I do not recommend carbon rails for a MTB saddle , YMMV .
I have to say i am not too worried about breaking the rails. I dont ride downhill sitting down with my feet off the pedals too muchI rode a carbon railed Bontrager saddle 13 years ago. A rail eventually broke at the edge of the seat post clamp. Granted, this was 13 years ago, but has carbon really progressed that much when it comes to a saddle rail? Nothing but aluminum since with no failures.
I rode a Flite saddle left over from road days for a few years, until I rode a WTB saddle that had stitching on it - helped hold my butt in place while climbing. I really dig my WTB saddle, it just feels right. The Flite is a good saddle though. If you are set on a Flite no matter what, considering the in and out of the saddle action with mountain biking, comfort wont be a problem. You will be able to slide off the back for technical descents with no problem also. Climbing function will be the issue that makes it or breaks it. If you are buying it from your LBS, they should have a trade in policy if you don't like it.
At the time mine broke I only weighed 155 - but then the bike was a ti hard tail. It was at a mountain bike race and I was planning to camp and ride the next day. Fortunately, with all the folks at the race I was able to borrow a saddle from someone who was heading home. On examining the rail, it had been failing a bit at a time. The other rail showed signs of failure also, though it had not yet broken, so it was not due to a sudden impact or singular event. As I said earlier, wear/failure was right at the edge of the clamp.Sheepo5669 said:I have to say i am not too worried about breaking the rails. I dont ride downhill sitting down with my feet off the pedals too muchSeriously though, I think it would be okay for my application.