Useful Definitions Of ebikes for Regulatory Purposes

Right now governments are so anxious to get motorists off carbon and onto any ebike they may be willing to look the other way as everyone "tunes" or "unlocks" ebike controllers.

In Germany you can go 50 km/hr without any legal problems.

But as tires get fatter and motors get more powerful the distinction between an e motorcycle and ebike may get blurred.

Eventually they may clamp down.

One category that should never be regulated would be like that Spanish bike that stays in a weak regeneration mode most of the time. You only use the assist when needed. You never plug it in.

Power for short distances is a great safety feature.

There may be other easy to define categories that would be easy to enforce.


Bret Cahill

On 14/01/2021 00:13, Bret Cahill wrote:

One category that should never be regulated would be like that
Spanish bike that stays in a weak regeneration mode most of the time.
You only use the assist when needed. You never plug it in.

Perpetual motion at last.

One category that should never be regulated would be like that
Spanish bike that stays in a weak regeneration mode most of the time.
You only use the assist when needed. You never plug it in.

Perpetual motion at last.

You eat more food in regen so it's higher carbon than plugging in, even ignoring round trip inefficiencies.

Another advantage is down hill commutes in the morning when it's cold then returning uphill when it's warm. Use regen in the morning to keep warm and assist back up to stay cool.

On 14/01/2021 23:59, Bret Cahill wrote:

One category that should never be regulated would be like that
Spanish bike that stays in a weak regeneration mode most of the
time. You only use the assist when needed. You never plug it in.

Perpetual motion at last.

You eat more food in regen so it's higher carbon than plugging in,
even ignoring round trip inefficiencies.

It isn't possible to ignore inefficiencies. A hybrid car works because
the engine is much more powerful than needed for cruising. Once a car's
frictional losses are covered, additional energy can be extracted
without further frictional loss (eg piston, gearbox, tyres etc) so is at
best thermal efficiency.

Another advantage is down hill commutes in the morning when it's cold
then returning uphill when it's warm. Use regen in the morning to
keep warm and assist back up to stay cool.

It is possible to extract some energy going downhill by recovering
energy instead of using friction brakes but for moderate hills, energy
lost to brakes is insignificant compared to that lost to air drag.

One category that should never be regulated would be like that
Spanish bike that stays in a weak regeneration mode most of the
time. You only use the assist when needed. You never plug it in.

Perpetual motion at last.

You eat more food in regen so it's higher carbon than plugging in,
even ignoring round trip inefficiencies.
It isn't possible to ignore inefficiencies.

Engineers do it all the time in initial calculations to determine best possible scenarios. These work as a fortiori arguments to quickly eliminate the less than 100% efficiency schemes.

Here round trip inefficiencies are the icing on the cake argument for plugging in. Food is high carbon. Electricity from wind and solar is low carbon. Pedaling in regen is high carbon.

Considering inefficiencies plugging in is even lower carbon.

There are other considerations like health. President Biden uses a stationary bicycle for exercise but they may give second servings at the White House.

I don't have time to buy, prepare and eat tons of food. It's easier to plug in if I need longer range.

A hybrid car works because
the engine is much more powerful than needed for cruising. Once a car's
frictional losses are covered, additional energy can be extracted
without further frictional loss (eg piston, gearbox, tyres etc) so is at
best thermal efficiency.

Adiabatic engines only work efficiently at a narrow rpm sweet spot. That problem has never been solved because adiabatic = high speed. A turbo engineer at a well known company working on fuel cells said he could get a good compression efficiency over a broad low pressure range. I asked for a drawing but he declined.

Such a drawing could reveal the Hand of God.

On the other hand, in just a few years, Tesla managed to get high efficiency over a huge RPM range with some hybrid combination of magnet reluctance motors.

Another advantage is down hill commutes in the morning when it's cold
then returning uphill when it's warm. Use regen in the morning to
keep warm and assist back up to stay cool.
It is possible to extract some energy going downhill by recovering
energy instead of using friction brakes but for moderate hills, energy
lost to brakes is insignificant compared to that lost to air drag.

Maybe 10% in a congested city with steep hills like San Francisco.

