "Trevor Jeffrey"
    > <[email protected]> wrote:
    >
    >>
    >> [email protected] wrote in message ...
    >>> I'm not quite clear whether you mean that your hill includes
    >>> the 1 in 3 hairpin, or 33% grade, or if you mean that the
    >>> hairpin is in the other hill, but either way it seems
    >>> unlikely that anyone does 60 mph through a hairpin.
    >>>

    >> The old road contains the hairpin. The new road is declared a trunk road.
    >>> What would you say the grade is on the section where you
    >>> exceed 60 mph?

    >> 10% maybe less, have to check by map.
    >>>
    >>> Is this the mountain bike trail that I see on the internet
    >>> when I google for bwlch, or is it a road? That is, are we
    >>> talking about a ski-resort dirt-descent specialty-downhill
    >>> or a paved road?

    >> Single carriageway trunk road. Scares the shit outa some.
    >> Motorcyclists coming towards you at 100mph+ dont always return to their
    >> nearside, I guess so they can see around the bend which of course I want to
    >> cut. The lead rider must keep their head up for this reason.
    >> It takes three or four riders riding close to get past 100kmh
    >> TJ Now stop it!
    >>

    >
    > Dear Trevor,
    >
    > If you reveal marvels like this, you can hardly expect
    > people to stop asking for explanations. (I will, however,
    > skip the raised eyebrows about motorcycles routinely
    > climbing such grades at over 100 mph.)
    >
    > For a typical bicycle rider's weight and profile, a long
    > stretch of extremelly rare 15.4% grade is required to reach
    > 60 mph.
    > Heavier riders with improved tucks can do better. Chalo
    > Colina, for example, may be able to reach 60 mph on a mere
    > 6.6% slope, since he enjoys considerably increased force
    > (over 400 pounds with bicycle) without a corresponding
    > increase in wind drag.
    >
    > Pedalling, of course, is unlikely to be of any value. Over
    > 157 rpm is required to pedal 60 mph on a 700c 53x11 and
    > would involve losing more to increased wind drag than could
    > be made up.
    >
    > Perhaps you could check the details again with the other two
    > or three riders involved and persuade them to favor us with
    > a post or two about the maximum recorded on their
    > speedometers?
    >
    > Meanwhile, you might enjoy plugging a few figures into this
    > speed calculator:
    >
    > http://www.analyticcycling.com/ForcesSpeed_Page.html
    >
    > Set the power to 0 watts and the slope to -0.154 and you'll
    > produce a speed of about 60 mph for a 75kg rider and
    > bicycle. Plug in Chalo's 182kg and the result converts to
    > 93.5 mph.
    >
    > I never trust my conversions, so I like to check them here:
    >
    > http://members.aol.com/javawizard/speed.html
    >
    > You can reduce various factors to increase speed, but you'll
    > have to keep them believable. A 10% slope with the defaults
    > produces only 48 mph. Increasing this 25% would be
    > impressive.
    >
    > You may also have some explaining to do in order to convince
    > people that a peloton coasts downhill faster than a single
    > coasting rider. As I understand it, the lead rider works
    > like a dog and those who follow enjoy the reduced wind drag
    > available just behind him.
    > There are regular discussions here about whether the leader
    > benefits slightly from someone filling in his slipstream,
    > but I can't recall anyone claiming an improvement of more
    > than a mile per hour.
    >
    > People do maintain sites reporting impressive climbs and
    > descents for bicyles, so you might want to look into getting
    > your local route listed if it turns out to have a
    > significant stretch of 10% grade.
    > Here are two links to places that list notable climbs:
    >
    > http://www.ulb.ac.be/di/ssd/ldoyen/e/v.html
    >
    > http://www.cyclos-cyclotes.org/altigraph.html
    >
    > Cheers,
    >
    > Carl Fogel
     
  20. On Mon, 9 Aug 2004 14:43:12 -0700, Bill Lloyd
    <[email protected]> wrote:

    >Well I guess in the UK they don't have the altitude, but I've hit 63.5
    >mph in the Sierras in eastern California, descending from north lake
    >Tahoe to Truckee.
    >
    >The grade isn't all that steep, either -- maybe 10%? But it's at 8500'
    >give or take.
    >


    Dear Bill,

    Here are the sites again if you'd like to play with the
    numbers.

    http://www.analyticcycling.com/ForcesSpeed_Page.html

    http://members.aol.com/javawizard/speed.html

    Plugging in -0.10 for the grade, 0 watts for no pedalling,
    and 0.950 for air density around 2600 meters produces a
    terminal speed for the other defaults such as 165 lbs of
    riders and bike of 24.4 meters per second, or 54.5 mph

    To reach 63.5 mph, you need extra power or reduced drag,
    either from a tighter tuck, a steeper grade, a tailwind,
    another vehicle to draft, or a heavier rider.

    Pedalling is generally held to be counter-productive at such
    speeds with ordinary bicycle frames and gearing. At 63.5 mph
    with a 2124mm 700c tire and 53x11 gearing, you must spin up
    to 162 rpm before the chain engages the rear wheel--such
    furious pedalling is likely to add more drag than any useful
    propulsion.

    For example, a 102 kg bike and rider (214 pounds), will
    coast up to 63.5 mph on the hypothetical 10% grade with the
    0.950 air density.

    Or the default 165 lb rider could simply tilt the road to a
    grade of 13.4% at that altitude.

    As an overweight Shetland pony, if not a modest Clydesdale,
    even I could presumably roll my 110 kg carcass and bicycle
    down your 10% grade at 66 mph (assuming that it's nice and
    straight and uncrowded and long enough), so your
    high-altitude claim of 63.5 mph seems quite plausible.

    Drop it down to sea level air density and my 66 mph drops to
    58 mph.

    It should be remembered that many high speed claims may be
    made quite honestly by riders unaware of handsome tail winds
    or the advantage of 40 pounds of baggage. My best speed
    coasting down my daily hill is 15 mph higher than usual, a
    tribute to a fine west wind, while my regular victories over
    a friend in coasting contests down the same hill rely on my
    extra fifteen pounds of ballast, much like any underhanded
    soapbox derby triumph.

    Carl Fogel
     
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