Yes.

Carbon pads tend to have poor braking performance and rapid wear when used with alloy rims. They can also pick up little pieces of aluminum, which will rapidly eat through your carbon brake track when you put the carbon wheel back in.

No.

I train on aluminum wheels and race on carbon. Race day, I switch out the brake pads. I've had good experience with the blue Reynolds pads. I just use my Al training wheels as pit wheels and on the couple of occasions when I've had to use them, I just carefully check the pads when I take them out. It's never been a big deal since you're only using the "wrong pads" for a few miles. And if you're in a crit, you're only touching the brakes a few times anyway. It's not like you're grinding down a long mountain road.

My friend switched his wheels to carbon wheels from alloy and kept his old brake pads and he had some aluminum bits in the brake pad and ruined his carbon wheels. It sucks changing brake pads, but I think it is worth it.

From a carbon wheel builder I can tell you the following:

Not all carbon is equal in terms of braking and operating capability and temperatures. Carbon brake pads are not equal. They are compounds designed to run at different temps. That will produce different results on different rims because they use different resins. The vast majority of OEM manufacturers of rims will specify what pads can be used on their rims. To use other pads will eliminate their warranty - if there is one.

In general carbon is an thermal insulator. Alloy is a thermal conductor. Heat builds in carbon. Pad compounds operate at a higher temp in general than alloy.

Old school means that this results in feeling greasy brakes and quick consumption of pads when using alloy pads on carbon rims....in general. Converse - using carbon pads on alloy will generally give you "blocky" brake feeling and tendency to not really develop good stopping power. Every manufacturer, resin and compound is completely different so....YMMV.

As far as my clients go: "You must use our supplied brake pads when running these carbon wheels." That is all we really say. I also work with a metric ton of racers. Some on my wheels, many not. Almost all train on alloy rims and race on carbon. They generally hate switching back and forth. The ones that don't - their brake tracks get chewed alive on the carbon and they can't stop their alloy worth a crap.

It doesn't take long to swap pads if you have good shoes/holders. I highly recommend using the correct pad for the correct wheel. It is the only way you will get the appropriate performance out of the pads and the rims. To do otherwise is actually just lazy...but you wouldn't be alone.

There's a nice set of photo's and comments on the link on what happens to carbon rims when they overheat on a downhill.

Many users of rim brake carbon wheels. Many issues as well and I would not do carbon with rim brakes, even if it was my only wheels. Disc brakes - Yes.

https://forums.roadbikereview.com/co...-365844-7.html

Here is what happens when your brakes over heat on carbon wheels

looks like his brakes were working fine, hence the rear wheel lift

Swap out the pads. For the 5 or 10 mins it will take, it is not worth wrecking your rims over.

You also will have to adjust the brakes to each set of rims (alignment to braking surface, any toe-in you may use, etc). May as well swap out the pads, because the wear on each set may not be exactly the same, and you'll want to keep the same pads for the same wheels.