How Group Riding Changes eBike Safety: Formation, Passing, Speed, and Communication

Riding an eBike alone is relatively simple from a spacing standpoint.

You choose your own speed, braking distance, road position, and line through an intersection.

The moment several riders travel together, that changes.

Now safety depends not only on what one rider does, but also on:

• How closely everyone follows
• Whether the group rides single file or two abreast
• How much faster some eBikes are than others
• How smoothly riders accelerate and brake
• Whether warnings travel through the group
• How motorists pass the entire group
• Whether every rider can see hazards ahead
• How the group handles intersections and turns

Group riding can create benefits. Riders may be easier for drivers to notice, inexperienced riders can receive support, and a compact group can sometimes be easier for motorists to pass safely than a long line.

But groups can also create new hazards.

A small braking error can travel backward through the line. A faster eBike can close a gap unexpectedly. A rider may follow the person ahead through an intersection without independently checking traffic. And a motorist passing several riders at once has to judge a much larger moving object than a single cyclist.

The safest conclusion is not that group riding is inherently safer or more dangerous.

It is that group riding changes where the safety margins are.

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The Short Answer

Group riding changes eBike safety in four major ways:

For eBike groups, the best safety practices are generally to:

• Keep speed differences small
• Ride to the least capable rider
• Avoid race-style wheel gaps
• Accelerate progressively after stops
• Slow and spread decision-making at intersections
• Use standardized hand signals and verbal calls
• Change formation according to the road rather than using one formation everywhere

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Is Group eBike Riding More Dangerous Than Riding Alone?

The research cannot currently answer that with a reliable single number.

Most crash databases record:

• Bicycle type
• Location
• Collision partner
• Injury severity
• Road conditions

But they usually do not record whether the cyclist was:

• Riding alone
• In a group
• Single file
• Two abreast
• Drafting closely
• Using an eBike among conventional bicycles

That means researchers cannot yet calculate a strong “group eBike crash rate” and compare it directly with solo riding.

Instead, group safety has to be studied through the mechanisms that change when riders travel together.

Those mechanisms are much better understood.

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1. Motorists Have to Pass a Much Larger Moving Object

One rider may occupy only a small section of road.

A group can stretch for dozens or even hundreds of feet.

That fundamentally changes overtaking.

Research consistently identifies motor-vehicle passing as an important source of perceived danger and close interactions for cyclists.

One large Australian naturalistic study recorded more than 18,000 motor-vehicle passes. Median clearance was about 5.7 feet (1.73 meters), but roughly 5.9% of passes were closer than 3.3 feet (1 meter).

Other research has also shown that minimum-passing laws do not guarantee that every driver will provide the required clearance.

For a group, the problem becomes more complicated because a driver has to judge:

• Group width
• Group length
• Oncoming traffic
• Vehicle speed
• Cyclist speed
• Available sight distance
• Whether a lane change is needed
• How long the vehicle will remain beside the riders

A group can therefore change both the geometry and psychology of an overtake.

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Single File vs. Two Abreast: Which Is Safer?

There is no universal answer.

Both formations have advantages and disadvantages.

Single File

Single-file riding makes the group narrower.

That can help on roads where there is genuinely enough room for a motor vehicle to pass with safe lateral clearance.

But it also makes the group longer.

A line of 10 riders may become a very long moving object, forcing a driver to spend more time:

• Beside the cyclists
• In an opposing lane
• Waiting for an adequate gap in traffic

There is also a behavioral concern.

A narrow single-file group may visually encourage some motorists to attempt a same-lane “squeeze pass” even when there is not enough room to do so safely.

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Two Abreast

Two-abreast riding makes the group wider.

But it can reduce the group's total length substantially.

That may make it clearer to the driver that a proper lane-change-style overtake is necessary rather than trying to squeeze past within the same lane.

Some official cycling guidance explicitly recognizes this trade-off.

For example, the UK Highway Code allows two-abreast riding and notes that it can be safer in some circumstances, particularly for larger groups.

That does not prove that two abreast causes fewer crashes in every situation.

Direct crash comparisons are lacking.

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Formation Should Be Dynamic

The best rule is not:

Always ride single file.

And it is not:

Always ride two abreast.

Instead, ask:

Which formation creates the safest passing situation here?

