That question has been asked under past versions of LEED, and LEED v4 provides an answer. If you're pursuing this credit, plan not only to provide bike storage and changing facilities, but also to ensure that the project is connected to a "bicycle network"—bicycle trails or lanes that connect, within three miles bicycling distance, to at least 10 diverse uses, a school of employment center, or a transit stop.
New math, new storage types
LEED v4 has rewritten the calculations used to determine the number of bike racks and changing facilities required for projects, and introduced the concepts of short- and long-term bike parking.
Short-term bicycle storage must be within 100 feet (30 meters) walking distance of any main entrance. Long-term bicycle storage must be within 100 feet (30 meters) walking distance of any functional entry. That allows LEED v4 to provide finer-tuned requirements, as follows.
Case 1: Commercial or Institutional Projects
Whereas LEED 2009 required storage for 5% of all users measured at peak periods, LEED v4 requires only 2.5% coverage with short-term bike parking, while requiring 5% coverage for regular building occupants with long-term parking. In each case, a minimum of four spaces must be provided on all projects.
Rather than requiring changing facilities for 0.5% of full-time equivalent (FTE) occupants, as in LEED 2009, LEED v4 requires one onsite shower with changing facility for the first 100 occupants (a 1% rate), and then another for each additional 150 occupants (a 0.7% rate).
Case 2: Residential Projects
Residential projects must provide short-term bicycle storage for at least 2.5% of all peak visitors, and provide long-term bicycle storage for at least 30% of all regular building occupants. There are also minimums: four short-term spaces, and one long-term space per residential unit.
This contrasts with the LEED 2009 requirement of covered storage for 15% of building occupants.
Quality of bike storage gets its due
LEED v4 requirements also address the quality of the bike storage itself.
Bicyclists know that all bike racks are not created equal. Beware of “wheel bender” bike racks and other types of bike racks that neither keep the bike supported nor secure the bike effectively. For LEED, bike racks should "reflect best practices in design and installation," according to the LEED Reference Guide.
That typically means supporting the bicycle in at least two places to keep it from falling over, and allowing the owner to lock both the bicycle frame and one or both wheels with a U-lock. The rack must be securely anchored and resistant to cutting, rusting, bending, and other deformation.
BuildingGreen offers guidance and a curated list of how to find quality bike racks.