Hi!

I recently finished building a bike that I love, but that upon completion I realized I had set up just a bit too long for me, and was finishing my rides with significant upper back pain. Ive currently got a 10 cm nitto dirtdrop stem, and I decided to fix the problem with a 5 cm nitto techmonic. However, once the techmonic arrived I realized by holding it up next to the current stem that while it will move the bars backward about an inch and a quarter, it will also drop them about an inch and a quarter lower, from just above the saddle height to just below it. This feels a bit like creating a new problem to solve my first problem. Does anyone have any alternative stem suggestions? Or should i just accept the lower/closer trade-off? I already have my seat shoved as far forward as it will go without turning the set-back post around backward.

Thanks!

A 5 CM stem? Sounds like you need a frame with a shorter top tube. Sliding the seat forward to decrease reach can cause problems.

Frame sounds like it's at least two sizes too big.

So to clarify, the significant back issues were when I had the seat shoved all the way back. Today I completed a 50 mile ride with the seat forward (at about the midpoint of where it would be on a non-setback post) and had only mild discomfort. I estimate that at current bar height I need to lose just 1 or 2 cm to be fully comfortable.

Geometry is cruel. If you have a short high angle stem and you make it shorter it gets lower, as you found out.
You can get steering tube extensions that just move things up, and then use a short 0 degree stem.

Check this website out. It makes it easy to find a stem that will meet your needs.