Hi Guys,

First post, so here it goes. I bought a used bike and had to turn the stem around to a less aggressive posture since the position was straining my neck and back. Since I adjusted the stem, the handlebars have been kind of jerky/stiff. They are biased in certain directions, mainly straight ahead. I read somewhere that this problem can arise from distorting the fork tube, did I do that somehow? I'm not quite sure what I did wrong, I just flipped the stem around. Any help would be much appreciated. TIA!

Sounds like an indexed headset(search)- can happen as the headset ages. I doubt you distorted the steerer tube, though I guess it is technically possible. Could also be a too-tightly adjusted headset. I'm not touching the whole backwards stem can of worms.

Turning the stem backwards seems like a really really bad idea. Post some pics!

The binding issue you are describing might be due to cable lengths for your shifters and brake levers. I don't imagine you cut new cable housing and stuff did you?

The guy that sold me the bike told me that if I didn't like the aggressive position the stem put me in, I could turn it upside down...so I kind of just trusted him on that. I didn't do anything to the cables. I removed the stem and had a friend hold onto the handlebars, turned the stem upside down and put it back together. After that I started having this problem. I didn't cut or remove anything...the most I could have done was stretch the cables a bit, but I doubt that happened and/or did anything. Here are some pics....don't mind the tape. Wasn't me.

https://img716.imageshack.us/i/img2594.png/

https://img830.imageshack.us/i/img2596.png/

https://img85.imageshack.us/i/img2599.png/

Oh, you flipped it up. When you say flipped around, I personally thought that you actually rotated the stem backwards so that the handlebars were over the top tube (I can't imagine how that would be stable).

You can bind the headset too tightly (or loosely) and cause poor handling. I had poor handling and I didn't know what was causing it until I had a mechanic open things up, and the bearings were rolling around in the head tube because the rings had broken in 3+ places. That might not be your problem, but I'd have a mechanic look at it if you don't know if you have overbound the headset or not.

Sounds like you didn't set the bearing pre-load when you put the stem back on.
Try these instructions.
https://www.parktool.com/repair/readhowto.asp?id=65