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What's the purpose? If saddle rails slide fore and aft- wouldn't this be just better? Call me a bonehead....I'm still new to biking!
 

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A layback post also works well for the rider 'in between' frame sizes.
My Prophet is an XL with a layback Thompson post...I wish they made 2XL.
 

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velocityrob said:
A layback post also works well for the rider 'in between' frame sizes.
My Prophet is an XL with a layback Thompson post...I wish they made 2XL.
You'd think, but normally it'taint true.

Most frames are built with identical seat tube angles throughout their size range. Notice that the Seat Tube Angle of 75° covers all four frame sizes.

Since riders typically adjust thier saddle position (height, fore/aft) relative to crank position, it wouldn't really matter if you rode a Small frame with 18" of seatpost showing, or a XL frame with 13" of post sticking up -- they'd all put your but in the same place.

Any changes made with greater setback on the Small frame would be exactly the same as any changes made on the XL frame.

The seat tube angle of the Prophet is fairly steep, so it's likely most riders would want a healthy amount of setback to get into a into a familiar riding position.

 

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The layback post & longer stem make the cockpit longer as well. Both change where the center of gravity is and the layback post changes the angle of attack on the cranks.
 

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When I had my med Prophet fitted for me because of my knees, they (shameless plug http://www.svcyclingcenter.com/) put on a set back seatpost (Thomson elite) and moved the saddle back a lot. I'm 6 ft, with a 32 in inseam. I can ride much further now with no knee problems.
 

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I'm noticing that when I'm climbing I'm slightly pushing myself off the back of the seat. I seem to adjust myself forward on the saddle to be comfortable. I've rotated the new Easton CNT handlebars forward a little to see if this will help. I already have the seat adjusted as far back as possible. If the handlebars don't help, should I get a Thomson layback seatpost?
 

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Why do you adjust the seat as far back as possible if you adjust yourself forward on the seat? Shouldn't you move the seat the opposite direction?

Layback seatpost would move you back and that is not desirable in this case.

When I climb a steep hill I sit on the tip of the seat. It moves my body mass forward and helps climbing.

Yes, that trick with your handlebars will work too. You can also get a longer stem.
 

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ozvena said:
Why do you adjust the seat as far back as possible if you adjust yourself forward on the seat? Shouldn't you move the seat the opposite direction?

Layback seatpost would move you back and that is not desirable in this case.

When I climb a steep hill I sit on the tip of the seat. It moves my body mass forward and helps climbing.

Yes, that trick with your handlebars will work too. You can also get a longer stem.
The seat is as far back as possible and yet when climbing, I'm sliding off the back of the seat. That means the seat is still a hair in front of where I need it. I just want to know if I'm missing any other adjustments before I buy parts.
 

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Oh ok...I got it now....All you need is to change the seat angle. Make it so the back is raised tiny bit and the front is dropped a tiny bit. Let us know if that helps.

There is no setup that would work ideally for both descends and ascends. You need to make compromises.
 
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