So I’ve currently got a C’Dale R5000 roadbike that is 58cm. Honestly, I think it’s a bit tall for me (32-33" inseam). I was considering buying a Trek 56cm frame but my buddy who is 6’2" with a 34" inseam rides a 62cm Trek whcih seems huge to me. Do Trek’s run small? Can anyone comment on Trek road bike sizing?
Thanks
.
.
I am 5’10 and ride a 56 Trek road bike. It fits great. Does that help you?
Yes, it does help. Do you feel like you’re reaching the upper end of the fit or could someone an inch or two taller make out ok?
Guess what I really need to know is how a 56cm C’dale compares to a 56cm Trek?
I could ride a 58 Trek, but I’m afraid the top tube might be too long. I do wish that the head tube was taller. Unfortunately, I have no experience with Cannondale.
Depends on how you measure. A 56cm Trek is lower than a 56 cm cannondale, but they are about the same in terms of toptube length. Trek measures from centre to top of the seat collar, Cannondale measures to the top of the top tube.
I have owned both C-Dale and Trek. In the C-dale I would ride a 58 and the Trek Madone series a 60. Trek measures its frames center to top so a 60 is more like a large 58 c to c frame. To compare bikes, if the seat tube angle is the same, look at top tube length and head tube length.
So I’ve currently got a C’Dale R5000 roadbike that is 58cm. Honestly, I think it’s a bit tall for me (32-33" inseam). I was considering buying a Trek 56cm frame but my buddy who is 6’2" with a 34" inseam rides a 62cm Trek whcih seems huge to me. Do Trek’s run small? Can anyone comment on Trek road bike sizing?
Thanks
.
.
I have created a chart comparing these bikes. Have used same stem and spacers so you can get a feel for what the differences are and used a set saddle height to show the change in drop. Overall stack and reach are the vertical and horizontal distances of the centre of the bar from the BB, drop is from the top of the saddle to the top of the bar (the saddle height is from the ground and varies because of the differences in BB drop).
Clearly a trek is going to require a lot of spacers to get to the same height as the cannondale for the same reach. If you give me the exact setup of the cannondale I can work out what would be required to any bike.
And on the personal bias side of things - how could you leave a cannondale for a trek?? 
Sweet chart. Thanks!
As for your question…one word…CARBON.
If I’m swapping out frames I might as well go for the smooth ride.