79pmooney

I look at your first photo and see bars a touch lower than the saddle. Pretty high but not end of the world. Seat back a normal distance. But I also see brake hoods that are angled up a lot. I wonder if this twists your wrists up, pulling your pinkie up, pulling along the bottom of your forearm and pulling your triceps.

I wonder if you would be better off with the brake levers/hoods slide down to closer to level to relax the underside of your arm. A quick and dirty test would be to simply rotate your handlebars down and go for a ride. I would consider: first - lay a yardstick along the bottom of your handlebars and put a piece of tape where it hits the seatstay. (So you can return the rotation to the "before" later.) Loosen the bolts clamping the handlebars, rotate them and re-tighten. (Important - this must be done correctly! Research "torque", get the wrench and do it right or have a shop do it.)

Now, ride. Triceps better? If yes, measure the angle of the brake hoods with a level or protractor or marking a wall. Return the bars to their previous rotation. Un-tape the handlebar tape to below the brake hoods. Using the correct tool (perhaps a 5mm allen wrench but brake levers vary) loosen the clamp and slide the hoods down to that angle you documented. (You may need to install longer brake cables to properly reach the calipers. I'd cheat and let them poke out of the handlebar tape early until you've ridden and know this is an improvement.)

Or, do as I do. Remove all the tape. Use just enough electrical tape to get the cable housings to behave. Ride the bare handlebars carrying all the wrenches to rotate the bars, move brake hoods, maybe even move headset spacers. Make changes. Observe how you like the changes as you ride and how you feel after. Don't tape the bars until you feel comfortable.

Edit: Weight on hands is considered bad by many but isn't always. What is important is that our hand position is anatomically right when we have that weight on them. (I'm a skinny and long guy with lots of wind resistance and not a whole lot of muscle. Getting long and low is a must for me. That means either too tight a tuck at my waist for good breathing and comfort or a lot of weight on my hands. I go for the weight. But I also have to get that position right. And if I do, my hands can go further than my legs can push me. Ie, good enough!)