Different saddles with diff rail lengths,and achieving the same position

stampz

Slightly stupid questions, and I suspect the answer(s) will be "it doesn't matter", however out of curiosity...

I have been running a Giant Approach saddle on all 4 of my bikes for a couple of months, but I just cannot get on with the shape at all (https://giant-bicycles.com/gb/approach-saddle) so I have swapped to a Pologo Kappa PAS (https://prologo.it/products/kappa-pas) which suits me a lot better.

However, as you can see they both have very different rail setups, to get my normal position of around 5cm setback on the Giant Saddle I had to run it pretty far forward on the second the last marker, yet on the Prologo I have to run it ALL the way back on the max setback suggested line.

I have questions around this
1) Does it matter as long as my position is the same? The saddle width and length are the same, so reach to hoods etc has remained the same as well
2) What would I have done if I needed more setback? I know you can buy a new seatpost but this is the same on ALL of my bikes, they are diff bikes and I have had to run the saddle pretty much all the way back on everyone to achieve the setback I need.
3) Is this a known thing with Prologo seats? Do they just have weird rails?

Thanks all :-)

webboo

Are the saddles the same length. If so set the nose in same position I.e same distance to back of stem. If new saddle is shorter set the back of the saddle the same distance from the stem.

First.Aspect

What do you mean when you say "position"? There is no reason to assume that the most compmforsble spot on an uncomfortable saddle is going to be the same distance from the nose as the comfortable spot on a comfortable saddle.

The height of saddles also does vary, so make sure you aren't using setback as a proxy for raising the seat post.

stampz

First.Aspect said:

What do you mean when you say "position"? There is no reason to assume that the most compmforsble spot on an uncomfortable saddle is going to be the same distance from the nose as the comfortable spot on a comfortable saddle.

The height of saddles also does vary, so make sure you aren't using setback as a proxy for raising the seat post.

Trying to set my setback from the BB the same as it was with the previous saddle, good shout on the saddle height, might need to tweak slightly

First.Aspect

stampz said:

First.Aspect said:

What do you mean when you say "position"? There is no reason to assume that the most compmforsble spot on an uncomfortable saddle is going to be the same distance from the nose as the comfortable spot on a comfortable saddle.

The height of saddles also does vary, so make sure you aren't using setback as a proxy for raising the seat post.

Trying to set my setback from the BB the same as it was with the previous saddle, good shout on the saddle height, might need to tweak slightly

Yeah but are you measuring it from the nose of the saddle, or are you more comfortable further forward on the new one?

stampz

Initially I was literally trying to replicate my fore/aft position across the two saddles as the rest of my fit feels good

pippi_langsamer-2

I tend to measure saddle setback using plumb-line from the effective "centre" of my saddles which is at ~7cm width (measured using Vernier calliper) to centre of BB. Prologo Dimension saddles.