How much difference does seatpost offset make?

silverpigeon Posts: 327
edited September 2010 in Road buying advice
I ordered a seatpost with standard 25mm offset. LBS ordered one with 45mm. It's the second time they've got the order wrong so I'm thinking I'll just put up with it rather wait another week

It feels OK and a quick ride up the road seems comfortable enough though I know I need to go on a proper ride to be sure. If I do that though I can't ask the shop to change it.

So how much difference will the extra 20mm make - my other two bikes have 20 and 25mm.

Will I notice the difference, are there any advantages/disadvantges to more offset?
Basso Astra
Principia Ellipse SX
Kinesis Racelight 4S
Kinesis Crosslight Pro Disc


  • If you're used to a particlar setup & you do lots of miles, changing the setback by 20mm in one jump can lead to injuries...

    I would return the seat post and demand the one you ordered. It's a fit issue after all.
    Others can chime in and tell you about more or less offset.

    But my opinion is that all of the plethora of offsets & stem lengths available now is to make up for an inccorectly sized frame... you can basically get 'fit' to practically anything.

    It will affect your reach to the bars, power due to the possibly altered pedalling style, and a whole host of other things...
  • moonshine
    moonshine Posts: 1,021
    If you have space to move your saddle on the rails by 20mm to offset the extra layback, it won't make any difference, but if you know where your saddle should be, you may not have enough scope of travel on the saddle rails to accommodate the difference,

    In that case, what the above poster said
  • moonshine
    moonshine Posts: 1,021
    Oh.. If you have fitted it, then it may be too late to return it as it will be marked...