expensive road bikes fussy and unreliable?

Discussion in 'Cycling Equipment' started by Wle, Oct 27, 2003.

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  1. Carl Fogel

    Carl Fogel Guest

    Steve Palincsar <[email protected]> wrote in message news:<[email protected]>...
    > On Wed, 29 Oct 2003 06:35:03 -0500, Simon Brooke wrote:
    >
    > >> that a bit of searching in the archives will turn up some convincing posts from Jobst Brandt
    > >> about how the low-speed, narrow-rpm-range, high-torque human-powered bicycle is pretty much
    > >> stuck with the chain and derailleur system, which as he points out is used by nothing else in
    > >> the mechanical world.
    > >
    > > Yes, but as we've seen in other discussions, Jobst writes with great authority and confidence
    > > about matters on which he is expert, and also writes with great authority and confidence about
    > > matters on which he is blissfully ignorant, so his opinion is not of great utility. Empirically,
    > > epicyclic hub gears work, whatever Jobst may think. They are arguably not as efficient as
    > > deraileurs, and under road conditions are unlikely to displace deraileurs. But off road cycling
    > > is significantly different and the deraileur is working in significantly sub-optimal conditions.

    > And lest we forget, the original post was about a commuting bike. And for many commutes, epicyclic
    > hubs have advantages:
    >
    > - shift when stopped, at a light or stop sign, a big issue for commuters
    > - weather protection, again more likely to be an issue for an every-day commuter than a fair
    > weather recreational rider
    > - less maintenance (certainly true for the old reliable SA, which merely needed oil once in a
    > while) required
    > - may be easier to shift in the dark and in the rain (1 shifter only, simply run up and down the
    > gears, no worries about front shifting)

    Dear Steve,

    Are you and Dave Kerber in cahoots to demonstrate tactful opening lines and point out the practical
    side of things?

    First Dave begins with "Keep in mind" what I obviously forgot and now you're starting with "And lest
    we forget" what never occurred to me.

    Curse you both for a couple of well-mannered, sensible, posters!

    Thanks,

    Carl Fogel
     


  2. Carl Fogel

    Carl Fogel Guest

    David Kerber <[email protected]_ids.net> wrote in message
    news:<[email protected]>...
    > In article <[email protected]>,

    [snip]

    > Keep in mind that a motorcycle chain (or a bike's if it's a single speed) is perfectly in line. I
    > believe it's the bends it makes when you are on chain ring/sprocket combinations which don't allow
    > the chain to be straight, which cost you the most energy losses.
    >
    > A chain and sprocket drive is extremely efficient method of transferring power when everything is
    > correctly aligned.

    Dear David,

    I think that you're right, but I wish that I knew of a good web site that provided the data on the
    power losses. I know that I've seen threads on the matter, but they always seemed to lead to a
    long-ago test of a chain enclosed, perfectly aligned, and carefully tensioned.

    I also vaguely remember that the data was somehow suspect to some engineers who commented on it.
    What I mostly remember is feeling baffled that the tests weren't sitting out in plain sight for
    clods like
    me.

    Sorry if I'm asking where the phone book is in a telephone booth, but do you know of any web site or
    book that addresses this kind of thing?

    (I hope that you don't mind if I borrow your tactful opening line in the future--"Keep in mind" is
    so much better than the "Hey, dummy!" that I deserved.)

    Thanks,

    Carl Fogel
     
  3. [email protected] (wle) writes:

    >i;ve seen it in here, "commuting on a racing bike is hard duty".

    >i don;t want it to break.

    >i don;t want to be replacing parts all the time.

    >i don;t want to be adjusting stuff all the time [the fuji and gt seem to need constant twiddling
    >with derailleurs, spokes/truing, brake cable tension, pedals, it;s always something].

    Something has gone wrong with the road bicycle industry over the past 10 years. There is a backlash
    against today's clipless pedal toy-bikes (to enjoy a bicycle, it should be as convenient to use as
    walking. That means it should accept fenders, racks, toe clips & straps, have a comfortable (perhaps
    real leather) saddle, and have a host of other ideas that have been lost in the past 10 years in the
    bicycle industry ...) Rivendell Bike Works (see www.rivendellbicycles.com) and the Internet-BOB
    mailing list (see www.bikelist.org) personify this philosophy.

    I think by definition some of the most durable componentry is/was the campagnolo nuovo record stuff
    (as long as you stay away from the early titanium components). A lot of that stuff which was made in
    the 1960's and 1970's is still on the road. Some of that is from small parts support, but you also
    have to give it credit as being second to none in durability.

