I tried mustache bars a couple of times on different bikes and could never get comfortable with them as they were too wide for my shoulders, and led to hand and wrist pain when used offroad. Unlike Tom [MENTION=152773]noglider[/MENTION], I did find the 'over the ends of the brake levers' comfortable as I stretched out in a position sort of like aerobars, just wider, but I couldn't spend time enough there to justify putting up with the other drawbacks. Note that I think the secret to making such a position tenable is that you have the have the levers point straight ahead so that there's enough area available to grip... lever shape matters too.

Like [MENTION=100027]calamarichris[/MENTION] I have experimented with a variety of bars, and I do have one bike set up with some very narrow old cruiser/3-speed bars installed upside-down, and those work well for me because they're a perfect match for my narrow shoulder width. I still prefer drop bars for almost everything, but on a commuting bike where I want to be semi-upright they're just the thing - plus I can still use the ends of my brake levers (I use STI levers mounted horizontally) as aero bars when riding into a headwind.

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