I know Thomson do one but are there any other options? also are there any disadvantages with running a layback ?

The Thomson one is ugly

In theory they are weaker

There are loads of options – in fact more than in-line I would say

What about offset rather than a lay back?

i.e. 20mm Ritchey one:

very very few complete bikes come with an inline post. most have an offset like the ritchey above – the thomson post is just an ugly play on that without the ability to put the saddle right down !

people do get visually confused though and think that setback posts are inline because they dont have the bend in the shaft !

What about offset rather than a lay back

Same thing.

Ive always assumed frames are designed to take layback/offset seatposts to get the correct fore/aft relationship to the cranks. This has certainly been the case with all the frames I've owned. In-line posts throw the seat too far forward and are more driven by fashion than function!

Layback/setback will..

1. Increase the distance from the saddle to the handlebars (good if your bike is cramped, bad if it is too long already)
2. Shift your weight backwards (can make the bike more likely to wheelie from seated, which can be a pain on climbs if pronounced, and potentially gives more rear wheel traction when seated)
3. Change where your hips are relative to the pedals, i.e. you will be pedalling slightly more 'behind' the pedals as opposed to 'on top of' the pedals.

It's usually good to stick to whatever the bike manufacturer stuck on there at least to start with, and only change if you are having problems (e.g with reach). Sometimes people suggest that needing to change from/to layback/inline means your frame is the wrong size. Not me though…

In-line posts throw the seat too far forward and are more driven by fashion!

I was unaware of this fashion! Inline is the new black?

I doubt many bike companies design their bikes to use layback posts.

I doubt many bike companies design their bikes to use layback posts.

Really?

Well the traditional way to adjust fore/aft seat position is to drop a vertical line from the boney protrusion below the knee so it intersects the pedal axle with the cranks at the three fifteen position.
Most complete bikes seem to be fitted with layback posts in my experience.

KOPS: http://www.sheldonbrown.com/kops.html

my bikes an orange crush 17 " I've got an 18 " five which is perfect for reach. the crush is the perfect size height wise ( I've got an inch and a half before the maximum insertion line ) but I feel like I'm going to fall off over the front sometimes, the stem is only 55 mm BTW

err KINGTUT – Offset is not the same as layback IMHO 🙂

Offset is a setback clamp and a layback has a kink in the tube with an inline clamp no?

No talkin' cr@p agin – google is your friend – just Thomson always calls theirs a layback and most others a setback – I stand corrected 😉

I doubt many bike companies design their bikes to use layback posts.

if i was a vindictive man id go looking for something from epic fail to link to here … but im a lazy man so its ok 😉

Do Thomson laybacks REALLY only offer 16mm of setback?

http://www.lhthomson.com/elite_sizes.asp

The richey above, and some FSA's offer 20mm setback but I would have thought
the Thomson gave much more than just 16mm? ❓

I would be interested to know that aswell enfht

Can some one explain the "Thomson is ugly" thing. I just don't get it. Is it just because of the set in the tube and not at the clamp ?

I use a Thomson layback, the wrong way round!
Don't give a toss what other people think. It works for me…

"I would have thought the Thomson gave much more than just 16mm?"

Nope, it's 16mm!

I used to have one of the layback Thompson posts on my Epic and while it worked well it did look nasty. I replaced it with an offset EC70 which was lighter, looked better and still gave the same riding position.

I've got one of the offset Ritchey WCS posts on another bike and it's also a nice bit of kit, as are the Easton posts.

so something like the richley post would give more layback than the Thomson ?

Anyone know the post with the most layback?

IIRC Thomson comes in 2 layback sizes:

10 degree (16mm setback) or 7 degree (11mm)?

Surely the bigger the layback either the heavier it is or the weaker is is?

confused as the Thomson looks like it would give more layback then say the richley in the pic above

just seen a stylo race seatposts 25mm offset on chain reaction which looks ideal anyone used one of these ?

Agreed – I measured my Thomson layback as giving about 16-17mm.

I like to position my saddle back a long way and have found I-Beam Seatposts great for this.

what's the setback on the Ibeam posts ?

iBeams have capacity for a lot or layback – up to 40mm i think

Having said I-Beam seatpost have lots of layback i have measured it and discovered i was talking rubbish !

Setup 1 – Thompson Layback post fitted with an SDG Bel Air Saddle slid back on the rails as far as it would go.

Setup 2 – SDG I-Beam micro post fitted with a Formula FX saddle set back as far as it will go

The Thompson setup actually increases the cockpit size by about 5mm.

This surprised me as i know that i feel further back on the I-Beam setup. I think this is because the Bel Air has a pronounced lip at the back of the saddle whereas the Formula does not. Thus i can sit further back on the Formula saddle in comfort

Looking closely at the I-Beam post / saddle combo i can see that the post is an inline design and all the layback comes from the saddle.

So to conclude. If you want sit as far back as possible the best bet might be a different brand of post with 25mm layback ( richey , easton ? ) coupled with a saddle with a flat rear ( Fizik Gobi , SDG Formula FXR ? )