Making the jump from the road bike to TT bike. Problem is that I am a tweener. I am barely 5’10 and size between a 54 and 56 cm frame according to most manufacturer sites. I am slightly longer in the torso.
Would it make sense for me to go with the 56 cm b/c of the longer top tube length or should I listen to the inseam measurement which says I am a 54?
Go get a fit. You’ll be better able to tell what bikes will work for you and will be less likely to have to make adjustments that can affect the bike’s handling.
Because they’re what I’m most familiar with, here’s a comparison of the M Shiv and the new P2 in a 54:
Shiv: reach 405, stack 540, head tube 139, frame set $2950
P2: reach 411, stack 522, head tube 114, frame set $2800
So, the P2 is lower, longer, will let you get lower, and is slightly less expensive. If your assessment of a long torso is accurate, the P2 may be a better fit.
Full disclosure: I’m 6 ft and overall average, but have short femurs. I’m on a large Shiv.
x3 on the fit recommendation… a 54 from one may be very close to a 56 from another, a medium from a 3rd, large from a 4th and so on… general fit based on a generic size denomination without any real meaning doesn’t really make for a good fit recommendation…