Another idea, rather than mess with finding and swapping stems is adding MTB bar ends to the handlebars.
I love mine. They extend forward so you get the extended reach you are seeking, the forward leaning position that is more aero.
I really love mine and don't care to ride my MTB without them. More aero on the road if I ride it on flats. NOT TO MENTION, better on climbing as you can lean forward and pull back for more torque and leverage.
I like the hand position it adds as well. Riding the bar ends on my MTB feels much like riding the hoods on my road bike.
I RARELY RIDE MY MTB ON THE HANDLEBARS BECAUSE THE BAR ENDS ARE SO MUCH MORE COMFORTABLE AND EFFICIENT.
Bar ends can be rather inexpensive and easy to install. 😎🙂😎
You can see the bar end sticking up by my hand on the handlebars.
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Another view. You set the angle which gives you the reach you desire extending the ride position across the bike.
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This day I rode on the paved bike trail 40 miles. Comfortable and plenty of aero position to move along at a decent speed.
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Great for climbing, adding leverage to the ride position. This is a 10% grade and I appreciate the extra leverage on these kinds of grades.
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Different styles, angles, lengths, shapes depending on what you want and care to spend and how cool you want to look. 😄 I have little short stubs on my MTB. Paid about $20 at Performance back when they were still around.
There are even longer versions that will give you even more reach, if you do a search.
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