I was considering ordering an all carbon saddle for my mountain bike, but first I decided to try out the feel of an all carbon saddle by modding one of my old mountain bike saddles first.
The saddle I chose was an old Fizik Aliante with ti rails:
As you can see, the cover was pretty worn and it weighed in at 250 grams.
I proceeded to peel off the leather cover and manually remove the foam padding by hand. This took a while as it was securely glued to the carbon shell. I then broke out the dremel with a soft wire brush to clean the remaining foam off the shell.
The back edges of the saddle were raised about 4 mm to provide a channel for the foam to rest in. I swapped in the sanding drum onto the dremmel and trimmed the edge flat.
Here is a picture post-mod:
As you can see I was able to shave almost 100 grams, but is it rideable?
The proof is in the pudding. I clamped it in place and hit one of our more rocky trails here in Tucson: Starr Pass. I did take along my usual mountain biking saddle (265 g Selle Italia Team) just in case the all carbon saddle was unbearable and I'd need to swap it out.
Amazingly enough, the new no-padding saddle is MORE comfortable than my usual saddle. I can feel the shell flex under me when taking hits while seated. Granted, we do ride with a very high quality chamoise in our team shorts, so padding on a saddle seems a bit redundant. After back to back days riding 12 mile loops on local trails I can now report very little soreness in my arse. Less so than normal. I do ride a hard tail as well.
Drawbacks: It ain't pretty, but I figure it's on a mountain bike so I don't mind my saddle looking a bit beat-up. I suppose I could clear-coat but why bother? The other issue I discovered is that the rear edges of the saddle are a bit sharp when behind the saddle in technical sections. I may blunt them with some foam or rubber if I decide to keep using it.