everyone should realize that e-scooters are a physically risky form of transport, especially when driven above about 20km/h.
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everyone should realize that e-scooters are a physically risky form of transport, especially when driven above about 20km/h. if you fall off, you're going to have facial trauma at a minimum. just ask my 50-something brother who got stuck with a big dental bill. ALWAYS wear a FULL FACE HELMET on these things - a bike helmet isn't enough. and NEVER EVER ride with MORE THAN ONE RIDER on board.
https://www.cbc.ca/news/health/e-scooters-pediatrician-survey-9.7305210
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everyone should realize that e-scooters are a physically risky form of transport, especially when driven above about 20km/h. if you fall off, you're going to have facial trauma at a minimum. just ask my 50-something brother who got stuck with a big dental bill. ALWAYS wear a FULL FACE HELMET on these things - a bike helmet isn't enough. and NEVER EVER ride with MORE THAN ONE RIDER on board.
https://www.cbc.ca/news/health/e-scooters-pediatrician-survey-9.7305210
why do you think e-scooters are still illegal on roads in most areas of this province? it isn't because regulators are stick-in-the-muds. it's because there's a big injury burden associated to these things.
for starters, you're riding something with no protection from the road or other road users apart from what you're wearing.
and most importantly, e-scooters are nowhere near as inherently stable as bicycles are.
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why do you think e-scooters are still illegal on roads in most areas of this province? it isn't because regulators are stick-in-the-muds. it's because there's a big injury burden associated to these things.
for starters, you're riding something with no protection from the road or other road users apart from what you're wearing.
and most importantly, e-scooters are nowhere near as inherently stable as bicycles are.
Take it from a professional physicist. (Note: physics is the branch of knowledge involved in road accident reconstruction.)
E-scooters are generally much less inherently stable than bicycles, especially at low to moderate speeds. A bicycle possesses several passive self-stabilizing mechanisms that scooters either lack or possess only weakly. As a result, scooters demand more active balance control from the rider and are less forgiving of bumps, steering errors, and surface irregularities.
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Take it from a professional physicist. (Note: physics is the branch of knowledge involved in road accident reconstruction.)
E-scooters are generally much less inherently stable than bicycles, especially at low to moderate speeds. A bicycle possesses several passive self-stabilizing mechanisms that scooters either lack or possess only weakly. As a result, scooters demand more active balance control from the rider and are less forgiving of bumps, steering errors, and surface irregularities.
*Why bicycles are surprisingly stable*
A common myth is that bicycle stability comes mainly from the spinning wheels acting as gyroscopes. Gyroscopic effects help, but they are actually not the dominant factor.
The major sources of bicycle stability are:
1. Steering geometry (trail)
• The front wheel naturally "falls into" a turn when the bike leans.
• This automatically steers the contact patch underneath the rider's centre of mass.
• The bike performs a kind of continuous self-correction.2. Large wheel diameter
• Large wheels roll smoothly over imperfections.
• Small steering disturbances produce gentler changes in direction.3. Long wheelbase
• Reduces sensitivity to perturbations.
• Creates slower, more manageable dynamics.4. Rider position
• The rider's mass is located relatively high and centred between the wheels.
• Subtle body movements can effectively influence balance.At speeds around 10-20 km/h, many bicycles are remarkably self-stabilizing. If you've ever seen a bicycle coast for a surprising distance riderless, that's evidence of these effects.
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*Why bicycles are surprisingly stable*
A common myth is that bicycle stability comes mainly from the spinning wheels acting as gyroscopes. Gyroscopic effects help, but they are actually not the dominant factor.
The major sources of bicycle stability are:
1. Steering geometry (trail)
• The front wheel naturally "falls into" a turn when the bike leans.
• This automatically steers the contact patch underneath the rider's centre of mass.
• The bike performs a kind of continuous self-correction.2. Large wheel diameter
• Large wheels roll smoothly over imperfections.
• Small steering disturbances produce gentler changes in direction.3. Long wheelbase
• Reduces sensitivity to perturbations.
• Creates slower, more manageable dynamics.4. Rider position
• The rider's mass is located relatively high and centred between the wheels.
• Subtle body movements can effectively influence balance.At speeds around 10-20 km/h, many bicycles are remarkably self-stabilizing. If you've ever seen a bicycle coast for a surprising distance riderless, that's evidence of these effects.
* Why e-scooters are less stable*
Most e-scooters move in the opposite direction on several of those factors.
1. Tiny wheels
This is probably the biggest issue.
• Typical bicycle wheel:
~66-74 cm diameter (26-29 inches)
• Typical e-scooter wheel:
~20-30 cm diameter (8-12 inches) if that
A bump that's trivial for a bicycle can represent a significant fraction of a scooter wheel's radius.
Consequences:
• Easier to be deflected by cracks and potholes.
• More sensitive to rough pavement.
• Higher likelihood of "catching" on obstacles.
• Faster steering reactions.
This alone accounts for much of the subjective feeling that scooters are twitchy.2. Short wheelbase
An e-scooter's wheelbase is often around half that of a bicycle.
The result:
• Quicker pitch motions.
• Greater sensitivity to weight shifts.
