On Sunday, December 16, 2018 at 8:19:11 AM UTC-8, jbeattie wrote:
On Sunday, December 16, 2018 at 7:19:46 AM UTC-8, sms wrote:
On 12/16/2018 12:21 AM, wrote:

Are you saying that full CF rims brake as good as AL rims and don't get worse when it is wet? That is not my experience owning a set of Zipp wheels and Mavic Comete wheels. At best they brake half as good when dry and even worse when wet. I think I'm not the only one with that experience. I don't dare myself in the mountains with a full CF front wheel. They are aero wheels and I use them as such in time trials and trying to go fast on the flats. Thank god we have a lot of that here ;-)

It's not just braking ability, it's heat dissipation. The CF rims are
not going to last as long as aluminum rims mechanically, but they also
can fail more spectacularly due to heat. One CF rim brand did an
extensive test of the heat dissipation capability of different rims to
showcase their proprietary resin.
https://www.bikeradar.com/road/gear/article/alto-destroys-carbon-clinchers-in-braking-heat-test-51474/

"The issue with carbon clinchers is that rim braking generates heat,
and, when pushed to extremes, can cause the resin to soften, which can
lead to the rim bubbling or folding open. In worst-case scenarios, the
rim can fail enough that the tire can come off or the inner tube can
burst from the heat. Years ago, a few events like Levi's Gran Fondo in
California banned carbon clinchers after multiple incidents on steep,
winding descents. "

CF rim design has improved to deal with the heat issue, but they are still not optimal. It's a nice material for disc brake bikes. I don't doubt that there are some well made Chinese CF rims for reasonable prices, but I would be suspicious of a $250 complete rim-brake wheel set. IMO, the weight differential isn't that great either -- maybe 20g CF versus aluminum per rim.. Shaping is nice for aero wheels, like Lou says.

Light stuff is faster. It IS about the bike to a degree, but I have learned that one can save money and be fast on a relatively heavy bike by choosing slower riding companions. My speed has skyrocketed after choosing to ride with the sick and disabled. Today, however, I'm riding in the rain with much faster riders, and after racking my knees skiing yesterday, a bike that weighed nothing could not save me from getting dumped on the climbs. If I only had carbon rims! I would have dominated!

-- Jay Beattie.

Let us suppose that CF wheels did wear faster than AL. While my experience has been the opposite, you could STILL buy 4 wheelsets of the Chinese wheels for the cost of one set of those sold from major manufacturers here. And from the looks of it, they are all built in the same factory.

After about 500 miles on mine I have had to install new brake pads once and there appears to be no wear on the rim braking surfaces beyond being polished on the brake track.