Layback Seatposts

[crazycanuck]

My new frame/fork arrives in three weeks & am purchasing a few small bits for it. I ordered a Thomson Elite layback seatpost as I have no idea what the difference is from an inline one?? I'm willing to try it out & see what it's like.

Do you have a layback seatpost? What are your thoughts???

Three weeks isn't going to go fast enough....

[MartianDestiny]

It's a fitting issue mainly.

A setback seatpost allows you to get a seat further back (relatively), a straight post allows you to get the seat further forward (relatively), so you can get your position correct relative to the pedals.

In Thomson the setback seatposts basically get you as far back as a standard seatpost would (maybe a hair farther). Most seatposts have an offset seat clamp area; Thomson's just put that bend in the post itself. Thomson straight posts are basically perfectly straight, which is (was at the time?) sightly odd. Good for those that need the seat forward, but not those that need it set back.

Somewhere in the middle? You could probably use either (I have a setback Thomson with my seat slid forward, could probably get a straight one and have the seat slid slightly back and get the same position).

[crazycanuck]

Thanks for the explanation but i am now wondering how a layback seatpost helps in mtn biking???? Is it better for being able to get fully back behind the seat when going downhill??

I'll talk to my cool Lbs folks tomorrow about which one i ordered...

Getting a dually's very interesting but way more involved than a hardtail!

[MartianDestiny]

It doesn't "help".

There is no functional advantage. Thomson offers two types (setback and straight) simply to allow for better seat positioning.

I'm sure Thomson would argue their setback post with the bend in the post (rather than the standard offset seatclamp) is stronger and less likely to fail (and who's really to argue with them because they make an outstanding product), but their straight posts aren't about to fail either.

I guess a setback post gets your weight further back over the rear wheel, but if that also means putting you in a bad position for pedaling (position relative to pedals) then that's worthless.

[crazycanuck]

Ta!
I shall soon find out what a layback seatpost feels like & if i don't like it, I can always sell it

Tanks for the info!

[SadieKate]

Ta!
I shall soon find out what a layback seatpost feels like & if i don't like it, I can always sell it

There is no "feel" to it. The setback of a post is simply there for fit, not functionality. On the bike, you won't notice.

At just under 5'4", I use a setback Thomson on both my xsmall Racer-X and my Motolite. I had a Marin Mt Vision that was just a tad too big for me and used a straight post (until I replaced it with the better fitting Motolite).

You'll frequently see TT bikes with straight posts or a road bike set up for timetrialing by reversing a setback post to get the saddle forward.


Editing to add a link to this page where it is easy to see that most posts are setback. What is unusual about the Thomson is that instead of the setback occurring in or near the head of the post, it is an angle well below the head.

[lunacycles]

90 + percent of seatposts are "lay back." I haven't heard that term much, but it sounds like it was described to you that way. The non "lay back" variety are the exception, not the rule. For people with normal length femurs (relative to their lower legs) or non triathletes/time trialists (i.e., the vast majority of us), a "layback" (setback) seatpost is ideal and the norm. If you have freakishly short femurs (like me), a zero degree setback seatpost can be better. But I am the exception, not the rule.
The Thomson looks weird and slightly abnormal, as they put the setback into the tubing itself, by bending it. On most seatposts, that same amount of setback is achieved simply by attaching the saddle clamping zone further behind the centerline of the seatpost. Thomsons look a bit different in this regard, but functionally are the same. So....
Don't worry about it or give it much thought. It's a killer seatpost!