Conference noted::bicycle

    
    	Most likely is that it's your crank. Try loosening it a hair,
    then retightening. It that doesn't work, remove it to check for dirt or
    grit between the taper of the spindle and the crank, then replace and
    retighten. It takes a significant amount of torque to tighten it up,
    but too much can crack the crank. Second choice is your bottom bracket.
    Sometimes the adjusting nut loosens; sometimes you need to put some
    anti-sieze compound on the BB threads before you install it (especially
    if you have dissimilar metals; like a steel BB in an aluminum shell).

    Just had my road bike in the shop for a similar noise.  They found the
    bottom bracket cartridge had come loose.  
    
    First thing though is to check that the crank arms themselves are
    tight, they have a tendency of working loose or it could be your
    pedals.
    
    /ron

    I had that problem when I first got my bike.  I used to just tighten the
    brank nuts and it would stop.  it got to a point where this didn't work
    however, and after taking it in found that I needed a new B.B.  The old
    one was just shot after 4 years of abuse.  The noise still didn't leave
    tho', so I tried tightening the allen bolts connecting the chain rings
    to the crank.....this finally worked. Hope this helps.
    
    	Mike 

>    I had that problem when I first got my bike.  I used to just tighten the
>    brank nuts and it would stop.  it got to a point where this didn't work
    
    I mean "crank" nuts :-)

    Do you have a "naked" bike or do you have things installed like a
    carrier?
    In the last weeks we (group of three long distance riders) expirienced 
    similar problems on two bikes. We also first checked all the normal
    stuff you check in such a case like B.B., pedals, chain....
    and in both cases we find (after some days) out that the carrier was
    the problem ....
    With that experience I think that such a nonperiodicaly noise won't
    be some of the bearings or chain in most cases. Failures in this area
    should produce a regular noice.
    So, if you have a carrier installed, I would first stripe down the bike
    to a naked one before starting readjusting all bearings and have a look
    if it disappears.
    
    servus
    Otto

    what's a carrier?
    
    ed

    Dictonaries....
    
    It's the thing mounted over the backwheel where you can fix some
    smaller baggege on it...
    
    otto

    oh, a rack!  I should have known, I suppose.
    
    ed

Isn't it one of those little grey and white dogs that chase bikes??

Oh, you said 'Carrier'...Never mind

Bob

    As of this morning, my bike's making a periodic ticking sound.  It
    happens whether I'm pedaling or coasting and is once per wheel
    revolution.
    
    When I put more weight on the handlebars, it gets quieter.  I suspect
    that this means it's originating in the rear wheel.
    
    Loose spoke? or what else should I check?
    
    Thanks.
    Erik

    could be spoke flex in the rear wheel where the spokes intersect.  Not
    sure what the "right" fix is but once the guilty spokes have been
    identified I found putting a dab of grease at the intersection got rid
    of the noise.  Could be that the spokes are a little loose or maybe to
    worn and need replacement (I never replaced them for that reason though).  
    
    I also had a much stranger instance of the tick noise.  Turned out that
    the guilty intersection was at the rim where the spoke screws in.  My
    biking friend clued me into this as a possibility as I tried lots of
    other things without success.   He was right.  A dab of oil in the
    spoke hole around the spoke and no noise.  
    
    
     Good luck,
    Larry
    

heres another 'once per revolution' potential culprit:
   the sensor and magnet for your -i assume you have one- cyclometer are hitting
   a second related item is one spoke loose enough to hit sensor each time by

--roger

    do have a freewheel or a cassette?
    
    Chip

    re: .13       I'm embarrassed to say that I have absolutely no idea.
    
    The following may be related.  On Sunday, I rode about 31 miles.  I
    fixed a flat on the rear before starting out and, before putting the
    rear wheel back on, noticed some side-to-side play in it.  The axle 
    nuts weren't loose but I snugged them up a bit and the looseness went 
    away.  The wheel still spins okay so I don't think I overtightened it.
    
    .13 asking about freewheel/cassette reminded me of this -- any
    relevance?
    
    The powertrain is Suntour something-or-other.  I bought the bike as
    a leftover model two summers ago so let's say that it was made in 
    1992.  It's a Specialized Sirrus.  Can anyone tell from this what
    sort of rear cogs it has?
    
    Thanks for the help.
    Erik
                                                         

    Axle adjustment wasn't what I was pointing at. When the bearing get dry
    you'll get a clicking noise. The source of these noises are really hard
    to track down sometimes. The noise travels through the tubes.
    