    The level of componentry you are using for your commuter bike (600 and Sora, especially) does not
    have the same durability or precision machining level as campy record. Also, when a part breaks or
    falls off you will have to throw away the component. With campy stuff, every 2-3 years the
    components "shift" down one notch, so Record becomes Chorus, etc. Also, there is small parts support
    for at least 3 years for each of the 3 top lines (Record, Chorus, Centaur). This means you get at
    least 6 years of small-parts support for Campy Record components, for example.

    If you are having adjustment problems with your bicycle, perhaps you should consider selling one or
    both bikes and getting a centaur or chorus bicycle. Alternately, you could get an older nuovo or
    super record bicycle (stay away from titanium pedals and BB's, however.) Campy stuff is not as cheap
    as shimano, but its also not as disposible as shimano. If you _have_ to own a shimano bicycle, then
    you might consider an ultegra bicycle at firesale prices (some can be had for $800 on clearance ...)

    As for rims and spokes, for commuting nothing beats a 500g tandem rim and 14 or 14/15 gauge spokes.
    It doesn't make sense to run high tech stupid-light wheels on a commuter bicycle.

    - Don Gillies San Diego, CA
     
  4. Matt O'Toole

    Matt O'Toole Guest

    "Donald Gillies" <[email protected]> wrote in message news:[email protected]...
    > [email protected] (wle) writes:

    > >i;ve seen it in here, "commuting on a racing bike is hard duty".
    >
    > >i don;t want it to break.
    >
    > >i don;t want to be replacing parts all the time.
    >
    > >i don;t want to be adjusting stuff all the time [the fuji and gt seem to need constant twiddling
    > >with derailleurs, spokes/truing, brake cable tension, pedals, it;s always something].

    I haven't really "twiddled" with my mountain bike for over a year, except to clean and relube the
    chain, and replace it once. And it's my primary transportation and recreation vehicle, since I don't
    own a car.

    > Something has gone wrong with the road bicycle industry over the past 10 years. There is a
    > backlash against today's clipless pedal toy-bikes (to enjoy a bicycle, it should be as convenient
    > to use as walking. That means it should accept fenders, racks, toe clips & straps, have a
    > comfortable (perhaps real leather) saddle, and have a host of other ideas that have been lost in
    > the past 10 years in the bicycle industry ...) Rivendell Bike Works (see
    > www.rivendellbicycles.com) and the Internet-BOB mailing list (see www.bikelist.org) personify this
    > philosophy.

    Yeah, but look at their prices -- hardly what I'd call "practical," or "value."

    I agree about the fenders and racks part, but not about the rest. I hate old-fashioned leather
    saddles (Flites are much more comfortable for me), and I love clipless pedals.

    > I think by definition some of the most durable componentry is/was the campagnolo nuovo record
    > stuff (as long as you stay away from the early titanium components). A lot of that stuff which was
    > made in the 1960's and 1970's is still on the road.

    Where? I'm on the road every day, and I never see it anywhere. I see it hanging in people's garages,
    and being traded by bike nerds on eBay -- but not being ridden. Given the choice, most people will
    take the STI/Ergo/clipless, any day.

    Forget Ti BB axles -- NR and SR cranks broke with alarming regularity, twice under my feeble legs.
    It's not an experience I care to repeat.

    > Some of that is from small parts support, but you also have to give it credit as being second to
    > none in durability.

    I consider it a distant second to Suntour stuff from the same era. And all of it pales compared to
    modern Shimano/Campy, in utility, reliability, and even durability. Older chainrings and cogs lasted
    longer, but derailers and shifters certainly didn't. And most brakes really sucked. Not to mention
    the twiddling -- having to readjust derailers (to a hair) to compensate for wear, and getting the
    friction setting on the shifters exactly right, so they didn't slip. Bah!

    > The level of componentry you are using for your commuter bike (600 and Sora, especially) does not
    > have the same durability or precision machining level as campy record.

    Baloney. Not only that, it doesn't rely on "precision machining" for its function. It's much more
    forgiving of wear -- much better engineered.

    > Also, when a part breaks or falls off you will have to throw away the component. With campy stuff,
    > every 2-3 years the components "shift" down one notch, so Record becomes Chorus, etc. Also, there
    > is small parts support for at least 3 years for each of the 3 top lines (Record, Chorus, Centaur).
    > This means you get at least 6 years of small-parts support for Campy Record components, for
    > example.

