carleton

I'm not really tuned into the bike industry from the POV of the manufacturers.

Bike components seem to be pretty mature. The systems are, for the most part, interchangeable (stems, bars, saddles, etc...). I know, for example, that you can't mix/match campy and shimano shifting systems, but you can remove a Campy system and replace it with Shimano.

So, why the move to proprietary seatposts? As a heavy guy that has had several proprietary posts slip/tilt during training and racing, they simply don't work as well as the standard 27.2 posts. I won't even consider buying a frame that doesn't use 27.2.

I guess that there are some aero benefits. But those benefits do not outweigh the drama caused when the post has slipping/tilting issues or needs to be replaced.

27.2 posts, like the reference Thomsons, have an amazing track record. Also, if you break a 27.2 post, you just go down to your local shop and buy another.

So, can someone explain why bike manufacturers insist on creating their own custom (and often inferior) seatposts?

mike868y

why is this in the racing subforum?

carleton

Because I am a racer and this affects my racing.

1nterceptor

I test rode a 2014 Cannondale HiMod Synapse with a
25.4 SL-K carbon seatpost. I thought it was ok, and I
guess C'dale thought that post is lighter than a 27.2.

Happy Thanksgiving!

carleton

What about the non-round shaped posts? Those cause the most issues that I've seen (even from 170lb guys). The posts will slip into the frame.

Also, the 1-bolt seat clamp systems that allow for minute adjustments, but are prone to tilting when "on the rivet". The 2-bolt systems don't tilt.

This is an example:



vs




Is it a game of ounces where they choose these posts because they use less metal hardware?

Ygduf

that thompson post is way lighter than the specialized post, for whatever it's worth.

my foil has an aero-shaped proprietary post. all the non-round posts have more slipping problems because nothing clamps as well as the round tube with a round clamp. aero posts are front/back or just the sides clamped. area of pressure is decreased.

misterwaterfall

I broke the seat post clamp on my Fuji the day before s stage race and had to make a new nut/bolt set up by hand sense I couldn't find a clamp locally. Pain in the ass, all in the name or aero

mattm

Cough, 41, cough.

carleton

Yeah, I replaced my stock Specialized post on my Tarmac with a Thomson.

EVERY frame that I have owned that used a non-round seatpost had some slipping issues. At least 5 frames, including a few ultra-high end track "sprinter" frames. Every Single One.

carleton

This isn't a "41" topic because of stories like this:

It's one thing to have seatpost issues in group ride. It's another to have a seatpost fail during a race.

Ygduf

damnit, I'm bored. Working on a campus on the day before Thanksgiving where 95% of the students are away!

I don't even know what this thread is for, but imma comment anyway!!

mattm

Technically, that story was about a failure the day before the race. =]

Honestly I bet you'd get more answers about this in the 41.. anyway, carry on.

misterwaterfall

What if I'm in the drops doing SST dirty 30 over unders at 90% FTP while my seat post slips on my way to the race?

bigfred 

System Integration?

Grabbing a larger share of the total build cost/profit?

Increased vertical integration?

Already employed engineers trying to justify their continued salaries by "Overthinking" yet another bicycle component?

The UCI not letting the aforementioned engineers utilize their skills and talent on parts of the bicycle where it would really make a performance improvement?

Our collective resistance to integrated seatmasts that limit resale value once cut?

So, we get aero seatposts between our undulating thighs, in what is quite probably the dirtiest air around the entire bicycle,... That slip.

carleton

EXACTLY!

Also, do you think that regular consumers simply aren't supporting (by buying) the manufacturers that are making solid frame/components that use standard dimensions? Or is it that, they are buying the hype about competitive the advantages of this or that minor thing being a big advantage, thus forcing the manufacturers to fake innovation in order to win the A vs B decisions by the consumers in the local shops? i.e.:

Bike A has a normal aluminum seatpost.
Bike B has a Carbon Aero seatpost.

I wonder how bike manufacturers got into this annual cycle of "innovation". Imagine being an engineer and being forced to innovate designs of a 200 year old, relatively simple machine...every year. It's this kind of thinking why we have razors with 5 blades and pizzas with cheese in the crusts.

