Hello, I would like to put a carrier on my Turbo Creo Expert. I see that there is a special clamp for the seatpost with two nuts to screw the carrier, but I cannot find the appropriate measure. The normal clamp has a diameter of 30.8 mm and on Specialized's page I only find 29.8, 31.6, 31.8, 32.6 and 34.9 mm.
Why don't you ask your dealer? Or just use a caliper and measure the seat tube yourself?
About carbon parts on bicycles: My experiences are not that long yet, just three years on my first gravel bike and one year on the Creo. But today I totally trust in frames and forks of serious/well-known brands/producers for a sportive bike. I've seen tests of destroying alloy and carbon frames from "neutral" brands (which offer both) and the carbon frame won. And I've seen several alloy frames failing in real live. Maybe I would not choose a carbon frame for my ride allday to the railway station and to the grocery store. And I would not choose a carbon frame from a very cheap brand or shop.
But I was always a little bit afraid of carbon at stem, handle bar or seat post, also as I'm a heavy rider. But carbon is on it's way here as well and for example at race or gravel bikes a carbon seat post is quite normal (also on my ones). But I would take more care of life time/aging here.
Where I'm dissapointed at the moment from carbon is for wheels/rims. Fine for competitons, but for allday use quite sensible, at least for gravel/MTB use. I have two good and quite expensive carbon wheel sets with well-known rim brands for my gravel bikes. On both the rims had quite ugly scratches already after a few hundred miles. No crashes or unexpected contacts with rocks or anything else, no jumps, just normal gravel use on unpaved, sometimes rough roads. Especially the rim on the front wheel seems very exposed. One has a scratch so deep, that I'm not sure if it's still safe to use. On the other hand I had in my life dozens of alloy wheels/rims used for many years and thousands of miles and never any marks like this. I'm thinking of going back to alloy rims for gravel after these wheel sets.
But back to frames: I sold the gravel bike with that ugly front rim scratch a few weeks before (without the carbon wheels) and inspected the frame and it's bottom side very carefully before selling it. I expected quite some marks due to the rim and as the frame had a lot more miles than the wheels. I found absolutely nothing, after 2.5 years. After cleaning the frame it looked everywhere as new.
I'm not sure why there is such a big difference between carbon frame and carbon rims here. The lower tubes and the area around the bottom bracket is also very exposed to dirt, sand, rocks, stones. Is it the surface finish/the painted colour or just these few thin transparent plastic covers/not much more than tape in these areas? Can't they make the rims the same way?