Single file may be appropriate when:

• The road is wide
• A motorist can pass with adequate clearance
• The group can shorten or reorganize without creating instability
• Traffic is light
• Sight distance is good

Two abreast may be appropriate when:

• The lane is too narrow for safe same-lane passing
• A proper lane change is necessary anyway
• Keeping the group shorter reduces overtaking time
• Local law permits it

On shared paths, narrow trails, or crowded infrastructure, two abreast may block other users and become inappropriate.

Formation should respond to the environment.

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2. eBikes Make Speed Differences Inside the Group More Important

One of the biggest differences between a conventional cycling group and a mixed eBike group is the possible range of speeds.

A group might include:

• Conventional bicycles
• Class 1 eBikes
• Class 2 eBikes
• Class 3 eBikes
• Cargo eBikes
• Faster speed-pedelec-style bikes
• Riders using different assist levels
• Riders of very different fitness levels

Naturalistic cycling research has found meaningful differences in average riding speed between bicycle classes.

One German study reported average trip speeds of approximately:

The study was not specifically measuring group riding, but it illustrates why mixed groups can develop different speed envelopes.

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Small Speed Differences Become Big Problems at Short Distances

Imagine two riders traveling in the same line.

The rider behind is only about 3 mph faster.

That does not sound like much.

But a 3 mph closing speed is roughly 4.4 feet per second.

If there is only a 6-foot gap between the bikes, that gap can disappear in well under two seconds if neither rider changes speed.

That is why small speed differences that are harmless on an open road can become important inside a compact group.

A faster rider may suddenly need to:

• Brake
• Move sideways
• Overtake
• Call out
• Avoid touching the wheel ahead

The tighter the group, the less time available.

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Mixed eBike Groups Should Set the Pace by the Slowest Rider

The safest group speed is usually not the speed the fastest eBike can maintain.

It should be a pace that the least capable rider can hold comfortably and predictably.

That means considering:

• Fitness
• Experience
• eBike class
• Bike weight
• Braking ability
• Cargo
• Terrain
• Comfort with traffic
• Weather
• Visibility

If weaker riders constantly have to accelerate hard to catch back up, the group becomes unstable.

A good eBike group should minimize repeated cycles of:

stretch → accelerate → close gap → brake → stretch again

That “accordion effect” can create unnecessary risk.

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3. Acceleration After Stops Can Split an eBike Group

eBikes can make it easy to accelerate strongly from traffic lights and intersections.

That is useful when riding alone.

In a group, it can create problems.

Imagine the first rider using high assistance immediately after the light turns green.

The front of the group accelerates quickly while riders at the back are still:

• Starting
• Clipping in
• Checking traffic
• Crossing the intersection
• Waiting for pedestrians
• Recovering from the previous stop

A few seconds later, the group is stretched across a large section of road.

Rear riders may then accelerate aggressively to catch up.

That creates more closing-speed events and can encourage risky behavior.

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Accelerate Progressively

Ride leaders should avoid full-power launches after:

• Traffic lights
• Stop signs
• Tight turns
• Trail crossings
• Rest stops
• Intersections

Instead, increase speed gradually until everyone is moving.

Once the group is stable, the pace can rise.

This is especially important when mixing conventional bicycles with faster eBikes.

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4. Intersections Are More Complicated for Groups

Intersections are already one of the most important risk areas for eBike riders.

Research has found that although eBike riders do not necessarily experience more traffic conflicts everywhere, intersection conflicts can be substantially more common.

Higher approach speeds are one possible contributor.

Drivers may identify an eBike as a bicycle but underestimate how quickly it will arrive.

Groups add another layer.

A driver may see the first rider clearly but fail to realize that five more riders are following closely behind.

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A Safe Gap for the Leader Is Not Automatically Safe for Everyone

This is one of the most important rules in group riding.

Suppose the lead rider reaches an intersection and decides there is enough time to cross.

The second rider may also have enough time.

The eighth rider may not.

Traffic conditions can change significantly in only a few seconds.

The entire group should therefore never treat the leader's decision as permission for everyone to proceed.

Each rider needs to make an independent traffic judgment.

That means:

• Looking for turning cars
• Checking signals
• Watching pedestrians
• Checking cross traffic
• Judging the available gap
• Being willing to let the group separate

A temporary split is safer than forcing riders through a disappearing gap.

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Never “Catch the Light”

One of the most dangerous group behaviors is when rear riders feel pressure to catch the group before a traffic light changes.