    I fail to see the wisdom of replacing $40 derailer pulleys, instead of just replacing the whole
    derailer for $25. The question of STI vs. Ergo serviceability remains a good one, but both are
    reliable enough that it's probably not worth worrying about. I'll take my chances. As far as the
    rest of it goes, I've never had trouble getting Shimano parts, or even parts for long-defunct
    Suntour. Shops that stock Campy are few and far between in the US. So if last minute parts
    replacement is a concern, don't even think about Campy.

    > If you are having adjustment problems with your bicycle, perhaps you should consider selling one
    > or both bikes and getting a centaur or chorus bicycle.

    I'm all for fewer, less hyper-specialized bikes, but you don't need Centaur or Chorus to
    achieve that aim.

    > Alternately, you could get an older nuovo or super record bicycle (stay away from titanium pedals
    > and BB's, however.)

    Sure --buy one cheap at a garage sale, sell it to some bike nerd on eBay, and use the proceeds to
    finance the bike of your choice.

    > Campy stuff is not as cheap as shimano, but its also not as disposible as shimano. If you _have_
    > to own a shimano bicycle, then you might consider an ultegra bicycle at firesale prices (some can
    > be had for $800 on clearance ...)

    Yeah, right, with some crappy stupidlight aluminum frame, an awful saddle with a hole in it, and
    poorly-built wheels.

    Campy *bikes* are usually not as cheap as Shimano, but if you're buying grouppos separately the
    prices are close, with Campy sometimes being cheaper.

    I just got a good deal on an Ultegra bike, but I can't say it's any better than a Tiagra bike. It's
    shinier, a little lighter, and will have better resale value should I need to unload it. So for a
    little more money it was worth it, but I certainly wouldn't have paid twice as much. Personally I
    draw the line at Sora shifters because I can't reach the thumb lever from the drops, but other than
    that they're fine too.

    > As for rims and spokes, for commuting nothing beats a 500g tandem rim and 14 or 14/15 gauge
    > spokes. It doesn't make sense to run high tech stupid-light wheels on a commuter bicycle.

    On that, we agree. Don't forget 25mm or larger tires.

    Matt O.
     
  5. Jay Beattie

    Jay Beattie Guest

    "Matt O'Toole" <[email protected]> wrote in message
    news:RHeob.24151$%[email protected]...
    >
    > "Donald Gillies" <[email protected]> wrote in message news:[email protected]...
    > > [email protected] (wle) writes:
    >
    > > >i;ve seen it in here, "commuting on a racing bike is hard duty".
    > >
    > > >i don;t want it to break.
    > >
    > > >i don;t want to be replacing parts all the time.
    > >
    > > >i don;t want to be adjusting stuff all the time [the fuji and gt seem to need constant
    > > >twiddling with derailleurs, spokes/truing, brake cable tension, pedals, it;s always something].
    >
    > I haven't really "twiddled" with my mountain bike for over a year,
    except to
    > clean and relube the chain, and replace it once. And it's my primary transportation and recreation
    > vehicle, since I don't own a car.
    >
    > > Something has gone wrong with the road bicycle industry over the
    past
    > > 10 years. There is a backlash against today's clipless pedal toy-bikes (to enjoy a bicycle, it
    > > should be as convenient to use as walking. That means it should accept fenders, racks, toe clips
    > > & straps, have a comfortable (perhaps real leather) saddle, and have a host of other ideas that
    > > have been lost in the past 10 years in the bicycle industry ...) Rivendell Bike Works (see
    > > www.rivendellbicycles.com) and the Internet-BOB mailing list (see www.bikelist.org) personify
    > > this philosophy.
    >
    > Yeah, but look at their prices -- hardly what I'd call "practical," or
    "value."
    >
    > I agree about the fenders and racks part, but not about the rest. I
    hate
    > old-fashioned leather saddles (Flites are much more comfortable for
    me), and I
    > love clipless pedals.
    >
    > > I think by definition some of the most durable componentry is/was
    the
    > > campagnolo nuovo record stuff (as long as you stay away from the
    early
    > > titanium components). A lot of that stuff which was made in the 1960's and 1970's is still on
    > > the road.

    Or, in my case, collecting dust in the basement. I will probably ressurect a pair of brakes to
    re-build a fixed gear commuter (not withstanding my prior posts about the hills between my house and
    work), but other than that, the rest of the stuff sits and rots -- along with the one-arm crank sets
    because the other ones broke.
    >
    > Where? I'm on the road every day, and I never see it anywhere. I see
    it
    > hanging in people's garages, and being traded by bike nerds on eBay --
    but not
    > being ridden. Given the choice, most people will take the
    STI/Ergo/clipless,
    > any day.
    >
    > Forget Ti BB axles -- NR and SR cranks broke with alarming regularity,
    twice
    > under my feeble legs. It's not an experience I care to repeat.

