Could you elaborate on the issues you faced when building it up?
If you don't mind me asking, how tall are you and what width bar/length of stem did you go for? Does it feel comfortable to ride, not too stretched out?
I haven't ridden it enough (no 50+ milers yet) to tell you confidently that I did the sizing right. I commented a few posts ago, but I'm 173cm / 81cm. I'm pretty certain that going with a 52 (S) was the right choice. The effective top tube length is more like a 53 anyway. I was previously riding a size 56 (hand-me-down from a friend) 27lbs 3-speed commuter bike so there's a very low bar to feeling happy with the fit of this bike. My concern was mainly that the 56 has never felt too uncomfortable so dropping two sizes might cause more problems than it's worth (don't fix what isn't broken).
I chose 420/110 as the bar/bracket length primarily because that was the measurement of my commuter bike. But, that isn't a very sound way to make the decision when you're dropping two sizes. First, I figured I should keep the bracket long (110mm+) given that the top tube (TT) is shortening. Also, since the TT is shortening, I considered narrower bars to achieve the equivalent shoulder-width position. Unfortunately, since there isn't a 400/110, the 420/110 was still my best bet.
I also got a 165mm crank arm instead of the usual 172.5mm+. I'm more of a runner than a cyclist and after hard runs my knees would be extra sensitive to the lever action of cycling. I'm hoping this works out.
As for my self-inflicted issues:
- I got the wrong size barb for my hydraulic hoses (I asked for barbs and my LBS gave me some without asking about sizing) which made insertion super difficult. Eventually, I had to replace my hoses, barbs (BH90), and olives to do it right.
- I didn't know that shift cables needed special housing even with internal cabling. After my build, I realized the rear shifting wasn't going to work right, and I had to do the cabling over.
- I bled the rear brakes incorrectly. You need to make sure the bike is rotated upwards to compensate for the bottom-bracket being the natural lowest point on the bike. That way, air bubbles can propagate upwards without hindrance.
- I bled the front brakes incorrectly so they're mushy. I need to redo it once I get more fluid. I'm not brave enough to use J&J mineral oil from the supermarket.
- I squeezed the brakes (to test the feel) after bleeding the brakes (but before adding the rotors) which gets the pistons stuck in the closed position. It's a simple fix, but for a while I thought I had made a serious error.
- It took me a while to focus on indexing the rear derailleur rather than the futile process of maxing out the H/L limit screws.
- I didn't realize that the chain will inevitably rub against the 105 front derailleur skid plates. It was clearly impossible to avoid the rubbing, but everything I had read assumed the absence of skid plates and assured me there should be no contact when adjusted correctly.
That's just off the top of my head
