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Discussion Starter #1
I took my 2005 Roubaix to my lbs for maintenance and the first thing the owner said to me was "that seat post is dangerous." He then told me about a guy whose seat post broke when he hit a bump. It snapped at the zertz insert. So far, all I've found about this are a few comments on road bike review.com reviews of the seat. Only one person actually had one snap and other people say it was a defect on early models that's been fixed. Anyone know of a thread I've missed or have any information on this? Is it safe?
 

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Call or Email Specialized to see if there has been a recall.
 

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Discussion Starter #3
MikeBiker said:
Call or Email Specialized to see if there has been a recall.
I called Specialized and they said that there had been a small problem with some earlier models a couple or more years back. Apparently it wasn't enough of a problem that they needed a recall. In response to the problem they added more material to the seat post. They said if the post was used correctly--not for mountain biking for example--and is installed correctly--not torqued down way too tightly--the seat post should not have any problems.
 

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Carbon posts are almost always going to be more prone to breakage then metal. When you factor in user error in applying too much clamping pressure on post binder on with a work stand, then the number of breakages increase even further. IMO carbon is a great material for a ton of things but for posts and handlebars it is less then ideal. Carbon tubes have poor 'hoop' strength so they are very vulnerable to clamping pressure and/ or pivoting against a clamp; both things which posts and bars are constantly exposed to. You can definitely make carbon work for these applications but they seldom have the same stiffness/ weight/ strength ratio.

I love my Roubaix Comp. and I think it was specd. out great. However, I hated the stem, seatpost, and saddle. I lost 40 grams and gained stiffness by switching to a Thomson X2 stem; lost 40 grams and gained stiffness, ease of adjustment, and safety by switching to an Thomson Elite Setback post; and gained a ton of comfort (for me) switching the saddle out to an Arione.

There has been a bit of talk on here lately about the quality of Specialized posts, seats, etc. I think the Avatar seat was pretty nicely built, it just didn't fit me. The stem was pretty dam heavy and I didn't like the angle options, but otherwise nice enough. The seat post however sucked IMO, it was hard to adjust, heavy, and very flexy. I could feel and see the thing flexing and I just didn't trust it. The Roubaix is plenty damp enough, I don't need carbon in the seatpost or another Zertz insert.
 

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Discussion Starter #5
Boardmill said:
Carbon posts are almost always going to be more prone to breakage then metal. When you factor in user error in applying too much clamping pressure on post binder on with a work stand, then the number of breakages increase even further. IMO carbon is a great material for a ton of things but for posts and handlebars it is less then ideal. Carbon tubes have poor 'hoop' strength so they are very vulnerable to clamping pressure and/ or pivoting against a clamp; both things which posts and bars are constantly exposed to. You can definitely make carbon work for these applications but they seldom have the same stiffness/ weight/ strength ratio.

I love my Roubaix Comp. and I think it was specd. out great. However, I hated the stem, seatpost, and saddle. I lost 40 grams and gained stiffness by switching to a Thomson X2 stem; lost 40 grams and gained stiffness, ease of adjustment, and safety by switching to an Thomson Elite Setback post; and gained a ton of comfort (for me) switching the saddle out to an Arione.

There has been a bit of talk on here lately about the quality of Specialized posts, seats, etc. I think the Avatar seat was pretty nicely built, it just didn't fit me. The stem was pretty dam heavy and I didn't like the angle options, but otherwise nice enough. The seat post however sucked IMO, it was hard to adjust, heavy, and very flexy. I could feel and see the thing flexing and I just didn't trust it. The Roubaix is plenty damp enough, I don't need carbon in the seatpost or another Zertz insert.
With all the seatpost sizes Thomson makes, how do you pick the right length--probably depends on how high you need the seat? Did you get the inline or setback? How did you decide which of the two?
 

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but does an aluminium seat post mix well with a carbon seat tube?

Boardmill said:
Carbon posts are almost always going to be more prone to breakage then metal. When you factor in user error in applying too much clamping pressure on post binder on with a work stand, then the number of breakages increase even further. IMO carbon is a great material for a ton of things but for posts and handlebars it is less then ideal. Carbon tubes have poor 'hoop' strength so they are very vulnerable to clamping pressure and/ or pivoting against a clamp; both things which posts and bars are constantly exposed to. You can definitely make carbon work for these applications but they seldom have the same stiffness/ weight/ strength ratio.

I love my Roubaix Comp. and I think it was specd. out great. However, I hated the stem, seatpost, and saddle. I lost 40 grams and gained stiffness by switching to a Thomson X2 stem; lost 40 grams and gained stiffness, ease of adjustment, and safety by switching to an Thomson Elite Setback post; and gained a ton of comfort (for me) switching the saddle out to an Arione.

There has been a bit of talk on here lately about the quality of Specialized posts, seats, etc. I think the Avatar seat was pretty nicely built, it just didn't fit me. The stem was pretty dam heavy and I didn't like the angle options, but otherwise nice enough. The seat post however sucked IMO, it was hard to adjust, heavy, and very flexy. I could feel and see the thing flexing and I just didn't trust it. The Roubaix is plenty damp enough, I don't need carbon in the seatpost or another Zertz insert.
Hello

Q: does aluminium seat post present any adjustment issues when being inserted into carbon frame's seat tube? i.e. material incompatibility issues meaning hard to tighten propely, slides down easily, greasing, etc.

I doubt you would notice 80 grams or even 280 grams of extra non-rotational weight. I recall replacing my MTB pedals and brick-shoes with ~300 grams lighter road racing carbon sole shoes and pedals ~12 months ago and my performance went up perhaps 1%-2% due to that fact. That was 300 grams of rotational weight lost. Granted I am far from elite but I really think the "weight thing" is taken way too far in general road riding community. I constantly see riders with "heavy" MTB shoes and pedals go as fast (or faster) any anyone else on road bikes.

thanks
 

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Stick with the Specialized post -- there is no breakage danger, unless you break the thing tightening it (that's what a torque wrench is for), and it will ride better than an Al post.
 
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