    But I never crashed! A real point of pride for me -- all three or four times.

    > > Some of that is from small parts support, but you also have to give it credit as being second
    to
    > > none in durability.
    >
    > I consider it a distant second to Suntour stuff from the same era.
    And all of
    > it pales compared to modern Shimano/Campy, in utility, reliability,
    and even
    > durability. Older chainrings and cogs lasted longer, but derailers
    and shifters
    > certainly didn't. And most brakes really sucked. Not to mention the twiddling -- having to
    > readjust derailers (to a hair) to compensate
    for wear,
    > and getting the friction setting on the shifters exactly right, so
    they didn't
    > slip. Bah!

    See, this is where I disagree. Old NR parts (except cranks and BB spindles) really did last forever.
    I have worn out more modern Shimano derailleurs. The hubs died at about the same rate as modern hubs
    (however, I just ripped the flange off a relatively new Ultegra!). I will suffer the reduced
    derailleur longevity for the convenience of STI/Ergo, however, and longevity beyond a certain point
    really makes no difference in todays market anyway.

    The deal with old NR is that the seals were non-existent. Shimano seals are far superior, and the
    plug and play cartridge BBs and headsets are essentially maintenance free. Living in a wet climate,
    the last thing I want to do is be constantly repacking bearings. There is nothing to miss about the
    old NR equipment performance-wise, although you could have bad performance (by todays' standards)
    for a very long time. -- Jay Beattie.
     
  6. Hugh Fenton

    Hugh Fenton Guest

    "Donald Gillies" <[email protected]> wrote in message news:[email protected]wcastle.cs.ubc.ca...
    > [email protected] (wle) writes:
    >
    > >i;ve seen it in here, "commuting on a racing bike is hard duty".
    >
    > >i don;t want it to break.
    >
    > >i don;t want to be replacing parts all the time.
    >
    > >i don;t want to be adjusting stuff all the time [the fuji and gt seem to need constant twiddling
    > >with derailleurs, spokes/truing, brake cable tension, pedals, it;s always something].
    >
    > Something has gone wrong with the road bicycle industry over the past 10 years. There is a
    > backlash against today's clipless pedal toy-bikes (to enjoy a bicycle, it should be as convenient
    > to use as walking. That means it should accept fenders, racks, toe clips & straps, have a
    > comfortable (perhaps real leather) saddle, and have a host of other ideas that have been lost in
    > the past 10 years in the bicycle industry ...) Rivendell Bike Works (see
    > www.rivendellbicycles.com) and the Internet-BOB mailing list (see www.bikelist.org) personify this
    > philosophy.
    >
    >
    > As for rims and spokes, for commuting nothing beats a 500g tandem rim and 14 or 14/15 gauge
    > spokes. It doesn't make sense to run high tech stupid-light wheels on a commuter bicycle.
    >
    > - Don Gillies San Diego, CA

    Seriously, if you're ever in Denmark, drop into a decent bike shop. Cycling is serious there -
    bicycles are not a toy. Look at the components - totally different from what you get in my local
    Australian bike shop - designed for longevity and practicality.

    Okay, okay, I'm a luddite - my main ride is still a Suntour equipped Cadex ALM1 MTB - 4 continents
    and counting.

