Originally Posted by smashndash

I’ll pitch in. But I’ll also add what I learned from hindsight.

1) 3 pairs of shoes - one size 45, one 43 and one 41 (OUCH) before getting a 42 wide. Turns out I have wide feet and none of the bike shops I went to even thought to figure that out. Still haven’t found the perfect shoe because my forefoot has very little volume and my heel is narrow, but I’m able to ride without ending up in tears after 20 minutes.

2) pirelli p zero velo tires. I was using these on my skinny rims before. I never felt quite confident leaning hard but they were OK for the most part. With phat rims, I felt like I could barely turn. Leaning at close to 50mph was a hair-raising experience. Turns out that the tread on p zeros is very narrow, and the coefficient of friction on the sidewall is (obviously) much lower. Cornering when 30% of your contact patch is slick is no fun. So now I will only buy tires that have a wide usable tread cap.

3) I bought 170mm cranks because a fitter told me he “would not recommend” 165s. I’m 5’ 7” and wear 31” jeans (long legs). Within a couple months, I said screw it and bought 165s anyway. Easily my best biking-related decision yet, besides the shoes. Maybe it’s placebo, but spinning, climbing, getting aero are all easier now. I learned that, despite what everyone seems to think, shorter cranks will not kill your power, ruin your sprint or make it harder to climb out of the saddle, assuming you stay reasonable. Now I have this 170mm crank just sitting here.

I have more but I think these are the big ones.