Are you saying pad stack was 37mm above hx, which was 600, giving you a pad stack of 637? Not sure what that number is tracking...
Pad Stack for a 54cm P5-6 w/ 30mm of spacers and the high V is 655mm, w/ 40mm of spacers it's 665mm. I'll assume since you said you felt like you could stretch out more the pads were all the way forward, giving you a reach of 460mm to back of pad.
So, with a Pad Stack of 655mm and pad reach of 460mm, yes you are a little upright as you said.
I would not put you on a 54cm P5d. You'd be in the upper right quadrant of the fit range, with barely any room to get longer. On the 56cm P5d, you'd be in the upper center of the range and would have room to adjust. The EX10 mono-riser would add reach to this equation, and also allow native tilt.
For the P3x, again you are in the upper right quadrant of a size M, but square in the center of the range for a size L.
Make sense? 56cm P5d or size L P3x.
I've just sold my size 54 P5 Six and I'm looking at either the P5 disc, P3X or even the P series depending on what would fit best.
I always felt comfortable in general but did feel too high at the front and felt like I could stretch out a bit more.
The bike was fitted with the higher aduro fitting and 30 or 40 mm of spacers under the base bar.
I did have a guru fitting which is below, hopefully you will be able to determine what size would be good for myself, either 54 or 56?
I also ride an S5 with 10mm of spacers and a 130 stem
Saddle Height to BB 791mm
Saddle Setback to BB 19mm
Drop from saddle to Bars 140mm
Reach from saddle to Bars 780mm
Bar Length 250mm
Pad stack 37mm
Crank Length 170mm
Saddle thickness 53mm
Saddle Clamp to nose 129mm
My Height is 178cm and my inseam is 83cm
Eric Reid AeroFit
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