    Hugh Fenton
     
  7. In article <[email protected]>, "Hugh Fenton" <[email protected]> wrote:

    > "Donald Gillies" <[email protected]> wrote in message news:[email protected]...
    > > [email protected] (wle) writes:
    > >
    > > >i;ve seen it in here, "commuting on a racing bike is hard duty".
    > >
    > > >i don;t want it to break.
    > >
    > > >i don;t want to be replacing parts all the time.
    > >
    > > >i don;t want to be adjusting stuff all the time [the fuji and gt seem to need constant
    > > >twiddling with derailleurs, spokes/truing, brake cable tension, pedals, it;s always something].
    > >
    > > Something has gone wrong with the road bicycle industry over the past 10 years. There is a
    > > backlash against today's clipless pedal toy-bikes (to enjoy a bicycle, it should be as
    > > convenient to use as walking. That means it should accept fenders, racks, toe clips & straps,
    > > have a comfortable (perhaps real leather) saddle, and have a host of other ideas that have been
    > > lost in the past 10 years in the bicycle industry ...) Rivendell Bike Works (see
    > > www.rivendellbicycles.com) and the Internet-BOB mailing list (see www.bikelist.org) personify
    > > this philosophy.
    > >
    > >
    > > As for rims and spokes, for commuting nothing beats a 500g tandem rim and 14 or 14/15 gauge
    > > spokes. It doesn't make sense to run high tech stupid-light wheels on a commuter bicycle.
    > >
    > > - Don Gillies San Diego, CA
    >
    > Seriously, if you're ever in Denmark, drop into a decent bike shop. Cycling is serious there -
    > bicycles are not a toy. Look at the components - totally different from what you get in my local
    > Australian bike shop - designed for longevity and practicality.
    >
    > Okay, okay, I'm a luddite - my main ride is still a Suntour equipped Cadex ALM1 MTB - 4 continents
    > and counting.
    >
    > Hugh Fenton

    If you guys are having troubles keeping your bikes in tune, that's super, but it's quite easy to
    build a relatively trouble-free bike that will do everything from commuting to casual racing. I did
    it, using a Pinarello as my commuter/race rig for almost a year. For a few reasons, I'm now using a
    junky Bianchi for my winter bike (a major reason is that I want to minimize salt corrosion on the
    Pinarello, so I use a bike that I won't care about losing to rust; I got the Bianchi for $10, so if
    it gets lost/stolen/too rusty, the biggest expense will be the time to acquire a new one).

    A road bike, once well-adjusted, should take no more maintenance than any other bike. Indexed
    shifting has added one complication in synchronizing derailleur position at index points with cogs,
    but that tends to be adjust-and-forget for admirably long intervals. As for having to repeatedly
    true spokes, adjust cable tension, and pedals, I have no idea what you're doing. Build the wheels
    right the first time, eschew badly-conceived boutique wheels, and live your life.

    I think the real problem you may have is that the stuff you are railing against is mostly of
    genuine benefit in bike racing: No roadie will give up STI or clipless pedals because they have
    obvious benefits over the old ways for racers, and are nice for the rest of us, too. Toe clips
    involve so much stoplight fussing that I gladly reach for my special shoes. While I don't have much
    truck with low-spoke-count wheels, there are benefits to more aero wheels, which aren't necessarily
    the same thing.

    Your point about seats makes no sense. I'm not a long-distance rider, but I use a tiny but
    comfortable seat for most of my longer rides, and it has taken me on every ride I wanted to do so
    far, which has maxed out at a metric century.

    Given that the boys in the peloton tend to spend 7 hours on their bike at a time, and do that almost
    every day of the year, I'd say that the racy seats that result are certainly comfy enough. I think
    most pro riders would "spend" an extra 100 grams on their seat to prevent it from being
    uncomfortable, but they don't because skimpy seats are comfortable, as long as they fit your sit
    bones. If a Brooks makes you feel better, go for it. But don't assume the guys with plastic seats
    like me are in pain.

    Where toy bikes do let down a serious cyclist tends to be in their lack of fender clearance and
    rack-worthiness, but there's no market for these in North America, because of the surplus of fendery
    and rack-ready bikes.

    The nature of the modern market on this continent is that anyone who wants can have a really good,
    reliable, fender-friendly 20-year-old road bike can have one for practically nothing. I picked up
    two really decent bikes yesterday, sitting beside a bike store's dumpster, presumably dropped off by
    someone who couldn't sell them to the store or thought they would most easily find a good home
    there. So few people appreciate the virtues of these widely-produced mid-grade road bikes that there
    is a ludicrous surplus of them left for those of us who care. Those few people who do want a cheap
    old bike gravitate to old mountain bikes, leaving the good stuff for me.

    Only when you get into recent technologies like brifteurs do bike components start to have value.

    A Rivendell or Surly to get fender clearance and rackiness? these are the real jokes of the bike
    world. They're competing with 20-year old technology by offering innovations like "no rust" and
    "fancy lugs", or possibly "don't need a tune-up when you buy it". And they're offering these
    features at prices that would make a lot of road bikes blush. Who needs that?

    Railing against the bike industry because they generally don't deign to compete with "free" is
    silly. All the stuff you treasure on a bike was there years ago, and those bikes didn't go away.
    Indeed they so didn't go away that my first good road bike was a 20-year-old garage sale find, my
    most recent commuter is a 20-year-old garage sale find, and I found two more yesterday, and if I was
    motivated and had $20 I could probably get two more in the next four hours.

