Originally Posted by
mack_turtle
Yikes! I set my bike in the trainer and tried to just start again with a 90mm stem and a 70mm stem, both pointed upright with the drops in the angle I found works by feel. then I put my hoods at an angle on the bar that felt good—pointed slightly up. with the 70mm stem, that angle at my shoulder is way less than 90° with my hands on the hoods. I need to drop the stem lower or use a longer stem to get it there. it's very upright and that's what feels comfortable to me at first, but it feels cramped at the same time. I tried it with some compact Sora shifters, my Hylex levers, and the two stems. the closest I got the the 90° mark was with the longer stem and the Hylex levers. so by conventional fitting methods, the longer stem and full length brake levers are "correct."
from a fit standpoint, why is that 90° angle important? in what situations should I go shallower or steeper? my goal for this bike is to be able to do long rides of 50-100 miles on mixed surfaces. I believe my legs are a bit long for my overall height, as I am 174cm tall and have a 84cm inseam, which places my inseam at 48% of my overall height. this means that when I put my saddle at the correct height, it's difficult to get the handlebar high enough. I might play around with "riser-drop" like the Surly Truck Stop bar or a more upright stem. the fork is steel and has about 30mm of spacers under the stem already. this is a CX bike that has a pretty low stack height.
from a handling standpoint, what does a drop bar bike with a reach that is too short do? is there a point where it makes the bike twitchy? is there a point where it's so "stable" as to be difficult to ride in a group or some some singletrack?
I also noticed that my saddle might be a little low, and I ride with my back quite rounded. this is a whole conversation I probably need to have with a fitter, but considering the pandemic and my unsatisfactory experiences with fitters, I'll keep trying to DIY it for now. as with everything, I am well aware that my body is to blame for a lot of my limitations. I can't reach my toes to save my life and I probably have overdeveloped quads and tight hamstrings like most cyclists. I need to work on that as well. I know how, I just need to do it consistently.
If I post a video or some photos on this forum, would that be helpful?
Proper fit is all about comfort over long distances. Some think that aero is a big factor, but it's really only a small factor. Mostly comfort for butt, back, shoulders, and hands. It all works together. It's the same basic fit for road, cyclocross, gravel, and MTB. There are small differences between those fits, but not worth bothering with unless one were competing. Here's my primer on DIY bike fit:
How can I fitting my bike
Most folks find a saddle to bar drop of zero to 10 cm quite comfortable. The more drop, the better the comfort because it takes your back out of compression and puts it into flexion, much more comfortable on long rides.
The upper arm angle is important because your arm then becomes a strut, no muscles need be involved to hold it in that position. There's still triceps effort because the elbows need to be bent @15° to absorb shock, but no way to get away from that.
You can try stretching every morning - I do. This is a good basic routine which prevents most cycling back and knee injuries:
IT Band pain (during ride)
Progress in flexibility is always slow, but it happens.