Hi, first time posting after reading a lot of great stuff here. I'm hoping someone can give input on my sizing conundrum. I'm looking at a used 2017 Giant TCR Advanced Pro Disc in size Large and wondering if it will work for me size-wise. Here are the facts:
(1) I'm 6 feet tall (183cm), inseam 33.8 inches (86cm), 164 lbs (74.4kg), long-ish arms.
(2) Based on a lot of research, I'm pretty sure I would order a Medium/Large if I were ordering a new one, although according to Giant's size table, I'm right on the edge between M/L and L. But I'm looking on the used market, and this one is a Large. Otherwise, it is exactly what I want (even colors) and a good price.
(3) I did test the bike, just around the guy's block, and it felt good. If anything, a bit upright (and comfy), but good. I'm crap when it comes to assessing a bike's fit by just riding for a couple minutes, so I don't put a lot of stock in this.
(4) I've read everything I can get my hands on, and my conclusion is that most people my size ride a M/L, but there are some (a minority for sure) who ride a Large. In fact, the guy who is selling it got professionally fitted and they told him to get a Large, and he is a hair shorter than I am (but a significantly thicker guy). A racer I spoke to is also 6 ft and rides a Large - with a long stem!
(5) I have an old alum TCR1 that is a Medium (there was no M/L then) that I think is roughly equivalent to an M/L now. Has a 110mm stem. I can ride well on it, but I do think there's too much weight on my hands, and my lower back sometimes hurts. (I've never been professionally fitted)
(6) I'm in my 40s and I'm reasonably fit and ride hard, but given I'm not getting any younger I don't want a super aggressive/low position. Moderately racy is enough (Merckx fit?).
This is already more than I was planning to write, so I'll stop here. Any thoughts or personal experiences are welcome, especially from those of you familiar with Giant TCRs and their weird sizing. Thanks!