• More rapid response to steering inputs.
In control-theory language, scooters tend to have faster unstable modes and less passive damping.3. Higher steering sensitivity
The handlebars are directly above the front wheel.
On a bicycle:
• Hands are farther from the steering axis.
• Steering motions are somewhat filtered by body posture.
On a scooter:
• Small hand movements can create substantial steering angles.
This is one reason inexperienced riders often exhibit slight "wobbling" on scooters.4. Standing posture
Standing has advantages, but it changes the dynamics.
The rider's center of mass is:
• Higher above the deck than a cyclist's center of mass is above the bike frame.
• Less constrained by a saddle.
This means:
• Greater potential leverage on the vehicle.
• More body sway.
• More active balancing required.
The rider becomes part of the control system in a stronger way. -
* Why e-scooters are less stable*
Most e-scooters move in the opposite direction on several of those factors.
1. Tiny wheels
This is probably the biggest issue.
• Typical bicycle wheel:
~66-74 cm diameter (26-29 inches)
• Typical e-scooter wheel:
~20-30 cm diameter (8-12 inches) if that
A bump that's trivial for a bicycle can represent a significant fraction of a scooter wheel's radius.
Consequences:
• Easier to be deflected by cracks and potholes.
• More sensitive to rough pavement.
• Higher likelihood of "catching" on obstacles.
• Faster steering reactions.
This alone accounts for much of the subjective feeling that scooters are twitchy.2. Short wheelbase
An e-scooter's wheelbase is often around half that of a bicycle.
The result:
• Quicker pitch motions.
• Greater sensitivity to weight shifts.
• More rapid response to steering inputs.
In control-theory language, scooters tend to have faster unstable modes and less passive damping.3. Higher steering sensitivity
The handlebars are directly above the front wheel.
On a bicycle:
• Hands are farther from the steering axis.
• Steering motions are somewhat filtered by body posture.
On a scooter:
• Small hand movements can create substantial steering angles.
This is one reason inexperienced riders often exhibit slight "wobbling" on scooters.4. Standing posture
Standing has advantages, but it changes the dynamics.
The rider's center of mass is:
• Higher above the deck than a cyclist's center of mass is above the bike frame.
• Less constrained by a saddle.
This means:
• Greater potential leverage on the vehicle.
• More body sway.
• More active balancing required.
The rider becomes part of the control system in a stronger way.Overall: an e-scooter is not just slightly less stable than a bicycle; it is *fundamentally in a different stability class*, relying much more heavily on active rider balance rather than passive mechanical self-correction.
This is one reason why accident rates per kilometre travelled tend to be noticeably higher for e-scooters than for bicycles, particularly on imperfect urban pavement.
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Overall: an e-scooter is not just slightly less stable than a bicycle; it is *fundamentally in a different stability class*, relying much more heavily on active rider balance rather than passive mechanical self-correction.
This is one reason why accident rates per kilometre travelled tend to be noticeably higher for e-scooters than for bicycles, particularly on imperfect urban pavement.
upshot: don't get your child an e-scooter, get them a bicycle instead.
an added bonus if you get a bicycle without a battery: you won't find the room where it's stored engulfed in flames in 90 seconds if it catches fire.
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upshot: don't get your child an e-scooter, get them a bicycle instead.
an added bonus if you get a bicycle without a battery: you won't find the room where it's stored engulfed in flames in 90 seconds if it catches fire.
Once you understand how many elegant self-correcting mechanisms are built into a bicycle, it's hard not to appreciate that it's one of the most successful dynamically stable machines ever invented.
It's also the most thermodynamically efficient way to convey a human ever invented, among conveyances available to the general public, per person per kilometre.
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Overall: an e-scooter is not just slightly less stable than a bicycle; it is *fundamentally in a different stability class*, relying much more heavily on active rider balance rather than passive mechanical self-correction.
This is one reason why accident rates per kilometre travelled tend to be noticeably higher for e-scooters than for bicycles, particularly on imperfect urban pavement.
Driven an unlocked Scooter at 60 km/h, scary af. Every little bump took quite a lot of grip strength to correct.
But even with the common 25 km/h, bicycles are just so much less mental load to drive. -
* Why e-scooters are less stable*
Most e-scooters move in the opposite direction on several of those factors.
1. Tiny wheels
This is probably the biggest issue.
• Typical bicycle wheel:
~66-74 cm diameter (26-29 inches)
• Typical e-scooter wheel:
~20-30 cm diameter (8-12 inches) if that
A bump that's trivial for a bicycle can represent a significant fraction of a scooter wheel's radius.
Consequences:
• Easier to be deflected by cracks and potholes.
• More sensitive to rough pavement.
• Higher likelihood of "catching" on obstacles.
• Faster steering reactions.
This alone accounts for much of the subjective feeling that scooters are twitchy.2. Short wheelbase
An e-scooter's wheelbase is often around half that of a bicycle.
The result:
• Quicker pitch motions.
• Greater sensitivity to weight shifts.
• More rapid response to steering inputs.
In control-theory language, scooters tend to have faster unstable modes and less passive damping.3. Higher steering sensitivity
The handlebars are directly above the front wheel.
