I have my bars trimmed down to 700mm wide, and I use inner bar ends set around 39cm apart which is should width for me. Narrower grips are much more comfortable as Stefan says but where I disagree with Stefan is that there is no one size fits all approach to being comfortable on the bike - it is impossible to say that everyone would be most comfortable with everything in the stock configuration, there is a reason that everything is adjustable and why everything is available in different sizes. You can either experiment to find what works for you, or go to a fitter. But don't keep suffering keeping everything as is - if you're not comfortable then something needs to change.
Wait what? How dare anyone question Stefan (i.e. a self taught bike fitter)...what is the world turning into
Stefan is right in that you put more weight on your butt when you raise the bars...no question there, simple physics. It doesnt mean you shouldnt try different things. If you are having pain in your hands/shoulders you should address that first.
I have always tried to have my bars as low as possible to facilitate front end traction. There was a time my bar height was 2 inches lower than my seat height. It has slowly crept up over the years as I get older with more weight, less core strength and more accumulated injuries. These days my bars are 1/2 higher than my seat (as recommended by a fitter using a guru bike fit system)
I went to the fitter to address hip pain issues. I put in about 6k miles a year. Hip pain was getting to the point that I wasnt sure what would happen when I commited weight to my hip when getting out of bed in the morning and thought my cycling days were done. I have been using the method of seat height adjustment where you make sure you heel just grazes the pedal in its lowest position. I have been doing this since the early 90s. As it turns out this was way too high as I was rotating my hip when doing this adjustment causing excessive seat height. There was a point were I did my own video analysis and subsequently lowered my seat height by a full inch. The pain was better but not perfect.
My bike fitting was just over 2 hours and $250. While we focused just on seat height (ended up lowering it 10mm, moving it forward 10mm). Its amazing to feel the difference as tiny adjustments are made while you are actually riding and putting down power. At the end of all that we played with handlebar height(bar started out even with seat) and as he raised the bar height 10mm it felt like he had decreased the pedaling resistance. It was actually quite a big difference. Most hip pain is gone these days despite a pretty bad mtb crash on my hip which left me in crutches for a month (couldnt put full weight thru hip)
From that fitting we determined, I would likely be better off with the saddle being even more forward than what i could achieve on that bike so I built up a new frame with steeper seat tube. Any steering lost by raising the front end (less weight on front) was negating by moving my seat position forward on the bike. Another thing was that due to my body dimensions, I would actually benefit from a wider q-factor than I have on my BBSHD setup.
Sorry for the long winded description not related to handlebar height but it demonstrates how complicated bike fitting can be.
Before the fitting, I was also experiencing pain/numbness n the hands after 1/2 hour or so but fought lowering the bars. I went thru about 5 handlebar setups with different heights/backsweeps. I also went thru about 15 different grips.
The simple facts are:
Handlebar height determines how much weight is on you hands and butt and overall front end grip.
Grips and backsweeps control how that weight is distributed thru your hands
Simply raising the bar height 10mm has fixed my hand pain/numbness issues. Yes there is more weight on my butt...so what, life is full of compromises
I could have saved alot of time/money and pain by just going to a bike fitter first.