RPK79

I was with you until the pizza comment. Cheese in the crust was a stroke of genius.

carleton

"You know pizza that has cheese in the crust? That was Frank's idea. He bought a second house on the beach with the bonus he got for that. Freakin genius."

bigfred 

Ans: C. All of the above.

No matter how many times you, me or anyone else posts the graphs showing that the rider accounts for over 90% of the total drag and the wheels, and especially the front wheel, account for the vast majority of the remaining 10%, and that the seatpost is ultimately going to account for some infinitesimally small portion of the remaining fraction.

We still see deep aero sections and go,...."ahhhh" as if the Girl from Ipanema just walked by.


They call it, "responding to market demand." They're doing it "for us", not because of us. Supposedly;-)

Not infrequently some of those "innovations" are simply marketing for the results of the greater pressure placed on those engineers to produce a more easily and cost effectively produced product, than to actually pursue any performance gains that are best very mariginal.

1. Performance gains from frame and component advancements are very limited and at best marginal. There was a pretty good article a couple years ago about GB Cyclings objective and quantifiable examination of potential performance influencers. Rider genetics, training, health (including mental), fitness and nutrition were the biggest determinent by far. The only reasons we saw resources trickle down to the component level were apparently: 1. Politics (moving some money in the right direction) and 2. An excess of funding that would allow such.

2. There was also an article a few years ago by a former bicycle engineer or marketing guy who took the then latest and greatest Specialized TT frame and all it's supposed "advancements" apart. Item by item he went through and explained how changes were made to minimize the number of molds required, reduce defect rates by making parts easier to mold, etc. and then how those changes were "sold" by the marketing department to us cyclists as "advancements".

I wouldn't want to be a bicycle engineer. I love the sport to much to do that.

How much extra weight and engineering cost is there to the stems and cranks of Time's latest and greatest "integrated" frame systems in order for them to sell "one size fits most" solutions at halo price points?

carleton

Thanks for the insight!

bigfred 

After I posted that, one thing came to mind that can't be overlooked at the really high end of the game. And, that is mental state. For some athletes it's just as important to "think" that no stone has been left unturned and that they have every possible advantage in order to perform up to their potential. Regardless of whether some of those concerns actually provide a measurable improvement or not.

So, with that in mind, maybe dealing with increased cost and weight, decreased replacement options and slipping is a small price to pay for the very reall advantage that placebo can provide:-)

tetonrider

specialized rarely (i say 'rarely' but no examples come to mind) designs a part to be the lightest weight.

skinnier posts usually flex a bit more, so that helps with perceived comfort on stiffer frames. posts with a bit of offset also help in that regard.

i am a fan of thomson posts, too, but compared to some other posts (particularly the thomson w/o setback) the ride is a bit more harsh.

that specialized post you show was designed to further reduce vibration. (in my experience they succeed at that...but i've still sold every specialized round post i've had -- they are SO heavy for what they do.)

i've spoken with some specialized engineers as to why they often have "heavy" posts on even $10k bikes (their s-works epic comes to mind). it's weird, but it does come down to hitting a price-point, and that is an area where they can save a bit of cost and minimally effect the performance of the bike.

bigfred 

The seatposts weren't a comment on weight, but, on the development and inclussion of a feature (the single point anchor bolt) when a superior system already existed that doesn't suffer from an issue that the new system creates (lack of anglular stability when riding the rivet).

tetonrider

i got it...but then you concluded with a question wondering if decisions are about weight.

i am bolt-agnostic; i currently have a few bikes with 1-bolt posts and a few with 2-bolt setups. all else equal, a 1-bolt setup IS lighter. i find them a bit touchier to set up because multiple things can change at once, but i generally don't have a problem with the angle changing while riding if torqued properly. could be a function of my weight and riding style, though.

furiousferret

My Speed Concept had its seat post fall in the middle of the race (Sprint Triathlon). It went down about an inch, I thought, 'I can deal with this', then it dropped all the way. They replaced the clamp (which 1.0 had this issue with all bikes) but it still drops about a quarter inch every week or so.

tetonrider

damn. not familiar with this post, but i assume it is carbon. do you use assembly paste? i find it helps quite a bit.