On a bicycle:
• Hands are farther from the steering axis.
• Steering motions are somewhat filtered by body posture.
On a scooter:
• Small hand movements can create substantial steering angles.
This is one reason inexperienced riders often exhibit slight "wobbling" on scooters.4. Standing posture
Standing has advantages, but it changes the dynamics.
The rider's center of mass is:
• Higher above the deck than a cyclist's center of mass is above the bike frame.
• Less constrained by a saddle.
This means:
• Greater potential leverage on the vehicle.
• More body sway.
• More active balancing required.
The rider becomes part of the control system in a stronger way.@adub
for science -
upshot: don't get your child an e-scooter, get them a bicycle instead.
an added bonus if you get a bicycle without a battery: you won't find the room where it's stored engulfed in flames in 90 seconds if it catches fire.
@adub yikes
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Once you understand how many elegant self-correcting mechanisms are built into a bicycle, it's hard not to appreciate that it's one of the most successful dynamically stable machines ever invented.
It's also the most thermodynamically efficient way to convey a human ever invented, among conveyances available to the general public, per person per kilometre.
bicycles have always struck physicists (e.g. me!) as almost miraculous. they are simultaneously:
• dynamically elegant,
• mechanically simple,
• energetically near-optimal, and
• extraordinarily cheap, as a conveyance.YES I DO LOVE BICYCLES. so should everyone, tbh.
with the added proviso that not everyone can ride a bicycle and that's OK. humanity will always need other transportation options. we just aren't anywhere close to bikemaxxing yet and we should be.
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@adub yikes
@Cassandra the Toronto Fire Chief has been plugging on about the dangers of messing with Lithium ion batteries in the news media lately - today for example i heard about it on the CBC Radio news. people have *died* because Li-ion batteries go up so quickly and fiercely
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Driven an unlocked Scooter at 60 km/h, scary af. Every little bump took quite a lot of grip strength to correct.
But even with the common 25 km/h, bicycles are just so much less mental load to drive.@lasagne 60km/h sounds terrifying on one of those things! i've ridden one at barely 25km/h and that's scary enough for me
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upshot: don't get your child an e-scooter, get them a bicycle instead.
an added bonus if you get a bicycle without a battery: you won't find the room where it's stored engulfed in flames in 90 seconds if it catches fire.
@adub Great explanation of the physics of e-scooters!
On the ebike battery issue, I had been told at a bike store that bikes made in Europe are safer than the cheaper Chinese ones due to more stringent battery regulations to reduce fire risk. I've often wondered if that's true, and if a big thing we're missing is better regulations to prevent fires. They're such a good car replacement that it would be great if more folk could use them with risk of house fire.
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@Cassandra the Toronto Fire Chief has been plugging on about the dangers of messing with Lithium ion batteries in the news media lately - today for example i heard about it on the CBC Radio news. people have *died* because Li-ion batteries go up so quickly and fiercely
@adub I've also heard scary things, but I don't know how inherently dangerous they are. Makes me wonder if it's another argument in favour of more widespread e-bike rentals over private purchases. Let a trained e-bike person store the batteries if they're otherwise gonna blow up the bike storage room.
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@adub I've also heard scary things, but I don't know how inherently dangerous they are. Makes me wonder if it's another argument in favour of more widespread e-bike rentals over private purchases. Let a trained e-bike person store the batteries if they're otherwise gonna blow up the bike storage room.
@Cassandra i've asked our Condo Board to seek advice on this, at the AGM. there's also a (larger) fire risk for electric cars, of course, but their components like batteries are considerably more tightly regulated.
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@adub Great explanation of the physics of e-scooters!
On the ebike battery issue, I had been told at a bike store that bikes made in Europe are safer than the cheaper Chinese ones due to more stringent battery regulations to reduce fire risk. I've often wondered if that's true, and if a big thing we're missing is better regulations to prevent fires. They're such a good car replacement that it would be great if more folk could use them with risk of house fire.
@PapyrusBrigade agreed, tighter e-bike battery safety regulations are sorely needed - so says the Toronto Fire Chief
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@Cassandra i've asked our Condo Board to seek advice on this, at the AGM. there's also a (larger) fire risk for electric cars, of course, but their components like batteries are considerably more tightly regulated.
@adub Ah. I have seen video of cars with melted batteries.
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bicycles have always struck physicists (e.g. me!) as almost miraculous. they are simultaneously:
• dynamically elegant,
• mechanically simple,
• energetically near-optimal, and
• extraordinarily cheap, as a conveyance.YES I DO LOVE BICYCLES. so should everyone, tbh.
with the added proviso that not everyone can ride a bicycle and that's OK. humanity will always need other transportation options. we just aren't anywhere close to bikemaxxing yet and we should be.
@adub Regarding "not everyone can ride", I think it goes both ways. Not everyone can easily walk, and for some folk, bicycles (and/or trikes) are an important mobility aid. I definitely noticed this in 3rd trimester pregnancy: walking was uncomfortable, running was impossible, but biking was a joy. And prior to her hip replacement surgery, my mom could barely walk, but she could still bike.
