I've found there's so many variables in pacing, I could write a book about the social dynamics. Instead, I'll summarize the high points of what I've found over the years...
The TLDR version is this: Make expectations clear from the outset and if they aren't met for either party, chalk it up to experience and select a different companion for future rides. You'll both be happier if you do. If you can't ride together and converse, then see if meetups along the way or at day's end are fulfilling enough to schedule future rides together.
1) From 1978-82 (before cellphones and GPS), I led cycle-tour groups professionally and the matter of pacing differences was baked-in. The most straightforward way to deal with it was to offer and divide tours and pacing into beginner, intermediate, and advance groups so people with similar physical ability were matched. Unfortunately, people often failed to estimate their abilities objectively when representing themselves. Sometimes, we needed everyone who signed up in order to meet costs and logistical goals, resulting in wildly varied groups. In either case, each group had people whose abilities *and goals* varied. As a tour leader, I found the one as important as the other to making for a satisfying group-tour experiece.
I was the sole group leader for each ride-group and fortunately stronger and more experienced than most of the participants, so I equipped everyone with a map and clear pace/route notes and most often "led from the rear", making sure the slowest riders weren't dropped off the back, while I occasionally rode up through the group to check on those ahead before dropping back. Those at the front were instructed to stop and wait for me if a turn seemed at all unclear. Regular, mandatory marked stops ensured the group bunched together at intervals. These stops usually featured some sort of interest point, activity, restaurant, or tourist destination where those who arrived early could become engaged enough to still be there when the stragglers arrived. These periodic meetups allowed for group sharing after the fact and provided a measure of bonding that wasn't possible on the road. "Mechanicals" (i.e. drivetrain adjustments, punctures) would sometimes enhance or torpedo these meetups, but holding to the rule that none could advance from a stop till all had arrived equalized things.
I adapted this "ride apart and meetup periodically" strategy when riding with mixed groups of friends who simply were unable to match pace to each other. It wwell sometimes with only a single companion of we were agreeable on th eplan from the start.
2a) On personal *day* rides, I found the best route to ongoing companionship while riding with a friend was to make expectations clear at the beginning this would be a "conversational/companionable/social" ride; that set out the need for compromise from the beginning. I found it easy to adapt my riding style (usually downward) in favor of camaraderie and sharing. If others couldn't or wouldn't, then future rides together were a no-go unless we mutually agreed in advance it would be an "individual ride together" where each would be on the same route, meeting-up only at pre-arranged stops or the end.
2b) As an aside, I've found riding a tandem can be a great pace equalizer that allows for ready conversation. Both parties arrive and depart at the same time and no one gets dropped. The more fit rider can beat themselves to a pulp and in doing so, makes things easier for the less fit. It can work well provided both riders accept the compromise of being yoked together and are well-versed in coordinating elements like mounting/dismounting and the nonverbal communication that comes through the timing chain.
3) *Touring* together with another person over an extended period of time is like a marriage for the duration of the time together. Some people just aren't compatible and trial separations or divorce are in order. For that reason, one ground rule I made for touring with anyone else on a single bike was to each be fully equipped so a break could be easily made if necessary. The catalyzing element in "breakups" always came down to terrain, weather, and personality more than differences in pacing that only get worse over time. Once the "resentment threshold" is crossed, the bar lowers by the day and remaining even-tempered can itself be enraging to those who aren't, leading to a complete loss of detente. For me, a good attitude has always been the most essential tool in my kit and I take adversity -- even over extended periods -- with equanimity. Not everyone does and people who don't will often lash out at the only person close to hand -- their touring companion.
This last element eventually cooked any desire to tour with someone other than like-minded family members for any extended period of time. It is no fun being the target of personal attacks because the weather turned unexpectedly bad or a hill was steeper than expected or a favorite coffee was not available at a restaurant rest stop, leading to an epic explosion and my acute embarrassment at the others' behavior toward waitstaff. I'm much better off riding solo and much happier for it and I find myself happily falling asleep in my own little tent rather than harboring homicidal thoughts in the pre-dawn hours.
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A last note: I've never had a problem touring at varied pace with family members, as everyone was happy to adjust pace and goals to match each other, usually somewhere in between but always favoring the less-fit rider or the one who wished to loiter or converse. When things go bad my family members were wired in similar ways to approach tough times with patience, determination, and a smile/shrug of the shoulders as we got on with it.
Best, Dan.