Go Swissdrive has some wires that I could hook up to the brake levers for regenerative braking. Not sure if I should bother trying to get them to work. Almost all my cycling is on flat land. I brake more often for trucks running me off the road than stop signs and lights.

Flats are a bigger fish to fry. I cycle in regen to keep warm or look for stuff on the side of the road.

Regen has no serious purpose IMO. I'm an extraordinarily lazy bike mechanic and I have flat axle bearings to prove it.

The wires to the brake levers probably won't get hooked up.



Bret Cahill

On 24/01/2021 03:25, Bret Cahill wrote:

One category that should never be regulated would be like
that Spanish bike that stays in a weak regeneration mode
most of the time. You only use the assist when needed. You
never plug it in.

Perpetual motion at last.

You eat more food in regen so it's higher carbon than plugging
in, even ignoring round trip inefficiencies.
It isn't possible to ignore inefficiencies.

Engineers do it all the time in initial calculations to determine
best possible scenarios.

As back of envelope sketches, certainly. Then it has to be worked down a
practical solution. It means that your bike that is never plugged in
looks as though it would fall down as a practical solution.

These work as a fortiori arguments to quickly eliminate the less than
100% efficiency schemes.

Here round trip inefficiencies are the icing on the cake argument
for plugging in. Food is high carbon. Electricity from wind and
solar is low carbon. Pedaling in regen is high carbon.

Your starting point (at the top) was a bike that is never plugged in.
Now you are talking about plug in. It can be agreed that electricity is
likely to be more efficient than food.

Considering inefficiencies plugging in is even lower carbon.

There are other considerations like health. President Biden uses a
stationary bicycle for exercise but they may give second servings at
the White House.

I don't have time to buy, prepare and eat tons of food. It's easier
to plug in if I need longer range.

A hybrid car works because the engine is much more powerful than
needed for cruising. Once a car's frictional losses are covered,
additional energy can be extracted without further frictional loss
(eg piston, gearbox, tyres etc) so is at best thermal efficiency.

Adiabatic engines only work efficiently at a narrow rpm sweet spot.

What is your definition of "efficiently"? Internal friction (gas flow,
pistons, bearings, valves etc) is the most significant contributor to
final efficiency.

For instance, a conventional engine of 1.5 litres typically has an
internal frictional loss of about 3kW/1000rpm.

For any value of thermal efficiency, it can be seen that delivered
efficiency improves as the load increases. At a steady 60mph on the
flat, a car consumes about 12-15kW from the crank so 9kW of internal
loss is significant. Hence the idea to make the engine work hard part
time to store potential energy or electrical energy, then turn the
engine off for another part seems a valid method to improve consumption.
Pulse width modulate it, in effect.

For this reason it is possible that a (non-hybrid) car can consume less
fuel on an undulating road than on a flat road. Anecdotally, I believe
it to be the case.

That problem has never been solved because adiabatic = high speed.

There is no benefit in raising speed to gain an adiabatic improvement if
it results in increased frictional loss.

A turbo engineer at a well known company working on fuel cells said
he could get a good compression efficiency over a broad low pressure
range. I asked for a drawing but he declined.

It is said that the modern turbocharged formula 1 engine can reach 50%
thermal efficiency and even without electrical assistance they have a
very broad operating band compared to racing engines of the past.

I have moved from a 4 cylinder 1.4l engine with 20mph/1000 top gear to a
turbocharged 3 cylinder 1.0l engine with 30mph/1000rpm. It takes about
25% less fuel and the wider working band produces a better driving
experience.

Losing a cylinder reduces the friction coefficient and although a
turbocharger is an adiabatic nightmare it provides a beneficial
opportunity through the gearing.

Such a drawing could reveal the Hand of God.

Well, if there is a God it was the creator of physics.

On the other hand, in just a few years, Tesla managed to get high
efficiency over a huge RPM range with some hybrid combination of
magnet reluctance motors.

Another advantage is down hill commutes in the morning when it's
cold then returning uphill when it's warm. Use regen in the
morning to keep warm and assist back up to stay cool.
It is possible to extract some energy going downhill by recovering
energy instead of using friction brakes but for moderate hills,
energy lost to brakes is insignificant compared to that lost to
air drag.

