There are few things more unsettling than the idea of catastrophic part failure on a bicycle. In that realm, broken cranks, stems, bars and especially forks are the true sweat-inducing considerations. Everything else, you sort of think you could work through - I’ve had rims crack, chainstays break, frames come apart at the bottom bracket, high speed front wheel flats… all reasonably adrenalin-inducing moments.
But, if that fork snaps off, you will be looking up before you know what hit you.
So, it’s with a fair amount of chagrin that I note this article (first cited by j. hirsch on the iBob list):
Velonews Article
Steered wrong? Racers concerned about broken carbon steerer tubes
by Zack Vestal
June 17, 2010
A
small but concentrated group of mid-Atlantic road racers have recently
broken the carbon steerers on their 2010 Trek Madone 6-Series bikes.
While the regional nature of the reports is probably a coincidence,
there does appear to be a pattern indicating that incorrect stem
installation — and even stem choice — could lead to catastrophic
failure. And at least one racer whose fork broke mid-race is convinced
that the 6-Series Madone steerers are prone to breakage even when all
of Trek’s instructions are followed.
Trek says installation and compatibility problems are at fault and
notes that the same concerns apply to carbon steerers from other
manufacturers. The company is working with the Consumer Product Safety
Commission on a consumer alert, and has made a running change to add
material to 6-Series Madone steerers.
In recent years, the CPSC has announced recalls of carbon road or
‘cross forks from Giant, Salsa, Felt, Novara, Raleigh, Redline, Cervelo
and Reynolds, although it’s not clear if any of these recalls involved
steerers breaking at or below the stem, as with the recent 6-Series
Madone failures.
All owners of forks with carbon steerers should pay attention to the
concerns raised and installation instructions when installing or buying
aftermarket stems.
The cracks begin to appear
Saturday, May 15, began like any other race weekend for Washington,
D.C.,-area Category 2 road racer Bryan Vaughan. He suited up and spun
to the start line of the Poolesville Road Race on his 2010 6-Series
Madone. The race traverses a rolling 10-mile road circuit with a
1.5-mile stretch of gravel and dirt road. The Pro/1/2 field was slated
to do seven laps.
Vaughan’s bike sits on the side of the road at the Poolesville Road Race.
On lap 4, shortly after entering the dirt,Vaughan pulled up on the
bars to accelerate. He felt the handlebars come off in his hands and
crashed hard into the gravel.
(article continues - please click through here)