    I appreciate the performance gain (which admittedly come more from components like shifters than
    making low-clearance forks) that a nice modern race bike offers, but paying good money for a careful
    replica of a bike I bought for $10 confuses me.

    --
    Ryan Cousineau, [email protected] http://www.sfu.ca/~rcousine President, Fabrizio Mazzoleni Fan Club
     
  8. Simon Brooke

    Simon Brooke Guest

    Ryan Cousineau <[email protected]> writes:

    > I think the real problem you may have is that the stuff you are railing against is mostly of
    > genuine benefit in bike racing: No roadie will give up STI or clipless pedals because they have
    > obvious benefits over the old ways for racers, and are nice for the rest of us, too. Toe clips
    > involve so much stoplight fussing that I gladly reach for my special shoes.

    Absolutely, could not agree more. Clip-less pedals are just a Good Thing - especially SPDs, where
    the cleat doesn't project below the tread of your shoe and so consequently cleats can be fitted to
    quite normal shoes that it's comfortable to wear all day. They're so much easier to use than
    toestraps - and in my opinion a good deal safer. Reaching down to tighten or loosen your straps is
    something I can well do without.

    > Given that the boys in the peloton tend to spend 7 hours on their bike at a time, and do that
    > almost every day of the year, I'd say that the racy seats that result are certainly comfy enough.
    > I think most pro riders would "spend" an extra 100 grams on their seat to prevent it from being
    > uncomfortable, but they don't because skimpy seats are comfortable, as long as they fit your sit
    > bones. If a Brooks makes you feel better, go for it. But don't assume the guys with plastic seats
    > like me are in pain.

    Saddles are very personal, of course. And there area lot of 'boutique' saddles out there which don't
    look to me as if they'd be comfortable for anyone. Brook saddles make _me_ feel better, but I don't
    tend to recommend them to friends because in my experience most people don't like 'em.

    For the rest of it I generally agreed with pretty much all of your post. You can do pretty well on
    an inexpensive racing-style road bike, both for commuting and for just general getting around the
    place, and it'll stand a reasonable amount of abuse. The rims on my road bike (which does not have a
    rack or fenders) are beginning to go now, and the wheels will have to be rebuilt soon; but they
    aren't out of true and have never been trued since I built them ten years ago.

    --
    [email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/

    X-no-archive: No, I'm not *that* naive.
     
  9. Gary Young

    Gary Young Guest

    [email protected] (wle) wrote in message news:<[email protected]>...
    > i;ve seen it in here, "commuting on a racing bike is hard duty".
    >
    > but, if you are not really pounding the pedals, it seems to me that the only hard thing is
    > mileage.
    >
    > my one way trip is 13 miles.
    >
    > i have a couple of mid price road/race bikes.
    >
    > a. 2002 fuji finest with sora group
    > b. 1996 or so gt edge with 600 group
    >
    > what is about commuting that is supposed to be so hard?
    >
    > it;s just miles.
    >
    > i don;t weigh a lot.
    >
    > what is it that is supposed to be wearing out?

    There is probably no reason you can't commute with your road bike. I use a touring bike because I
    like to run fat tires, but if you don't weigh a lot you can probably get by with skinnier tires
    just fine.
    >
    > i have had some spokes break on the fuji [alex rims da-22 i think] but overall, it seems fine
    > after 5100 miles.

    Your wheels were probably poorly built. Make sure your wheels are built the way Jobst Brandt
    recommends in the Bicycle Wheel and you shouldn't have problems. As long as your tires are big
    enough to avoid pinch flats and bent rims, you shouldn't have to fiddle with your wheels even if you
    are riding potholed streets.

    >
    > the gt, i have not ridden as much.
    >
    > the important question though, is, if commuting is hard, and i don;t want to ride a bike over 22
    > lbs with pedals, what to buy?
    >
    > i don;t want it to break.
    >
    > i don;t want to be replacing parts all the time.
    >
    > i don;t want to be adjusting stuff all the time [the fuji and gt seem to need constant twiddling
    > with derailleurs, spokes/truing, brake cable tension, pedals, it;s always something].

    I suppose you could go to friction shifting, a hub gear or a fixed gear to remedy twiddling with
    your derailleurs, but I'm curious about what your problems are. I'm a latecomer to indexing, and
    expected it to be fussy. Instead, I've found it amazingly robust. Sheldon Brown speaks highly of the
    Sora stuff, particularly the shifters.

