Hi all.
I've been off my road bike for at least 12 years. When I was in my mid 20s and svelte it fit perfectly, now somehow my center have gravity has shifted toward the belly a little (considerably) and something must be done.

I've done a couple short <15 mi rides and at first I felt like way too much of my weight was on my bars. To try to correct I dropped my seat a little and slid it forward a little. I feel like my weight is distributed a little better, but 2/3 into my ride tonight my back really started bothering me. I don't really know where to go from here. Shorter stem? Seat down and forward more?

Any suggestions would be really appreciated.

Seat should be at a best height for pedaling, the way you reduce the weight off your hands is increase the setback

your seat moves back that shifts C of G .. weight onto your backside .

perhaps Higher bars closer to you too.. less Reach .. sitting more upright.

Move saddle back, not forward. Leave your bars alone for now. Adjust your saddle height so that, with your heel on the pedal, your knee is completely locked out with no pressure on the pedal and your hips not rocking.

And give it some time. Ride the bike. It'll take a while to get used to it again, say 1000 miles.

Thanks for the advice guys, seems counter-intuitive to my backwards reasoning. I'll throw an allen key in my bag and see if I can do better.

I found an absurdly high-end local shop, maybe I'll stop in and harass them a bit too.