Carbon posts...worth it?

secretsam

Currently got a (Cinelli) carbon bike with a Cinelli Vai 31.6mm Alu seat post

For more comfort, would a carbon post be a worthwhile investment? I have loads of seatpost on show so would provide some 'spring' (previous bike was a CAAD8 with limited post showing, was a bit harsh :shock: )

If it's a "yes", what's a good basic carbon post?

majormantra

I doubt you'll notice much difference, especially with a cheap carbon post.

markhewitt1978

The only way you'll notice a difference is with a top of the range post, and even then more from the weight saving than anything else. You're talking £100-£150+ so not cheap.

racingcondor

I certainly noticed a difference when I went from a cheap carbon wrapped Alu post to a Deda SuperZero but that's not a cheap post (£90 on offer at the moment so not too bad considering the RRP).

The problem is that a cheap carbon post will probably wither be Alu wrapped in carbon or just so overengineered that you lose the ride benefits (but the manufacturer knows they'll have a zero failure rate no matter what abuse they get put through).

BillyMansell

Aluminium as well as carbon can be tuned to flex but as others have said such engineering doesn't come cheap.

I used to have a Thomson Masterpiece setback post that was really comfortable but they have a weight limit of ~90kgs. I now have a Syntace P6 Hi-flex carbon which is also really comfortable but costs nearly £200 although I got mine half price from bike24.net.

Little-Jim

You could use a shim and a smaller diameter post - 27.2mm dia will give you a lot of choice of posts, and the slimmer post will flex more than the larger diameter 31.6m post you currently have and hence give more comfort. Carbon or aluminium? well, as the others have said the more you pay the better engineered they are, and the more flex (in general) but it also proves the law of diminishing returns.

secretsam

Seems like a "stick" is the best option, and a large dose of MTFU!!!

Thanks all

night_porter

31.6mm seatposts and bars were brought in to be stiff and anything that is stiff will give little flex. I have changed a 31.6mm alloy post for a carbon one and guess what? It was still stiff.

+1 to Jim's suggestion of inserting a thinner post and shims to gain some flex. You only have to see how everyone raves about the 'dales comfort (Carbon or Alloy) and the fact they use 25.4mm seatposts may not be a coincidence.

secretsam

Where do you get these mythical 'shims'?? I have an old post (27.2) that I could drop in!

night_porter

One place to look would be the very secretive and mystical....wait for it....keep the secret now....google "seatpost shims 27.2 - 31.6" or just go to CRC

me-109

Tha instructions with my Scott carbon frame forbid the use of shims for posts. Don't know why, clamping forces maybe? Might be something you want to check.

keef66

Me-109 wrote:

Tha instructions with my Scott carbon frame forbid the use of shims for posts. Don't know why, clamping forces maybe? Might be something you want to check.

I too was within a whisker of ordering a shim to transfer my carbon post to the CR1-SL when I read Scott's advice to the contrary. Annoying because the cheapo 31.6 alloy post I ended up with must negate some of the shock absorbing qualities of the CR1

me-109

I did get an unbranded carbon post off the Classifieds here. It may well be Chinese but actually looks quite decent and the clamp is nicely adjustable, not stepped. Looks like a Bontrager XXX Lite Offset. Weighs 200g, compared to the 250g that the alloy one was. Not a significant amount, I know, but it is still as stiff and does actually damp out that little extra buzz. I wouldn't pay a fortune for one, but I was surprised that I could actually tell the difference with this one.

markhewitt1978

So you rate the Bontrager XXX one then? Surprised it weighs that much, as their site says it's more like 160g.

I've been looking at that one because when I got my Scott CR1 frame they basically whacked in the cheapest seat post, so it's about 300g.

iPete

Switching from the standard alu to a Deda Drittissimo on my Allez was night and day different.

luv2ride

Putting a Specialized carbon pave seatpost on my aluminium Tifosi made a big difference, but you'd hope that your carbon Cinelli frame already deals with at least some road buzz. I also decided to stick with a 31.6mm (carbon) post on my Scott CR1 after reading the 'no shims' warning sticker on the frame. When I queried this with the supplier they advised "never to use a shim in a high end carbon frame". I'd check with the Cinelli distributor (Chicken Cycles?) as a smaller dia. post would undoubtedly be more comfortable.

secretsam

hmmmm..."Shims? Nein Danke" it seems, although I might check with Chicken and co.

me-109

markhewitt1978 wrote:

So you rate the Bontrager XXX one then? Surprised it weighs that much, as their site says it's more like 160g.

I've been looking at that one because when I got my Scott CR1 frame they basically whacked in the cheapest seat post, so it's about 300g.

I only said it looks like one. I've also seen the Bontrager listed as 160g. Mine was a hundred quid cheaper so I'm not complaining.

daniel_b

I have yet to use a couple of Ritchey wcs one bold carbon posts from crc, one inline, one setback.
Iirc they were reduced a lot to around £65.

mmacavity

http://velonews.competitor.com/2012/12/ ... t_267560/2

Monty Dog

Depends a lot on the seapost IME - something like an Easton EC90 with offset is surprisingly forgiving for my 62kg whereas I have a FSA K-Force which is rock-solid. USE make a good range of shims - I have used a 27.2 post in a 31.6mm frame without issue - just make sure the shim is long enough to extend past the toptube/seattube junction which I guess is where the Scott concerns are.

mmacavity

You are using a saddle, aren't you ......?

secretsam

mmacavity wrote:

You are using a saddle, aren't you ......?

Yes. In fact I've just got a new one which is much better, so may hold off on the carbon post

dennisn

markhewitt1978 wrote:

The only way you'll notice a difference is with a top of the range post, and even then more from the weight saving than anything else. You're talking £100-£150+ so not cheap.

Just WHAT would he NOTICE from the weight savings? :roll:

markhewitt1978

The same as you would from any weight savings.

secretsam

It's not about saving weight, with my lardy ar53 sat on the bike, any weight savings are really a drop in the ocean

dennisn

markhewitt1978 wrote:

The same as you would from any weight savings.

You can NOTICE 20 or 30 grams difference in your bikes weight? :roll:

markhewitt1978

How much meets with your approval then 20g, 200g, 2kg, or it's all meaningless might as well tow a concrete block around. Although that's not a bad idea for training...

dennisn

markhewitt1978 wrote:

How much meets with your approval then 20g, 200g, 2kg, or it's all meaningless might as well tow a concrete block around. Although that's not a bad idea for training...

I admit that kind of thinking leads to you buying carbon chainrings, carbon bar end plugs, worlds lightest frame, etc. and that all those things do have a payoff. You'll improve your local race finishes from 15th to 14th.

BillyImp

Just fitted a new carbon finishing kit on my road bike. Have to say I barely notice a difference on the seat post when riding but can definitely feel the weight saving towards the rear though as my old seat post was a real hefty piece of metal. Well impressed with carbon bars/stem though, they've made a real difference where I didn't think they would, loads stiffer.

markhewitt1978

My seat post weighs about 300g which I believe for a seat post is a lot. Once (if!) I get to my target weight I'll treat myself to a lighter one