This can encourage:

• Hard acceleration
• Red-light entry
• Poor gap judgment
• Sudden lane changes
• Reduced attention to cross traffic

Ride leaders should make it clear in advance:

If the group splits at a light, the front waits.

No rider should need to take a questionable gap just to avoid being left behind.

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Regroup Before Complex Sections

If possible, regroup before:

• Major intersections
• Complicated roundabouts
• Fast roads
• Narrow bridges
• Steep descents
• Construction zones

That way, everyone enters the difficult section in a controlled formation.

Regrouping immediately after the difficult section can encourage the riders at the rear to rush through it.

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5. Close Following Reduces Reaction Time

Cyclists often ride close together because it reduces aerodynamic drag.

In racing, drafting can provide substantial efficiency benefits.

But racing-style spacing has a safety cost.

The closer riders are, the less time they have to respond if the person ahead:

• Brakes
• Swerves
• Hits a pothole
• Avoids debris
• Loses balance
• Drops a bottle
• Has a mechanical problem

Motor assistance changes this trade-off.

Most recreational eBike riders do not need extreme drafting efficiency to maintain the group's pace.

The motor already reduces the physical effort required.

That means there is often little reason for a recreational eBike group to imitate a racing peloton's wheel spacing.

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Leave More Space Than a Racing Paceline

There is no single following-distance number that works for every group.

Safe spacing depends on:

• Speed
• Brakes
• Tire grip
• Weather
• Road surface
• Rider skill
• Bike mass
• Visibility
• Whether riders are drafting intentionally

But the principle is straightforward:

Higher speed and lower rider experience should mean more space.

A casual eBike ride should prioritize reaction margin over aerodynamic efficiency.

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6. Group Braking Can Create an Accordion Effect

When the lead rider slows suddenly, every rider behind must react.

The warning travels backward through the group.

If rider 1 brakes, rider 2 reacts slightly later.

Rider 3 reacts after rider 2.

By the time the message reaches the back, the rear riders may have much less space than the front riders did.

This can lead to:

• Wheel touches
• Sudden swerves
• Rear-end bicycle collisions
• Riders leaving the road
• Low-speed pileups

The effect becomes more important when eBike weights, brakes, tires, and rider skill vary across the group.

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Announce Slowing Early

Instead of braking first and warning second:

1. Identify the need to slow.
2. Call “slowing.”
3. Ease off the motor or pedaling.
4. Brake progressively when possible.

Emergency situations will not always allow this.

But routine group slowing should be predictable.

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7. Communication Is a Safety System

A solo rider mostly communicates with drivers and pedestrians.

A group rider also has to communicate with the riders behind.

That becomes important because riders deeper in the group often cannot see:

• Potholes
• Debris
• Parked vehicles
• Traffic signals
• Pedestrians
• Sudden braking
• Turning vehicles

A strong group therefore needs a small, standardized vocabulary.

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Useful Group Riding Calls

Groups do not need dozens of commands.

A few consistent calls are better.

Examples include:

“Slowing”
Speed is decreasing.

“Stopping”
A full stop is coming.

“Car back”
A vehicle is approaching from behind.

“Hole” or “Debris”
Surface hazard ahead.

“Door”
Potential parked-car door hazard.

“Walker” or “Runner”
Pedestrian or runner ahead.

“Clear” should be used carefully.
A rider saying the road looks clear should never replace another rider's own traffic check.

The group should agree on terminology before the ride.

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Warnings Need to Be Relayed

The lead rider may call:

“Slowing!”

But the tenth rider may never hear it.

Each rider should relay important warnings backward.

That creates redundancy.

The exact wording is less important than making sure the message travels.

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Hand Signals and Verbal Calls Do Different Jobs

Hand signals are useful for:

• Turns
• Lane changes
• Moving around an obstruction
• Intentional lateral movement

Verbal calls work better for hazards that riders behind cannot see:

• Slowing
• Stopping
• Debris
• Cars approaching from behind

The safest groups use both.

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8. Lights Can Help Drivers Understand the Group

Lights are useful for solo riders, but they may become even more important in a group.

A single rear light tells a driver that a cyclist is present.

Multiple rear lights can help show that the driver is approaching a line of cyclists.

