New Mk3 Mercury

[alexmac]

Yes I'm using it as supplied with the plastic shim. I might try the foil and/or grippy compound suggested above because I do find the p

My Mercury came a metal seatpost shim.

The bikes are so different that the spacings are totally different. I am at 'limit nose down' with the adjustment on the supplied Thorn seat post which actually feels like it should be about right but I would like the option to experiment by dropping the nose a bit more. I can't do that without buying a new post though since I don't have any spares knocking about.

The thought of having the saddle significantly away from the horizontal horrifies me. Why so nose-down? I would see this as a sign that the handlebars should be higher. If flipping the ahead stem doesn't raise the bars enough then other stems with more angle are available and relatively inexpensive.

My mistake, mine is actually metal too but just looks like black plastic.

Re the saddle, I prefer having the nose modestly down because I find it comfortable but on this frame and seat post 'maximum nose-down' is not radically off horizontal (see e.g. photo +5 above).

[JohnR]

My mistake, mine is actually metal too but just looks like black plastic.

Re the saddle, I prefer having the nose modestly down because I find it comfortable but on this frame and seat post 'maximum nose-down' is not radically off horizontal (see e.g. photo +5 above).

So it's probably the same shim and same batches of seat post and frame as I've got. I would suggest putting some layers of aluminium foil between the seat tube and shim.

If the bike has a different geometry then your body position and hence sit bone spacing will be different which would change the optimum saddle width (more upright = wider, more head-down = narrower).