Maybe 10% in a congested city with steep hills like San Francisco.

Go Swissdrive has some wires that I could hook up to the brake
levers for regenerative braking. Not sure if I should bother trying
to get them to work. Almost all my cycling is on flat land. I brake
more often for trucks running me off the road than stop signs and
lights.

Unless your e-bike has the means to reverse electrical flow, cables are
not going to make any difference. E-bikes typically don't have the
necessary hardware because it isn't worth the expense.

Even if it was not expense, the amount of energy available for
harvesting would not make it worth the bother.

Flats are a bigger fish to fry. I cycle in regen to keep warm or
look for stuff on the side of the road.

Regen has no serious purpose IMO. I'm an extraordinarily lazy bike
mechanic and I have flat axle bearings to prove it.

The wires to the brake levers probably won't get hooked up.



Bret Cahill

One category that should never be regulated would be like
that Spanish bike that stays in a weak regeneration mode
most of the time. You only use the assist when needed. You
never plug it in.

Perpetual motion at last.

You eat more food in regen so it's higher carbon than plugging
in, even ignoring round trip inefficiencies.
It isn't possible to ignore inefficiencies.

Engineers do it all the time in initial calculations to determine
best possible scenarios.
As back of envelope sketches, certainly. Then it has to be worked down a
practical solution. It means that your bike that is never plugged in
looks as though it would fall down as a practical solution.
These work as a fortiori arguments to quickly eliminate the less than
100% efficiency schemes.

Here round trip inefficiencies are the icing on the cake argument
for plugging in. Food is high carbon. Electricity from wind and
solar is low carbon. Pedaling in regen is high carbon.
Your starting point (at the top) was a bike that is never plugged in.
Now you are talking about plug in. It can be agreed that electricity is
likely to be more efficient than food.

Several orders of magnitude but who's counting?

Considering inefficiencies plugging in is even lower carbon.

There are other considerations like health. President Biden uses a
stationary bicycle for exercise but they may give second servings at
the White House.

I don't have time to buy, prepare and eat tons of food. It's easier
to plug in if I need longer range.

A hybrid car works because the engine is much more powerful than
needed for cruising. Once a car's frictional losses are covered,
additional energy can be extracted without further frictional loss
(eg piston, gearbox, tyres etc) so is at best thermal efficiency.

Adiabatic engines only work efficiently at a narrow rpm sweet spot.

What is your definition of "efficiently"?

New PCB and other e aircraft motors are up to 97%.

They have such a high power / weight ratio even the 3% heat needs to be liquid cooled.

Scale down to an ebike and the worm drive would be the only thing you could see in the down tube.

Use pure aluminum for better heat transfer and not run it all the time and maybe you could get away with air cooling.

Internal friction (gas flow,
pistons, bearings, valves etc) is the most significant contributor to
final efficiency.

For instance, a conventional engine of 1.5 litres typically has an
internal frictional loss of about 3kW/1000rpm.

The 800 lb gorilla is the thermocycle, not internal friction. You want high power density for at least two reasons but that's only possible with adiabatic engines.

Aircraft gas turbines are typical. They either waste fuel on take off or cruise so they spreadsheet it and waste energy on both.

Rolls, GE etc. have hundreds maybe thousands of engineers looking at that spread sheet like the Banderlog watching Kaa.

For any value of thermal efficiency, it can be seen that delivered
efficiency improves as the load increases. At a steady 60mph on the
flat, a car consumes about 12-15kW from the crank so 9kW of internal
loss is significant. Hence the idea to make the engine work hard part
time to store potential energy or electrical energy, then turn the
engine off for another part seems a valid method to improve consumption.
Pulse width modulate it, in effect.

For this reason it is possible that a (non-hybrid) car can consume less
fuel on an undulating road than on a flat road. Anecdotally, I believe
it to be the case.
That problem has never been solved because adiabatic = high speed.
There is no benefit in raising speed to gain an adiabatic improvement if
it results in increased frictional loss.
A turbo engineer at a well known company working on fuel cells said
he could get a good compression efficiency over a broad low pressure
range. I asked for a drawing but he declined.
It is said that the modern turbocharged formula 1 engine can reach 50%
thermal efficiency and even without electrical assistance they have a
very broad operating band compared to racing engines of the past.

