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Part of Bike itinerary building: how it works, step by step
How to build slack into a cycling itinerary: the parts worth your time
Where to put spare time in a cycling itinerary so a delay does not spread, and why slack has to be designed in early rather than added at the end.
Slack is the difference between a delay and a ruined trip. Most itineraries have none, because spare time is the first thing cut when a route looks appealing and the last thing anyone thinks to add back.
What to take away
- Slack has to be designed in at the start. Added at the end, it gets cut.
- Put the spare time before the fixed commitments. Delays spread forward, so slack early is worth more than slack late.
- One flexible day protects a whole week. One flexible hour protects nothing.
- A two-day trip needs two hours, placed before the return journey. A four-day trip needs a half day. A week needs one full day with nothing planned, positioned around day four.
Design it in, do not bolt it on
Federal guidance makes the same point about accessibility: accessibility is too often treated as a separate issue to be addressed after the planning process is complete.
Slack behaves identically. Decide at the start that one day of the trip carries no commitments, and it survives. Try to find that day once the lodging is booked and the shuttle is paid for, and it does not exist.
Where to put the spare time
Protects against
- Before a fixed transfer
- Missing a train or shuttle
- After the longest day
- Fatigue, weather, mechanical
- Middle of a week
- Everything downstream
- Final afternoon
- Almost nothing
Strength
- Before a fixed transfer
- High
- After the longest day
- High
- Middle of a week
- Highest
- Final afternoon
- Low
Where slack pays off most
Position
- Before a fixed transfer
- Missed train or shuttle
- After the longest day
- Fatigue, weather, mechanical
- Middle of a week
- Everything downstream
- Final afternoon
- Almost nothing
Protects against
- Before a fixed transfer
- High
- After the longest day
- High
- Middle of a week
- Highest
- Final afternoon
- Low
Strength
- Before a fixed transfer
- After the longest day
- Middle of a week
- Final afternoon
Take the Great Allegheny Passage and the C&O Canal Towpath from Pittsburgh to Washington, about 335 miles. A common plan is seven riding days. Put the empty day at Cumberland, where the passage ends and the towpath begins. If rain costs you a day earlier, the second half still runs on schedule.
How much is enough
How much slack per trip length
- 2 hourstwo-day trip, before the return journey
- Half dayfour-day trip
- One full dayweek-long trip, around day four
That is a lot less than most people expect and a lot more than most itineraries contain.
The numbers look small because slack works by being unallocated, not by being long. Two spare hours before a train cover a puncture, a wrong turn, and a long cafe queue.
The same two hours spread as twenty minutes across six days covers nothing, because delays do not arrive in twenty minute pieces. Keep it in one block, and keep the block empty.
Plan across the whole route
FHWA's metropolitan pedestrian and bicycle planning handbook is written for agencies coordinating across many jurisdictions. A traveler planning day by day makes the same error, producing five good days that do not connect.
Lay out all the days at once, then place the slack, then fill in the detail. The pacing for trail towns is in planning a trail town trip without rushing it, and the ordering method behind all of it is in how to build a bike itinerary.