    My impression is that modern dual-pivot brakes are less fiddly than older single-pivot brakes, which
    were harder to keep centered. I suppose dual pivots require more frequent adjustment to compensate
    for pad wear though.

    >
    > but if you start spending over a certain amount, maybe 1000 or so, the focus starts being on
    > weight reduction, exclusively.
    >
    > it seems reliability is not the main thing any more, over a certain price.
    >
    > the assumption being that you would be 'racing' the bike and don;t mind fiddling with it, and it;s
    > ok if it only lasts 10000 miles before bearings, freewheels, chain rings, bottom brackets, wheels,
    > etc. [expensive stuff], start giving up.
    >
    > i don;t think i want a 'touring bike', too heavy.
    >
    > so, under 22 lbs, last at least 25,000 miles, don;t have to fiddle with it all the time,
    > what to get?
    >
    > not that i would do it til my current bikes are still alive but still, it seems like a question no
    > one wants to answer..
    >
    > wle.
     
  10. On Wed, 29 Oct 2003 19:35:02 GMT, Simon Brooke <[email protected]>
    wrote:
    >[email protected] (Carl Fogel) writes:

    >> I suppose that I'm just mesmerized by the evil rule of thumb from my motorcycling days that a
    >> good chain loses about 3% of the engine's power, while each gear-to-gear interface loses about
    >> 5%. Perhaps I'm mistaken on the power losses involved.
    >
    >Well, that's the rule of thumb I learned too; so the minimum loss in the gearbox is about 8%, which
    >is not good. But this does not mean it's a non-starter, just that the engineering needs to be good.
    >Engineering is always about trade-offs.

    I don't think there's any way it can possibly be the case in all gear-gear situations, though. Cars
    & trucks all have gearboxes, which usually have more than one gear/gear interface in the power
    train, and the bigger engines can easily put a couple hundred kilowatts through them. That'd leave
    them with somewhere between 3 and 10 kW of heat to disperse, and the mechanisms for doing that just
    aren't in evidence.

    The whole oil-bath thing may be a factor there, but doesn't the Rohloff do that as well?

    Jasper
     
  11. Carl Fogel

    Carl Fogel Guest

    Jasper Janssen <[email protected]> wrote in message news:<[email protected]>...
    > On Wed, 29 Oct 2003 19:35:02 GMT, Simon Brooke <[email protected]> wrote:
    > >[email protected] (Carl Fogel) writes:
    >
    > >> I suppose that I'm just mesmerized by the evil rule of thumb from my motorcycling days that a
    > >> good chain loses about 3% of the engine's power, while each gear-to-gear interface loses about
    > >> 5%. Perhaps I'm mistaken on the power losses involved.
    > >
    > >Well, that's the rule of thumb I learned too; so the minimum loss in the gearbox is about 8%,
    > >which is not good. But this does not mean it's a non-starter, just that the engineering needs to
    > >be good. Engineering is always about trade-offs.
    >
    > I don't think there's any way it can possibly be the case in all gear-gear situations, though.
    > Cars & trucks all have gearboxes, which usually have more than one gear/gear interface in the
    > power train, and the bigger engines can easily put a couple hundred kilowatts through them. That'd
    > leave them with somewhere between 3 and 10 kW of heat to disperse, and the mechanisms for doing
    > that just aren't in evidence.
    >
    > The whole oil-bath thing may be a factor there, but doesn't the Rohloff do that as well?
    >
    > Jasper

    Dear Jasper,

    I fear that the drive-train losses are true.

    That is, given 400 real horsepower at the crankshaft, I won't be surprised if people who know about
    cars tell me that 20 horsepower (5%) or more is lost on the way to the drive-shaft.

    The massive metal structure surrounding it all and the oil bath may well be enough to cool
    things off.

    One of the nicest things about switching from two-stroke air-cooled trials bikes in the 1970's to
    an four-stroke Honda trials bike was that the overheating problem vanished. The Honda has some
    cooling fins, but they're little more than thong bikinis, a gesture toward decency. What kept the
    beast cool, apart from four-stroke versus two-stroke, was twenty pounds of extra metal in the form
    of the overhead valve train acting as a radiator and what was essentially a crude two-quart oil-
    cooling system.

    Five quarts or more of oil pumping through a water-cooled car engine will draw off a lot of heat--
    which the radiator handles nicely.

    Despite all this, you may turn out to be right about the losses being much smaller for large
    engines. I vaguely recall someone explaining in this newsgroup (possibly in connection with chains)
    that some sort losses were fixed, so the initial losses were distressingly high, but then rapidly
    reduced as power increased.

