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Carbon-posts&bars?(6 posts)

Aug 5, 2002 6:00 AM
I see lots of posts about bars & seat posts. I also have seen people talk about failure and flex. I have not seen any posts discussing the Easton carbon bar. People comment on the harshness of these stiff compact alum frames & how a carbone post can help take the edge off. How about a carbon bar? Or any of the aero carbon seat posts, like that CORIMA ELLPISE in Colorado cyclist. Its 155 gms & very aero. Or even the Mike Boughros (spelling?) Seat post that came standard w/ the giant tcr line? I have heard that alhough it is aero, its also heavy. How heavy? Any comments on these?
I have Easton carbon bars...jtolleson
Aug 5, 2002 6:08 AM
and they are a spiffy gimmick. Feather light, super stiff. I'm not convinced they take anything off the road, though.
aero posts not so good...jimsawino
Aug 5, 2002 6:21 AM
recent wind tunnel tests have shown that aero posts are, in fact, less aero than a standard seatpost. i'm not sure why, exactly, but i've read it in a few different bike sources, all credible. it may sound strange, and like it goes against the laws of physics, but so does a bumble-bee flying. i think the use alien carbon post weighs 130 grams, but that doesn't include the required shim, so it may be a bit misleading.
alien carbonweiwentg
Aug 5, 2002 5:48 PM
when used on a road bike, the shim is not necessary (this according to USE). on an MTB, you'd better have the shim, though.
plan on getting your saddle position set up right the first time. that clamp is a nightmare.
re: Carbon-posts&bars?Rusty Coggs
Aug 5, 2002 6:22 AM
I got a CF seatpost on a traditional frame.Looks trick.Does not seem to do anything cheaper aluminum did not do as well.Slick finish makes it more difficult to keep from slipping.
re: Corima and other seat postsDMoore
Aug 5, 2002 9:58 AM
I had a Corima post some years back, when they first became available. The narrow, rectangular post is adapted to a seat tube by two plastic inserts.

My main impressions of the post were (1) it was difficult to get it tight enough to hold its adjustment. I had to grease the bolt, sand the carbon face where the bolt contacted it, and then tighten it down to the point I was afraid the bolt would break; and (2) the post itself is so narrow that the saddle would sway side-to-side noticeably when pedalling. It never broke, and it probably added a small degree of "suspension," but it worried me to the extent that I eventually got rid of the darned thing.

I replaced it with a WR Compositi carbon post. Huge improvement! The WR isn't "aero" but it's easier to adjust, holds its adjustment, feels much more secure, and is lighter to boot.

I also have a Burroughs post, but never bothered to install it. I didn't weigh it on a scale, but by holding it in one hand and a carbon Easton seat post in the other hand, it feels like the Burroughs weighs twice at much.

I have a Specialized E-5 for my race bike - a compact, Al frame with an Easton carbon post. It rides just fine. No basis of comparison, though, as it's the only post I've had in that bike.

On other bikes, steel, Ti and Al but with conventional geometry (no sloping top tube) I've had the full gamut of seat posts - Al, carbon, and Ti. On those frames, there was NO difference in feel among the various materials. Whether or not it makes a difference with more post exposed, I don't know.