In article <ydMQe.2342$UI.992@okepread05>,
"Sotos" <
[email protected]> wrote:
> <[email protected]> wrote in message
> news:[email protected]...
> > http://www.cyclingnews.com/photos/2005/vuelta05/index.php?id=vuelta052/2_14g
> >
> > I saw old Mike Norton (of BOB, not young Mike Norton of YSG-Ideal Tile)
> > do this too.
> >
> > JT
> >
>
> Would someone be so kind as to explain exactly what part broke? I can't
> seem to figure out what type of failure would have led to the right side of
> the crankset being all caddywampus such as it appears.
Shimano's got some 'splainin to do. This is one of their new (well, 3
years or so now) crank designs where the crank spindle is permanently
attached to the right (spider-side) crank, and the left crank is held on
using two pinch bolts and fine splines.
This seems to be either a failure of the pinch bolts (could even be
mechanic error if that is the cause) or a broken spindle. If the spindle
broke, it would have to be right at the crank end, because we can't see
any broken bit of spindle still attached to the left crank, and this
photo gives us perfect position to see such.
So my best guess is that the pinch bolts failed, either due to
overtightening, undertightening, or some failure of the parts (either
bolt or crank. But a spindle failure is possible.
Apologies for the PDF, but this is a good diagram of the assembly:
http://tinyurl.com/7ssz9
http://bike.shimano.com/media/cycling/techdocs/en/bikecomponents/FC/EV-FC
-7800-2251_v2_m56577569830565939.pdf
Share & Enjoy,
--
Ryan Cousineau
[email protected] http://www.wiredcola.com/
"I don't want kids who are thinking about going into mathematics
to think that they have to take drugs to succeed." -Paul Erdos
