Tom,
Generally "soft" or "hard" rims refer to the hardness of the alloy
they are made of. Older rims are generally soft and not heat treated
or hard anodized. More modern rims are frequently better alloys and
can be heat treated to improve strength.
The other factor on rims are the wall thickness and/or profile of the
extrustion; both of which can effect the strength of the rim. Rims are
a combination of all of these factors. One can choose what kind of
performance they need from their rims based on an understanding of
these factors. Needless to say, the number of spokes in the wheel will
also have some effect on the overall strength of the finished wheel,
along with a few other things like amount of dish and so on.
Brian Baylis
La Mesa, CA
We often speak of a rim being strong. Some are held to be stronger
than others. Has it ever really been spelled out just what we mean by this? Obviously if a rim bow ties easily, it is not strong, but I have never
had a rim failure of any kind and I am no light weight rider. When we speak
of " soft" in regards to a rim, what are we really saying? How can we
separate this aspect of rim performance from their spoking? Has Sheldon or some other agency ever done any objective or scientific testing of on topic
rims (Or even those rims many of us often use on on topic bikes, like Mavic
Open Pros, MA2s or Module Es ~Module Es are on topic...right?~) for
qualities like strength or softness and posted the results so that we might objectively assess them? Tom Sanders Sitting on his stash of Module Es and MA2 &3 rims, but riding mostly
Open
Pro,
In Lansing, Mi USA