"Peter Vesel" <
[email protected]> wrote in message
news
[email protected]...
> I know of two people with the same complaint on medium size carbon fibre
> giants.
> When they approached the bike shop from where they were bought they were
> told bad luck.
> The guys refuse to ride down any sort of a steep hill now
>
> Peter
Funny thread - I had an aluminum TCR that drove me nuts for that reason, and
tried a carbon one afterwards in the hopes that it might be better since I
liked the bikes otherwise. Nope, still wobbled like crazy on straight
descents. The carbon one had a noticeably flexy head/top tube and you could
set it off just by whacking it with the butt of your hand. Most bikes will
just shiver a moment when you do that and return to stable, but that sucker
would take a while to settle down. Dangerous on a gusty day - once had to
clip out of the damned thing at about 18mph on flat ground on a really windy
day (which was when it finally got the E-Bay boot). You could stand up,
clamp your knees on the top tube, all the usual stuff, but nothing other
than slowing to a crawl would finally get it to stop once it got going. Got
rid of it and got another bike; no more problem. Too bad the Giant sucked
going downhill because it was great going up 'em.
From admittedly anecdotal experience, I've had a number of people tell me
the medium TCR's were prone to that, but I also know a few guys that swear
theirs are fine. Did take note when I read something from pro racer John
Lieswyn recently about Healthnet getting their new TCR Advanced bikes for
'05 (even lighter); I had to laugh when he said the "lively" front end took
some getting used to. No sh#*!
For what it's worth, bikes with 73-degree head angles have always been a bit
prone to shimmying under me. To many other variables to make much of that,
but in 24 years of riding I never had a bike with either steeper or slacker
head angles do it. I can remember hitting 60mph comfortably (if briefly) on
a few steep descents with an old crit bike that had a 75 degree head angle,
and I can practically take a nap on my 72-degree angled Colnago at 50. Just
a bike-rider mismatch, or maybe some range of steering trail that just
doesn't work for me. 73 degrees is damn-near ubiquitous in mid-sized frames
though, and my current racebike has the same front end geometry as the
Giant. You can feel it trying to hunt back and forth every now and then;
just pointed it out to a riding mate recently while it was doing it. I was
standing on a mild descent, cranks flat with hands on the hoods watching it
snake a little under me. But with an oversized, laterally-wide top tube, I
guess it's sufficiently stiff to keep the oscillations from going ballistic
like the Giant. Gets your attention at times, but never makes it to scary
level.
Bottom line, treat your bike like a girlfriend; if you just can't get along,
call it splitsville and get another one. You'll both be better off with a
compatible companion! ;-)
SB
