bbaka said:
Michael said:Pat said:: I do not know what's going on, and I am conjecturing. I have not heard a
lot
: about this phenomenon in the bicycle world - indeed, I haven't heard
anything
: about it - but then I am only one notch above rank amateur regarding
things
: two-wheel. This is why I asked. This wouldn't be the first time I asked
about
: something that I thought was illogical and was told "That's the way the
world
: is". Even if the ping-ring noise were a widely recognized "feechur" of
alloy
: wheels, I think it wouldn't deter most people from using alloy wheels, if
for no
: other reason than relatively little ride time is spent in grit.
You are talking to somebody who goes nuts with a click occurring somewhere
on the bike. There's no way I would put up with a constant ping sound. I
don't know what you call "grit", but here in Texas we ride frequently on
roads where the highway people put down tar and then cover it with small
rock chips. The idea is that the vehicles will press the rocks into the
surface and create a tough road. It is obnoxious to ride on (and tends to
loosen the fillings in your teeth). So, yes, I do think if thousands of
people had a ping ping sound everytime they rode their bikes, they'd go
ballistic---or at the least stop using the wheels. It hasn't happened.
Pat in TX
I understand completely; I notice "improper" sounds that my bike makes and am
super sensitive about improper sounds my car makes. I've been known to pull to
the side of interstate highways and poke around under the hood for longer
periods than passengers thought was interesting.
After additional thought on the ping-ring thingie I decided that I should
include the spokes - material; diameter; length; tension - in the equation.
While I definitely lean toward the it-ain't-a-stress-relief-the-spokes-situation
side, more to the point I believe the spokes on those alloy rims somehow aren't
damped as much as the spokes on the steel wheels.
Whatever, I'm not going to pursue getting rid of the ping-ring noise because #1
it doesn't happen often nor for very long and #2 life is too short ... there's
this problem I've got with the saddle tending to slide backward ...
Just spend some time trying to isolate it. Is it in sync with the crank,
or the wheels. Does it come on only under pressure or all the time. I
had one of those random squeaks and it took me forever to figure out it
was the left pedal, and only under pressure at a certain rotation. There
must have been one galled bearing that only took its turn once in every
20 pedal strokes or so. Changed it for now with a kids bike pedal and it
is quit again.
Some noises are really sneaky.
Bill Baka
I hear ya re: "sneaky". Last winter I was bothered by an intermittent squeek.
Came and went during a given ride but some rides were totally squeekless. One
night I happened to notice pressure against the inside of one foot, at the
ball, each time that foot reached "bottom". My rubber boot was rubbing against
the crank!
But back to the ping-ring sound... There's a smooth (well, *even* surface),
asphalt alley right beside my house, and it still has a generous layer of grit
on it from winter, so I did spend some time experimenting. I waited until there
was no traffic on the nearby street (it would mask the noise of interest) and
rolled slowly ... 2-3 MPH. The resul precipitated the idea of dangling a
microphone at axle level and recording the noise for the listening enjoyment of
RBM readers. I didn't do it but the idea is tempting!
The ping-ring noise definitely results from rolling over grit. From a standing
start, I pushed off and let gravity move me down the almost-level alley. On
clear asphalt there is no ping-ring. When tires hit grit (rocks from broken
asphalt... say, roughly 1-2 x pencil lead diameter), the ping-ring starts, and
it continues uninterrupted until I hit smooth pavement again. Also, a larger
piece of grit that gets pinched by one side of the tire tread and thrown aside
causes a distinctly louder PING and I feel the ejection at the same instant that
I hear the sound. These spokes really resonate!
Could be exacerbated by rim material/geometry. At cruising speed, on a smooth,
quiet street I clearly hear the whisper of working wheel bearings. Bearings are
new; races are pristine (as I said before, bike is 70's vintage Japanese Schwinn
but was barely used); lube is generously applied lithium grease. Bike frame is
ChroMo. I don't think the frame material has anything to do with this bike's
being ... um ... noisier than my steel wheel+frame bike because both the
ping-ring sounds and bearing whisper definitely are loudest near the wheels.