They whine about weight even more than cyclists. They have no choice but to go to the 12kW/ kg liquid cooled motors.

I have moved from a 4 cylinder 1.4l engine with 20mph/1000 top gear to a
turbocharged 3 cylinder 1.0l engine with 30mph/1000rpm. It takes about
25% less fuel and the wider working band produces a better driving
experience.

Diamler quit researching new diesel engine technology last year.

That is a milestone.

Losing a cylinder reduces the friction coefficient and although a
turbocharger is an adiabatic nightmare it provides a beneficial
opportunity through the gearing.
Such a drawing could reveal the Hand of God.
Well, if there is a God it was the creator of physics.
On the other hand, in just a few years, Tesla managed to get high
efficiency over a huge RPM range with some hybrid combination of
magnet reluctance motors.

Another advantage is down hill commutes in the morning when it's
cold then returning uphill when it's warm. Use regen in the
morning to keep warm and assist back up to stay cool.
It is possible to extract some energy going downhill by recovering
energy instead of using friction brakes but for moderate hills,
energy lost to brakes is insignificant compared to that lost to
air drag.

Maybe 10% in a congested city with steep hills like San Francisco.

Go Swissdrive has some wires that I could hook up to the brake
levers for regenerative braking. Not sure if I should bother trying
to get them to work. Almost all my cycling is on flat land. I brake
more often for trucks running me off the road than stop signs and
lights.
Unless your e-bike has the means to reverse electrical flow, cables are
not going to make any difference.

Hygia brakes have a magnet switch in the lever for regeneration.

It can't be very efficient at low RPM as the amp meter only reads -0.4 when I feel like I'm putting out 100 watts.

Use it as a diagnostic tool for the virus.

E-bikes typically don't have the
necessary hardware because it isn't worth the expense.

Mine must have some kind of 3 phase inverter. Three large power wires go to the coils.

Even if it was not expense, the amount of energy available for
harvesting would not make it worth the bother.

Maybe in hilly congested areas you can extend your range a few km.

In a few years ebike regen will look silly/quaint.

Flats are a bigger fish to fry. I cycle in regen to keep warm or
look for stuff on the side of the road.

Regen has no serious purpose IMO. I'm an extraordinarily lazy bike
mechanic and I have flat axle bearings to prove it.

The wires to the brake levers probably won't get hooked up.



Bret Cahill

On 26/01/2021 04:53, Bret Cahill wrote:

Your starting point (at the top) was a bike that is never plugged
in. Now you are talking about plug in. It can be agreed that
electricity is likely to be more efficient than food.

Several orders of magnitude but who's counting?

You could grow your own turnips and cook them with your own wood.

What is your definition of "efficiently"?

New PCB and other e aircraft motors are up to 97%.

80% from wall plug to battery, 95% from battery to motor. Times 97%
makes 69%.

Internal friction (gas flow, pistons, bearings, valves etc) is the
most significant contributor to final efficiency.

For instance, a conventional engine of 1.5 litres typically has an
internal frictional loss of about 3kW/1000rpm.

The 800 lb gorilla is the thermocycle, not internal friction. You
want high power density for at least two reasons but that's only
possible with adiabatic engines.

The 800 lb gorilla is the excess weight of modern cars. Your car culture
improved when your manufacturers learnt a few things from Japan and
Europe in the 70s but some of your countrymen still seem to think it is
their duty to move organic material from ground to atmosphere.

Adiabatic loss is an energy loss, mechanical friction is an energy loss.
The aerodynamics involved in pumping the air from intake to tail creates
an energy loss. Chasing gains from any of these makes a difference.

Much like the things a cyclist has to deal with.

Aircraft gas turbines are typical. They either waste fuel on take
off or cruise so they spreadsheet it and waste energy on both.

Rolls, GE etc. have hundreds maybe thousands of engineers looking at
that spread sheet like the Banderlog watching Kaa.

