Miles2go

Just moments after ordering a saddle at a friend's bike shop, I was talking to him as he lifted a 15lb CF road bike to clamp into the stand, holding the back of the saddle and stem as he lifted it. As the bike got up to about shoulder level the saddle just ripped off in his hand. I immediately said "That saddle I just ordered doesn't have carbon rails does it?" Both rails failed right where they were clamped. It was pretty impressive.

jmX

There's a ton of clamps that aren't compatible with CF rails. That may have been the issue.

vespoli

Or they were way over torqued. Don't condemn an idea based on one example. Your experience is hardly controlled.

Miles2go

The setup looked pretty much like a newer factory build. The seat clamps were a good 2" long at the rail contact/clamp area. I didn't pay much attention to model clamp this was but could gather that info come Monday. I'm not worried; I don't ride on carbon rails.

Sprocket Man

If the bike weighed only 15 lbs, it seems odd that it failed when he picked up the bike by the seat. If anything, I'd think that the rails would have failed when he installed the seat and rode it around, because that would have put a lot more pressure on the seat and rails. Of course, he might have just installed it and hadn't ridden it with the new seat.

Nick Bain

was it a Chinese seat?

Aurelius

QUOTE=Nick Bain;12966353]was it a Chinese seat?[/QUOTE]

I have two "Chinese" carbon/carbon rail saddles (Merek off of the bay). I weigh 220lbs and have'nt had a single problem. Fantastic, super light, comfortable and cheap. About 1K KMs on each and no probs what-so-ever. IF one breaks I will definitely buy again with no hesitation.
The one that broke must have been a cheap American Knock-off of a Chinese one.[

Miles2go

That's if and when you could ride again. This thing had an instant catastrophic failure and if that happened out on one of the local descents, it would have been beyond hard to stay upright. The saddle is the same brand I ordered just a few minutes before, a Fizik and the bike was in for a tuneup. Anyone tuned in with a smaller (53cm-ish) black/black Dogma 2 that's in being tuned up?

Reynolds 

Maybe they're engineered to stand a lot of downward force but not the opposite way? But what do I know, I have a superstitious fear of carbon stems, saddle rails, etc...

danvuquoc

Likewise I have a chinese carbon/carbon rail 90 gram saddle from ebay, its very comfortable and firm. I have 5,000 miles on mine -- no issue whatsoever -- I'm 158 lbs though.

cyclebycle13

In my 4 years of carbon saddle use, my first one failed when the rails "pretzeled"- used the wrong type of seatpost w/ it (halfpipe cradle and beams). But, not catastrophic- they replaced that one w/ a brand new one and after slightly over 2 years, the rails failed- but again not catastrophic- the material started splintering. I was on a century ride and I noticed my saddle leaning back. That said, I was able to shift my weight forward on the saddle and alternate w/ standing and finish the last 35-40 miles of the ride w/out incident.

No catastrophic failure. Now using an ax-lightness saddle.

datlas 

I have two "Chinese" carbon/carbon rail saddles (Merek off of the bay). I weigh 220lbs and have'nt had a single problem. Fantastic, super light, comfortable and cheap. About 1K KMs on each and no probs what-so-ever. IF one breaks I will definitely buy again with no hesitation.
The one that broke must have been a cheap American Knock-off of a Chinese one.[[/QUOTE]

I also have a Merek saddle with no problems.

Certainly one should be careful with carbon anything, but I would not damn all carbon-railed saddles based on one failure.

clx1

I have Fizik carbon railed saddles on two bikes both of which have covered many thousands of miles. Something was clearly wrong with the saddle/clamp/fixing arrangement in the OP example.

StanSeven

Yeah, either the clamp wasn't the correct one or it was over-tightened or both. CF rails are strong when you follow instructions