I wouldn’t rotate the stem around, but I don’t think it would cause serious problems if you did except putting the bars way to close to you.

I would stick with the adjustable stem and get some new bars that have more rise and also swept back more. Even something like a cruiser bar if you want to get that upright. You may have to lengthen a cable or two.

Here is a fun mountain bike I ride once in a while that I cloned with a cruiser. Very upright, great for drinking coffee and riding.



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