Conference noted::bicycle

Mike,

A bit of advise. Don't worry about the wheels if they work. The bike cost less new
than my cranks cost me for my bike. Quality will never be there in a bike
this cheaply made, and for the money spent you can't expect it.

The old saying comes to mind, "Don't throw good money after bad."

Don't invest on fixing these types of bikes up. Your return will be low, very low.
Just keep it running without spending any money and use the money towards
something worth fixing up. Otherwise you'll be spending money on these types of 
bikes almost every time you come in from a ride. They don't hold up to real use.

Tom

    
    An interesting note, Mike.
    
    Well, truing should put the rim in the plane of the axle.
    I suppose a more general notion of "truing" would mean to put
    the rim in *some* plane, independent of orientation to the axle,
    but aside from the fact that that's not desirable, the *process*
    by which one normally trues wheels results in axial plane.  Namely,
    you spin the wheel (on the axle), and iron out side-to-side variances.
    Spinning-the-wheel-on-the-axle means the truing process will orient
    the rim in the axial plane.  Bored yet with my explanation? :-)
    
    (Of course this assumes that the axle isn't bent, otherwise it makes
    a cone, not a plane... ok, a plane is a degenerate cone, I guess.)
    
    Of more concern is *dishing* - the offset of the rim from rotating
    in a plane midway between the hub's flanges.  Dishing is achieved
    by having the spokes on one side of the wheel shorter than those on
    the other side (or making them so by tightening on side's spokes more).
    If each spoke has the same tension as the spokes on its side, then the
    wheel should be true and round, but "dished" to one side or another.
    (Dishing is used to make room for the freewheel in the rear wheel,
    while keeping the rim centered w.r.t. the bike frame.)
    
    As always, for an even more erudite :-) look at bike-wheel theory,
    there's Jobst Brandt's book called "The Bicycle Wheel."
    
    -john

    Do not rule out just plain quality in the manufacture (specifically
    threading) of either the freewheel or the hub. They wheel may be
    perfectly trued/dished and you can still have that rising/wobble effect
    from the freewheel.
    
      My $.02
    
     P.S. No real impact on that kind of bike and or use.

    
    Tom;
    	You're absolutely correct..I've got about $90 in this bike and
    that's what I'll get for it when I sell it. It already served it's
    purpose- which is to get me in a bike-thinking mode and off the couch.
    I don't intend to sink any more $$ into it. 
    	Actually I've got a prospect looking at buying a 4-wheeler I own
    and I've got a litter of pups that will be ready for sale in 5 weeks,
    so I'm getting closer to getting something much nicer to ride. Now
    comes the fun part- looking for deals and trying out various bikes.
    The choices are mind-boggling; I've seen SUSPENSIONS! which is nothing
    like I remember from my younger days; carbon vs. aluminum vs.
    chrome-moly frames (no I don't know yet what the inherent
    advantages/disadvangates are-hmm... maybe a topic for another note?); 
    all sorts of shifters - nothing like the 3-speed Sturmy-Archer I used to 
    have! So I've got a lot of fun learning and checking-out ahead.
    
    John;
    	Yes, your explanation does make sense and I can see how a bent axle
    would create a cone-shaped rotation. I think I can also see how a few
    tight spokes on the top of one side coupled with a few loose spokes at
    the bottom of the same side could have a similar effect..Interesting
    stuff. Thanks for the info!

    Would a bent axle really cause the wheel to wobble?
    After all, the axle doesn't turn.

    (Loose bearings might do it, but I don't think the axle would.)

    -Jeff

    >Would a bent axle really cause the wheel to wobble?
    >After all, the axle doesn't turn.

    I don't know if it would make it wobble but a bent axle could
    cause the wheel to not line up properly with the bike frame and 
    front wheel. Therefore, the bike might tend to drift to one side
    or the other once the gyroscopic effect take place when the wheel
    is spinning. I think I read this could damage your knees over a period
    on time.  


    Huey

>    I don't know if it would make it wobble but a bent axle could
>    cause the wheel to not line up properly with the bike frame and 
>    front wheel. Therefore, the bike might tend to drift to one side
>    or the other once the gyroscopic effect take place when the wheel
>    is spinning. I think I read this could damage your knees over a period
>    on time.  

    Not to mention the "butterfly effect" on the world's climate,
    due to the difference in convection when you leave two tire prints
    instead of one. (:-)

In case the previous reply wasn't a joke:
    The gyroscpic effects aren't big enough to come into play.
    Try puting your wheel in misaligned sometime and see if you can tell.

