Ride in front! My BF is faster than me (without EVER training, argh), although not a ton faster - he would probably average 17-18 mph, I average more like 15. I almost always ride in front, because we've found I go a lot faster that way. It must be psychological - when I'm following, I guess I get lazy, or perhaps resentful, and tend to drop back. When I'm in front I push a lot harder. I guess the sight of open road is more inspiring to me than the sight of BF's back end.

If he just can't contain himself enough to ride a little slower, well . . . perhaps it's time to let go of the dream of riding together. You can still tinker and shop for gear together!