That may improve the driver's understanding of the group's size and depth, particularly at:

• Dusk
• Night
• Dawn
• Rain
• Fog
• Tree-covered roads

Research on permanent bicycle running lights has also found lower personal-injury crash incidence among riders assigned to use them.

However, the specific claim that multiple lights reduce crashes in eBike groups has not been directly established.

So treat lights as an important visibility layer, not proof that a driver will pass safely.

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Visibility Does Not Guarantee Safe Passing

One important lesson from overtaking research is that being visible and receiving adequate passing distance are different things.

Studies testing cyclist clothing and visibility aids have found that even highly visible riders can still receive dangerously close passes.

That means high-visibility clothing cannot replace:

• Safe road positioning
• Passing laws
• Driver behavior
• Infrastructure
• Formation choices

A driver may clearly see the group and still pass too closely.

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9. Electronic Communication Can Help—but It Is a Supplement

Some eBike groups use:

• Helmet intercoms
• Bluetooth communication
• Rear radar
• Brake-sensing lights
• Connected cycling devices

These may provide useful information.

For example, a rear radar could alert the last rider that a vehicle is approaching.

An intercom could allow the leader to announce a hazard quickly.

But there is currently limited direct evidence showing that these systems reduce crashes in eBike groups.

They should therefore supplement—not replace:

• Hand signals
• Verbal calls
• Shoulder checks
• Mirrors
• Lights
• Normal traffic observation

A radar warning cannot tell you that a driver will give enough space.

An intercom cannot make an unsafe intersection gap safe.

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Keep Group Communication Short

Continuous conversation can create its own distraction.

Safety messages should be:

• Short
• Clear
• Standardized
• Relevant

Group intercoms are most valuable when they reduce uncertainty.

They are less useful if they become constant background conversation during complex traffic.

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10. Do Not Let Group Pressure Change Your Judgment

Riders often behave differently in groups.

There can be pressure to:

• Keep up
• Follow the leader
• Ride faster
• Overtake
• Ignore fatigue
• Run a changing light
• Continue despite discomfort

This is particularly relevant for new eBike riders.

Electric assistance may help a less experienced rider maintain the group's cruising speed, but that does not automatically give them the same:

• Braking skill
• Cornering skill
• Traffic awareness
• Group-riding experience

The group should never interpret “can maintain the speed” as “has the same riding skill.”

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Where Should Less Experienced Riders Ride?

There is no universal position that works for every group.

But inexperienced riders should be placed where they can maintain predictable spacing without constant acceleration and braking.

Avoid placing them directly behind someone who:

• Accelerates aggressively
• Brakes suddenly
• Uses a much faster eBike
• Frequently changes line

Ride leaders should know which riders are new before the ride begins.

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11. Shared Paths Create a Different Group-Riding Problem

The safety issue on a shared path is often not motor-vehicle passing.

It is interaction with:

• Pedestrians
• Dogs
• Runners
• Children
• Slower cyclists
• Other eBikes

A large eBike group can occupy substantial width and make overtaking difficult.

On busy shared paths:

• Reduce speed
• Avoid long two-abreast formations
• Leave space for opposing users
• Give audible warning before passing
• Pass one subgroup at a time
• Avoid overtaking near blind turns
• Do not use high-speed race formations

The safest formation on an open road may not be appropriate on a multi-use trail.

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12. Speed Mismatch Also Matters When Passing Other Cyclists

A group of faster eBikes may catch conventional cyclists quickly.

That creates an overtaking problem within cycling infrastructure.

A narrow bike lane may not provide enough room for:

• Faster eBikes
• Slower cyclists
• Opposing riders
• Cargo bikes

This is why infrastructure designed only to separate bicycles from cars may still produce cyclist-to-cyclist conflicts.

Protected lanes also need enough width for riders to pass each other safely.

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13. Cargo eBikes Make Group Geometry More Complicated

Not every eBike has the same width or length.

Groups may include:

• Longtails
• Front-load cargo bikes
• Child seats
• Trailers
• Tricycles
• Wide panniers

These affect:

• Passing clearance
• Group width
• Turning radius
• Stopping distance
• Low-speed balance

A motorist's safe passing clearance should be measured from the actual outermost part of the rider, bike, cargo, or trailer—not from an imaginary standard bicycle width.

Group leaders should also avoid assuming that a cargo bike can follow the same line through narrow gaps as a standard eBike.