    I had a dry freewheel problem before (shouldn't get it with a cassette
    set-up) and thought it was my bb. I squited some oil into the freewheel
    and the noise went away...
    
    Chip

i doubt the noise is in the free wheel/cassette
since e notices it pedaling, the free wheel is engaged, ie not moving, probably
   not the source of noise

we still have not isolated where the noise is originating.......
is it possible to replace one of the wheels and see if the noise goes away
how about if you pick up the bike and spin the wheels independantly
'once per revolution' i am assuming referred to one rev of the wheels, not crank
does the noise happen at all speeds
rough or smooth road, or both

--roger

    when the freewheel is engaged, and you get the noise it could still
    be the problem because one of the pawls could be unengaged whilst the
    others are married.
    
    Another possibility is looseness in the rim joint (rare for this to be
    the problem, though)
    
    ed

is the ticking noise gone......
what was it?

--roger

    I've been off the bike for about two weeks.  Since I posted the
    original query about this noise, the noise pretty much went away
    so I haven't worried about it (-:  .  When it was happening, it 
    was definitely once per revolution of the wheel and it happened 
    while pedaling lightly.
    
    Thanks for the advice .. I will remember this string when (not if)
    the noise returns.  I'll be riding on Martha's Vineyard all of 
    next week so it'll probably happen then.         :-)
    
    Erik

My road bicycle has caught the dreaded 'tick disease' - ever since it had 
an encounter with a Saab.  The tick sounds like it is coming from the bottom
bracket or down tube area and it is very annoying.  Here are some observations:

    o It happens only when I pedal, and quickly fades after a couple of extra
      ticks when I stop pedaling

    o The ticks go away if I pull or push on the handlebars.

    o The ticks are audible in any gear, small or large chainring

    o Hitting a bump in the road seems to get the ticking started but it also
      starts whenever pedaling reaches 80rpm

    o Pedaling backwards does not produce ticks

    o Swapping the front wheel with another does not solve the problem

    o Cleaning/regreasing the bottom bracket does not solve the problem

    o Pushing on the water bottle cage dampens the tick sound somewhat (cage
      is on tight, no loose screws)

    o The headset is tight with no play

    o The tick does not have a definite pattern

    o The front forks (the left fork struck the Saab) appear not bent 
      (riding no-hands is stable)
    
My hypothesis is that something is vibrating somewhere in the frame and
a resonance amplifies the sound.

Any other suggestions ?  I am letting a 2nd bike shop look at this next
week.

    Kinda sounds like one of my aluminum Trek 1200's with a very old
    (and flexible) frame.  It gives a tick (hell, a crescendo of groans)
    as the BB is moved from one side to the other.  If I stop pedaling
    (or pedal very lightly), it stops tho; doesn't fade.
    
    Does this happen to be a very hi mileage aluminum bike?
    Kratz

	check the frame very carefully for a cracked weld or joint. i was
	riding with a tandem that had a similar problem, turns out the 
	frame had cracked near one of the rear drop outs.

garry

I would second the idea to check for cracks.  You may not be able to visually
see it.  What I would suggest is using fluorescent dye penetrant and an
ultraviolet light to make any cracks show up.  The only down side is the stuff
is fluorescent yellow.  I don't know what is would do with your paint.

Jim

    Are your pedal bearings loose?  
    
    Double check the crank arm bolts.
    
    steve

    The frame is 4130 chromoly and visual inspection shows no cracks.  A
    bike shop will be looking at it on Wednesday.  We will probably rule
    out components by swapping parts.  I will mention the flourescent dye.
    Maybe I should stop by the ER and have the frame X-rayed. ;)

>>    Maybe I should stop by the ER and have the frame X-rayed. ;)

The dye penetrant should pick up a crack better than an x-ray (yes, I saw the
;-) ). X-rays need to be in the right orientation to see the crack.  The dye
penetrant is as thin as alcohol so it easily goes into the crack.  You wash the
excess off the bike, then let is sit for an hour or two to let the penetrant
come out of the crack and spread.  Using a UV light, you get a bright yellow
fluorescent line where the crack is located.  We used to use x-ray and dye
penetrant to inspect cast orthopedic implants in one of my previous jobs.  The
x-ray gave us a permanent record that the piece was inspected for cracks, but
the dye penetrant did the real work of finding them. 

Jim 

there are place where you can have metal parts magna-fluxed (sp?)
which is special type X-Ray specifically designed to detect
fractures/cracks. this is expensive, but not too bad.

Chip

    The tick sound has vanished after I pulled off the seat post and shook
    the frame upside down.  Some of those invisible alpha particles must
    have fallen out. ;*)