i wouldnt doubt that im not the first person to think of this.
if a seatpost was square wouldn’t that eliminate the twisting of seats on hard turns? why arent there square seatposts?
probaly would wiegh more or somthing
I can see a seat post clamp problem with square seat posts in the vertical direction. It seems round posts would clamp more securely than square with standard clamping methods. How about a round splined seatpost option?
I like the splined seat post idea, though I expect it would be very expensive.
I know a guy whole built an entire unicycle from scratch, made his own frame, had a square seatpost. You can’t use a clamp, so he had a bolt, with different holes in the seatpost. Much like the schwinn style seatposts. (only square)
The obvious problem with the bolt-style seat post holder is that sometimes a minute adjustment makes all the difference, which is not possible with a bolt-through post.
Getting a good frame (like a KH), a good seatpost (like a Thomson), and a good seatpost clamp will pretty much eliminate any problems with the seatpost twisting. You don’t need to go square, you just need to go quality.
I can see some problems with trying to remove a square seatpost after it has been in the frame for a while. If you don’t grease the seatpost before you put it in you can get oxidation that will cause the seatpost to get stuck in the frame and be difficult to remove. You need to twist the seatpost to break the oxidation and free the seatpost. That would be impossible with a square seatpost. I see future problems with stuck square seatposts.
A round post is lighter - for a given thickness of metal, the round seat post will weigh less for a given diameter.
A square seat post will not behave consistently when forces are exerted on it from different directions. There is the diagonal direction, and the orthoganol direction, and then all the vectors in between - and some forces would tend to cause twisting.
The seat clamp works by friction between metal surfaces. The friction on a round tube in a round clamp is more likely to be fairly evenly spread out.
could you not just use up and down forse to remove the rust
eg hit it with a hammer
Ive seat post like this it was round with a grove down the front, I hope you know what i mean with this hagered picture:o
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/ /
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Edit: that turned out teribble :o
I kinda get what you mean, so its still round but it has a notch down one side to keep it from twisting? that is a good idea…I think it would make the seatpost weaker though. but just for riding around it would work/
Circles tend to be a strong shape because they distribute force along a consistantly changing surface, rather than around corners. I would suspect a square seatpost would be more subject to bending than a round one.
Exactly, I can’t remember where I’ve seen it before so I don’t know if it is actuly in existance or I just thought it up 
on my pogo strick and thing they use rounded poles with little pins that come out in to holes doown the side of the outer seat post if you know what i mean
speaking of splined seat posts… why dont they make splined pedals… seems lieka good idea to me
Chase
Not sure why you’d need splined pedals. The thread orientation seems to work fine as long as you have the pedals mounted on the correct side.