    That is, at 100 watts, 10 watts of power was wasted, a 10% inefficiency. But this 10 watts was
    almost all the power that was going to be lost. At 200 watts with the same 10 watts lost, the
    inefficiency dropped to 5%.

    This might be the case with transmissions handling hundreds of horsepower. An initial loss of 5% to
    8% below a hundred horsepower might stay fixed at that point, even as hundreds of additional
    horsepower are added. If so, then you'd be right.

    Let's hope that someone who knows what happens will explain things to us.

    Carl Fogel
     
  12. Bruni

    Bruni Guest

    While the non-linearity thing may remain unresolved, I can add that in the interest of quiet, the
    helical cut gears of auto trannies eat the watts. Rholoff uses straight cut ones. Also the fluid
    churning losses are non-linear with speed and much faster in the auto. tom

    --
    Bruni Bicycles
    "Where art meets science"
    brunibicycles.com
    410.426.3420
    Carl Fogel <[email protected]> wrote in message
    news:[email protected]...
    > Jasper Janssen <[email protected]> wrote in message
    news:<[email protected]>...
    > > On Wed, 29 Oct 2003 19:35:02 GMT, Simon Brooke <[email protected]>
    > > wrote:
    > > >[email protected] (Carl Fogel) writes:
    > >
    > > >> I suppose that I'm just mesmerized by the evil rule of
    > > >> thumb from my motorcycling days that a good chain loses
    > > >> about 3% of the engine's power, while each gear-to-gear
    > > >> interface loses about 5%. Perhaps I'm mistaken on the
    > > >> power losses involved.
    > > >
    > > >Well, that's the rule of thumb I learned too; so the minimum loss in
    > > >the gearbox is about 8%, which is not good. But this does not mean
    > > >it's a non-starter, just that the engineering needs to be
    > > >good. Engineering is always about trade-offs.
    > >
    > > I don't think there's any way it can possibly be the case in all
    gear-gear
    > > situations, though. Cars & trucks all have gearboxes, which usually have
    > > more than one gear/gear interface in the power train, and the bigger
    > > engines can easily put a couple hundred kilowatts through them. That'd
    > > leave them with somewhere between 3 and 10 kW of heat to disperse, and
    the
    > > mechanisms for doing that just aren't in evidence.
    > >
    > > The whole oil-bath thing may be a factor there, but doesn't the Rohloff
    do
    > > that as well?
    > >
    > > Jasper
    >
    > Dear Jasper,
    >
    > I fear that the drive-train losses are true.
    >
    > That is, given 400 real horsepower at the
    > crankshaft, I won't be surprised if people
    > who know about cars tell me that 20 horsepower
    > (5%) or more is lost on the way to the drive-shaft.
    >
    > The massive metal structure surrounding it all
    > and the oil bath may well be enough to cool things
    > off.
    >
    > One of the nicest things about switching from
    > two-stroke air-cooled trials bikes in the 1970's
    > to an four-stroke Honda trials bike was that
    > the overheating problem vanished. The Honda has
    > some cooling fins, but they're little more than
    > thong bikinis, a gesture toward decency. What kept
    > the beast cool, apart from four-stroke versus
    > two-stroke, was twenty pounds of extra metal in
    > the form of the overhead valve train acting as a
    > radiator and what was essentially a crude two-quart
    > oil-cooling system.
    >
    > Five quarts or more of oil pumping through a
    > water-cooled car engine will draw off a lot
    > of heat--which the radiator handles nicely.
    >
    > Despite all this, you may turn out to be right
    > about the losses being much smaller for large
    > engines. I vaguely recall someone explaining in
    > this newsgroup (possibly in connection with
    > chains) that some sort losses were fixed, so
    > the initial losses were distressingly high,
    > but then rapidly reduced as power increased.
    >
    > That is, at 100 watts, 10 watts of power was
    > wasted, a 10% inefficiency. But this 10 watts
    > was almost all the power that was going to be
    > lost. At 200 watts with the same 10 watts lost,
    > the inefficiency dropped to 5%.
    >
    > This might be the case with transmissions handling
    > hundreds of horsepower. An initial loss of 5% to 8%
    > below a hundred horsepower might stay fixed at that
    > point, even as hundreds of additional horsepower
    > are added. If so, then you'd be right.
    >
    > Let's hope that someone who knows what happens
    > will explain things to us.
    >
    > Carl Fogel
     
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