So long as it is considered necessary to move things and people around
the world, waste is inevitable due to distances covered.

It is said that the modern turbocharged formula 1 engine can reach
50% thermal efficiency and even without electrical assistance they
have a very broad operating band compared to racing engines of the
past.

They whine about weight even more than cyclists. They have no choice
but to go to the 12kW/kg liquid cooled motors.

Racing drivers want to be able to make mistakes without dying so have
created a conflicting requirement. The hybrid technology is interesting
but it's (I think the modern phrase is) virtue signalling compared to
the conspicuous consumption of the whole circus.

Formula E racing is a fraud because they fill the batteries from diesel
generators.

I have moved from a 4 cylinder 1.4l engine with 20mph/1000 top gear
to a turbocharged 3 cylinder 1.0l engine with 30mph/1000rpm. It
takes about 25% less fuel and the wider working band produces a
better driving experience.

Diamler quit researching new diesel engine technology last year.

At some point in the past, large corporations lost interest in steam
engines.

It is possible to extract some energy going downhill by
recovering energy instead of using friction brakes but for
moderate hills, energy lost to brakes is insignificant compared
to that lost to air drag.

Maybe 10% in a congested city with steep hills like San
Francisco.

Maybe?

Go Swissdrive has some wires that I could hook up to the brake
levers for regenerative braking. Not sure if I should bother
trying to get them to work. Almost all my cycling is on flat
land. I brake more often for trucks running me off the road than
stop signs and lights.
Unless your e-bike has the means to reverse electrical flow, cables
are not going to make any difference.

Hygia brakes have a magnet switch in the lever for regeneration.

Do anything you like with the lever, it makes no difference unless the
power electronics between battery and motor provide reverse flow.

Even if it was not expense, the amount of energy available for
harvesting would not make it worth the bother.

Maybe in hilly congested areas you can extend your range a few km.

With a bit of experience people can get on a bike and adjust their
output so they reach their destination. If they suddenly become
incapacitated within sight of their destination, they are doing
something wrong that won't be fixed with regen.

Your starting point (at the top) was a bike that is never plugged
in. Now you are talking about plug in. It can be agreed that
electricity is likely to be more efficient than food.

Several orders of magnitude but who's counting?
You could grow your own turnips and cook them with your own wood.
What is your definition of "efficiently"?

New PCB and other e aircraft motors are up to 97%.

80% from wall plug to battery, 95% from battery to motor. Times 97%
makes 69%.

That still beats anything in ICE or even combined cycle.

And who cares about the loss charging the battery?

Internal friction (gas flow, pistons, bearings, valves etc) is the
most significant contributor to final efficiency.

For instance, a conventional engine of 1.5 litres typically has an
internal frictional loss of about 3kW/1000rpm.

The 800 lb gorilla is the thermocycle, not internal friction. You
want high power density for at least two reasons but that's only
possible with adiabatic engines.

The 800 lb gorilla is the excess weight of modern cars. Your car culture
improved when your manufacturers learnt a few things from Japan and
Europe in the 70s but some of your countrymen still seem to think it is
their duty to move organic material from ground to atmosphere.

Architecture and vehicle design merely reflect the political situation. It's the same 200 proof fascism as behind the thick "Mussolini" columns in older Italian train stations. The governator recognized it for what it was.

See the revived post on accelerating to red lights for some evidence of where the U. S. is politically.

Musk simply exploits the fascism to shift to green energy. Such a dicey maneuver needs to be watched very carefully.


Adiabatic loss is an energy loss, mechanical friction is an energy loss.

Adiabatic thermocycles result in an order of magnitude more energy loss than friction.

Stirling attempted a better cycle but the heat transfer isn't possible.

The only place where you get a Carnot thermocycle is with a hurricane where the HX area is a good part of the ocean.

The aerodynamics involved in pumping the air from intake to tail creates
an energy loss. Chasing gains from any of these makes a difference.

Much like the things a cyclist has to deal with.
Aircraft gas turbines are typical. They either waste fuel on take
off or cruise so they spreadsheet it and waste energy on both.

