Originally Posted by
shoota
Current bike: 55.5cm ETT, 100mm stem, fits fine.
Frame on the way: 56.5cm ETT
I just assumed I could get a 90mm stem to make up for the 1cm longer TT. However, I was just told that the new frame is too big for me and that I could put down more power on the size down which is 55 ETT.
So what do you guys think?
As long as you can get the same position it doesn't matter - you'll make the same power either way. In most cases either of two consecutive sizes will work fine.
If you need a very high position, the shorter head tube on small frame might preclude using enough spacers.
If you need a very low position like professional cyclists, the large frame may limit stem options due to the extreme negative rise needed.
Seat tubes get steeper on smaller frames; too steep plus short saddle rails can make it more difficult to find a seat post allowing enough setback.