-Jeff

    re .4:
    
    >Now comes the fun part- looking for deals and trying out various bikes.
    >The choices are mind-boggling; I've seen SUSPENSIONS! which is nothing
    >like I remember from my younger days; carbon vs. aluminum vs.
    >chrome-moly frames (no I don't know yet what the inherent
    >advantages/disadvangates are-hmm... maybe a topic for another note?); 
    >all sorts of shifters - nothing like the 3-speed Sturmy-Archer I used
    >to  have! So I've got a lot of fun learning and checking-out ahead.
    
    This is one of the enjoyable things about hobbies - LEARNING...  I
    heartily recommend this notesfile as a source of information on all 
    kinds of bike related things...  Just sit down in the spare time and
    start searching.  When I started a couple years ago I went through a
    directory of the whole file and it helped immeasurably.  Of course you
    have to pick your information out of the wealth of "holy wars",
    tongue-in-cheek comments, and sometimes "slight exagerations"...  BUT,
    at least you have a wide variety of information - which HAS to be
    accurate since if anyone put in something that was total bull^%$#, 85
    people would immediately verbally pummel them.  :^)  Enjoy!

>    Not to mention the "butterfly effect" on the world's climate,
>    due to the difference in convection when you leave two tire prints
>    instead of one. (:-)

>In case the previous reply wasn't a joke:
>    The gyroscpic effects aren't big enough to come into play.
>    Try puting your wheel in misaligned sometime and see if you can tell.

Gees Jeff,

I only took a guess at the previous question. Since I am not sure how the
butterflies and two tire marks would correlate to each other on the effect of
the world climate, I guess I should leave it up to the ones who knows the
answer to that question. :-)   

I figured since most axles are probably bent near the cone nuts of the wheel.
The would be mounted on a a slight angle. Since you will notice a slight force
when you tilt a spinning wheel to one side or the other when you're holding it
with your fingers,  I would think this force would be enough to make the bike
drift to one side all the time when a bent axle is mounted on a bike. I don't
think the wheel would wobble as long at the cones are properly adjusted. 

Remember, this is a Hypothesis. I will mount a bent axle on my bike tomorrow
at the shop to test out the theoretical value and maybe compute the
experimental error differences. (That's a joke)
                            
Dave

>Since you will notice a slight force
>when you tilt a spinning wheel to one side or the other when you're holding it
>with your fingers,  I would think this force would be enough to make the bike
>drift to one side all the time when a bent axle is mounted on a bike.

This is true... but try the experiment again.

The gyrosopic forces only happen when you are changing the direction
that the axle is pointing.  You get all sorts of precession effects
while you are changing the tilt of the wheel, but not if you hold it
at a steady amount of tilt.

It seems to me that with a bent axle, you would get a bit of force to
one side as you crested a hill, and a bit to the other side as you
bottom out in a valley.

One of these days I'll have to put my wheel in crooked
and see if I can feel it.

-Jeff Bell

    I have a friend that has a diamondback Mountain Bike. He is new to
    riding and has bent his rear axle twice already. The first time his
    quick release broke and that is how we found the axle was bent, we
    brought the bike to the bike shop and they replaced the axle. After
    that his real wheel started making bearing noise and got loader during
    the past couple of weeks. So I took the bike down to the shop again and
    they took a look at it and the new axle is now bent. They did tighten
    the assembly and the noise seems to be better. 
    
    So any ideas as to why the axle would bend again. He is 200lb but the
    riding is not that extreme, just some single track with a lot of rocks
    and roots. Could it be that he is sitting on his seat to much instead
    of putting the weight on the peddles while riding over rough stuff. 
    
    Thanks
    
    Alan

Wow! he broke the quick release? He must be putting some serious stress on the 
bike. A bent axle is common with the old 7 speed freewheel hubsets. They started
using cassette hubs to get the bearings closer to the dropouts. This helps keep
the axle from bending. 

Tell him to try getting his dropouts checked to see if they are aligned. This 
can also cause the axle to bend.

Sometimes a cheap way out is to replace the quick release axle with a solid one,
and throw a box wrench in the tool bag. 

Tom

    It would seem that overtightening a quick-release would also bend the
    rear axle.  Your friend have gorilla-tendencies?

If the axle extends too far out past the cone-nuts (i.e. the threaded
portion extends almost all the way to the outside of the dropout when
the wheel is in the frame) the axles can be bent fairly easily. When this
happens, the QR lever may be actually tightening against the end of the
axle instead of the outside of the dropout, effectively leaving the axle
floating....                 
                       ken