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A Practical eBike Group Riding Safety Checklist

Before the Ride

• Agree on the expected pace
• Set the pace for the least capable rider
• Identify inexperienced riders
• Agree on basic verbal calls
• Review hand signals
• Confirm the route
• Identify complex intersections
• Check front and rear lights
• Make sure every rider has a properly fitted helmet
• Discuss how the group will regroup after separation

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While Riding

• Maintain predictable spacing
• Avoid race-style wheel gaps unless the group is trained for them
• Accelerate gradually after stops
• Call out slowing and stopping
• Relay hazard warnings backward
• Signal before lateral movement
• Do not blindly follow the rider ahead through intersections
• Reduce speed before complex junctions
• Allow the group to split at traffic lights
• Regroup in a safe location
• Change formation according to the road
• Leave enough space for safe overtaking
• Slow around pedestrians and slower cyclists

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Single File or Two Abreast? A Practical Guide

These are riding principles rather than universal legal rules.

Local law always matters.

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The Biggest Mistakes eBike Groups Make

Riding at the Fastest Bike's Pace

This fragments the group and forces weaker riders to repeatedly catch up.

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Accelerating Hard After Every Stop

High-assist launches create unnecessary gaps and braking waves.

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Following Too Closely

Motor assistance reduces the need for extreme drafting in most recreational rides.

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Treating the Leader's Intersection Decision as Everyone's Decision

Every rider must independently confirm that the gap is still safe.

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Failing to Relay Warnings

A call that reaches only the first three riders does not protect the riders behind them.

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Using One Formation Everywhere

Single file and two abreast are tools, not identities.

Use the formation that suits the road.

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Assuming Visibility Solves Passing Risk

Lights and bright clothing help drivers detect riders.

They cannot force a driver to leave adequate space.

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Are eBike Groups Safer Because They Are More Visible?

Possibly in some situations, but the research does not justify a broad claim that group visibility makes group riding safer overall.

A larger group may be easier to notice.

But that same group can also:

• Require a longer pass
• Obstruct forward sight lines between riders
• Create close-following risk
• Amplify braking errors
• Expose several riders to one bad driver decision

Group visibility is therefore one possible benefit, not a guarantee of safety.

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Is Two-Abreast Riding Safer Than Single File?

Not universally.

Some overtaking studies have found different lateral clearance and vehicle-speed patterns depending on formation.

But the central trade-off remains:

Single file = narrower but longer.

Two abreast = wider but shorter.

Which is preferable depends on:

• Road width
• Traffic
• Sight distance
• Local law
• Group size
• Whether a safe lane-change pass is possible

There is not enough direct eBike-group crash research to claim that one formation is always safer.

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Are Faster eBikes a Problem in Mixed Groups?

They can be if the speed difference is poorly managed.

The most important variable inside a group is not the maximum speed of any one bike.

It is the relative speed between riders.

Even modest closing speeds can eliminate a small gap quickly.

Mixed groups should therefore agree on:

• Pace
• Acceleration
• Passing rules
• Spacing
• Regrouping procedure

A faster eBike is not automatically unsafe.

An uncontrolled speed mismatch is.

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What Research Still Needs to Answer

Several important questions remain open.

Researchers still need better data on:

• Solo versus group eBike crash rates
• Single-file versus two-abreast eBike groups
• Group size
• Assist level
• Emergency braking propagation
• Cargo eBike groups
• Group intercoms
• Rear radar
• Brake-light systems
• Rider-to-rider communication
• Near-misses inside groups

Existing crash databases often miss the very details needed to answer these questions.

That makes it important not to overstate what the science currently proves.

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Final Conclusion

Group riding changes eBike safety because riders stop operating as isolated individuals.

Spacing becomes shared.

Braking becomes contagious.

Acceleration affects everyone behind.

Formation changes how motorists overtake.

Speed differences create closing-rate problems.

And communication becomes essential because riders farther back may not be able to see what the leaders can see.

The research does not show that eBike groups are inherently more dangerous than solo riders.

It does show that groups create a different set of safety problems.

The most practical strategy is therefore:

Ride to the slowest rider. Keep enough spacing to react. Accelerate smoothly. Communicate clearly. Slow before intersections. Let every rider make their own traffic decision. And change formation according to the road rather than following one rigid rule.

A good eBike group should not feel like several riders trying to keep up with one another.

It should move like a coordinated system with enough space for everyone to make a mistake without turning it into a crash.

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