Philcycle

I've got the chance to jump on a good deal on a 5.2 pro. But, I'm a little concearned about fit. I ride a 54 Felt F75 right now, & I'm pretty much between a 52 & 54 on the Trek, judging by frame specs. Another potential problem is I use a zero setback seatpost on the Felt to help with KOPS, but I don't think the Madone offers one yet. Do you think going with the 52 would be better for all around fit? Anyone else run into this problem? Thanks!

DaveSSS 

I see several problems. Needing a nonsetback post on top of a steep 74.5 STA would be highly unusual, in order to attain KOP. Are you sure that KOP has been measured correctly? The bike must be sitting absoultely level if a plumb bob is used. An expert like Andy Pruitt would drop the plumb line from the very front of the kneecap to the end of the crankarm.

FWIW, I choose my saddle setback based on weight balance over the saddle, not KOP and I use a 25-32mm setback seatpost with a 74.5 degree STA. Depending on the saddle brand, my saddle nose will be 6-7cm behind the center of the BB, with a 73-74cm saddle height.

On to the other issues. You haven't provided enough info to provide advice with regard to the rest of your setup. How about a saddle height, the total head tube length, with the headset and all spacers, plus your stem angle and length? Without that, there's no way to figure the stem setup on a different frame.

FWIW, the Trek 52cm has a 30mm shorter head tube and even the 54cm is 20mm shorter. The 56cm is the only size that actually has a taller head tube. From a vertical standpoint, you are in between a 54and 56cm. The same goes for the frame reach. The 56cm Trek has about the same reach as your Felt. The 54cm is about 8mm shorter in reach and the 52cm about 12mm shorter in reach.

Philcycle

Let me do some measurements when I get home, but I did find they sell different seatpost caps in different setbacks. I don't necessarily trust how my fitting was done initially, but I've messed with KOPS & the zero setback does seem to help with that. Thanks for the advice! Are you talking headtubes on the standard fit or pro fit Madone?

DaveSSS 

You posted 5.2 pro, so that's what I compared. Tha 5.2 series has a much taller head tube.

Philcycle

Ok, thanks!

Philcycle

Alright, finally.
Headtube with spacers 170mm
Saddle height - 96cm
Top of Saddle to BB - 71cm
Tip of Saddle to Center of Bars - 50cm
100mm Stem, 6 degree rise
172.5 Crank

Thanks!