Bought a cheapo carbon saddle from the bay just for teh lolz & to have as much carbon componentry as poss. on my XC bike – have just “discovered” oval rails :/

What to do? I assume all carbon saddles have these kinda rails? So, should I be looking for a seatpost to match or might converters be available? I also got a nice second hand (cheapish) Next SL seatpost for it to go on, but it doesn’t…

I can’t help but I’m interested to know what the problem is. I thought the rails were ovalised for strength but still fitted a normal clamp so long as it clamps the top and bottom of the rails rather than the sides?

What Rubber says sounds about right, at least I hope so as I have a nice new Fizik on order…

Not all seat post clamps will take the larger rails – some need a different clamp; Bontrager spring to mind.

can’t think why a Next SL wouldn’t work though…

@rob Hilton

Many carbon saddles use ovalised rails for strength, but you end up with a larger clamping cross section, typically 7 x 9 mm, whereas round section cromo rails typically are 7 x 7 mm

As long as your seat post can accommodate the larger section it will work, try the seat post manufacture’s website should list the info.

My S-Works seatpost came with 2 top clamps:

1 for Alloy rails & 1 for 7 x 9mm carbon rails.

can’t think why a Next SL wouldn’t work though

With a newer one it wouldn’t be an issue, as they clamp top & bottom, but the older ones have side clamps – kind of a square peg in round hole situation.

I thought the rails were ovalised for strength but still fitted a normal clamp so long as it clamps the top and bottom of the rails rather than the sides?

Yep, this is the issue. I can clearly see the shape of the rails won’t mate with the clamps, so I’ll have to get rid of the seatpost and scour the classifieds/ebay for a suitable replacement…