Richie Sachs wrote:
>
(cut)
> ya' know what i think the real issue is? some people don't
> have balls. they don't know how to go down a hill without freezing
> up. period. i MEAN, do you ever here of guys descending in
> the pyrenees, in the pro ranks, on factory built bicycles...do you
> ever hear about these guys losing it at 62mph? no! because they
> have honed their bicycle handling skills. for the rest of us, when
> it comes to the issue of shimmy, and descending speeds, and the
> related issues, i say it's all pilot error.
I agree. The first time it happens it scares you to death! But all it takes to stop the shimmy is your knee against the top tube. I have seen riders totally freaked and almost go off the road and down the side of a mountain the first time it happens.
If someone doesn't clue them in that all bikes will shimmy if their natural vibrating frequency is initiated by a shiver, being too tense hitting a small rock in the road etc. their opinion is that they have a "killer" bike. Then they start looking at the headset, wheel construction, etc.; all the wrong things. They even sell the bike and bad mouth the builder!
Sometimes the frequency of the frame is beyond the speed you ride, sometimes not. My '60 Mercian Superlight road/track bike will start to slowly shimmy if I ride no hands at 15 mph. All I have to do is lean forward and it stops.
Ride smoothly and relax on those hair raising descents and you'll be fine. And be ready to put that knee against the top tube if you can't relax...
Chuck "if I was any more relaxed I'd be asleep" Schmidt SoPas, SoCal