Rolls, GE etc. have hundreds maybe thousands of engineers looking at
that spread sheet like the Banderlog watching Kaa.
So long as it is considered necessary to move things and people around
the world, waste is inevitable due to distances covered.
It is said that the modern turbocharged formula 1 engine can reach
50% thermal efficiency and even without electrical assistance they
have a very broad operating band compared to racing engines of the
past.

They whine about weight even more than cyclists. They have no choice
but to go to the 12kW/kg liquid cooled motors.
Racing drivers want to be able to make mistakes without dying so have
created a conflicting requirement. The hybrid technology is interesting
but it's (I think the modern phrase is) virtue signalling compared to
the conspicuous consumption of the whole circus.

Formula E racing is a fraud because they fill the batteries from diesel
generators.
I have moved from a 4 cylinder 1.4l engine with 20mph/1000 top gear
to a turbocharged 3 cylinder 1.0l engine with 30mph/1000rpm. It
takes about 25% less fuel and the wider working band produces a
better driving experience.

Diamler quit researching new diesel engine technology last year.
At some point in the past, large corporations lost interest in steam
engines.
It is possible to extract some energy going downhill by
recovering energy instead of using friction brakes but for
moderate hills, energy lost to brakes is insignificant compared
to that lost to air drag.

Maybe 10% in a congested city with steep hills like San
Francisco.
Maybe?
Go Swissdrive has some wires that I could hook up to the brake
levers for regenerative braking. Not sure if I should bother
trying to get them to work. Almost all my cycling is on flat
land. I brake more often for trucks running me off the road than
stop signs and lights.
Unless your e-bike has the means to reverse electrical flow, cables
are not going to make any difference.

Hygia brakes have a magnet switch in the lever for regeneration.
Do anything you like with the lever, it makes no difference unless the
power electronics between battery and motor provide reverse flow.

It would take 13 hours of peddling but a negative assist will charge up the battery.

The brake lever switch is just a faster way to the -3 assist.

Even if it was not expense, the amount of energy available for
harvesting would not make it worth the bother.

Maybe in hilly congested areas you can extend your range a few km.
With a bit of experience people can get on a bike and adjust their
output so they reach their destination. If they suddenly become
incapacitated within sight of their destination, they are doing
something wrong that won't be fixed with regen.

I like watching the "distance to charge" screen. It's based on past history and current consumption. It's some kind of a weighted average, probably exponential decay. If I switch to a low assist the range will quickly increase then level off then slowly drop.

The nominal distance depends on the charge and is actually about the real range for 80% #1 /20% #2, flat land no wind, about twice the actual if it's 100% #2, 3X in #3.

I never use 4 or 5 and don't even know if they work.


Bret Cahill

On 27/01/2021 06:23, Bret Cahill wrote:

Your starting point (at the top) was a bike that is never
plugged in. Now you are talking about plug in. It can be
agreed that electricity is likely to be more efficient than
food.

Several orders of magnitude but who's counting?
You could grow your own turnips and cook them with your own wood.
What is your definition of "efficiently"?

New PCB and other e aircraft motors are up to 97%.

80% from wall plug to battery, 95% from battery to motor. Times 97%
makes 69%.

That still beats anything in ICE or even combined cycle.

And who cares about the loss charging the battery?

Not caring about it does not make it go away.

See the revived post on accelerating to red lights for some evidence
of where the U. S. is politically.

Musk simply exploits the fascism to shift to green energy. Such a
dicey maneuver needs to be watched very carefully.

I am not familiar enough with the USA but in Britain traffic lights are
deliberately designed to make the traffic stop, rather than keep things
moving. The desire to "beat the lights" is the inevitable consequence.

The nice thing about electric cars is that they don't make appalling
noises when accelerating.

Recently there was a fashion for the manufacturers of some cars to
inject fuel on overrun to make popping noises for a faux legacy sound.
When they overtake me on my bike it's bad enough when a car barks on
acceleration but when they pop on a shift it gives me tinnitus.
Fortunately it was banned about a year ago.

In our modern times it should be simple to electronically emulate the
noises of any antique vehicle for the benefit of the occupants alone
without annoying those outside. I can even imagine a Tesla with a third
pedal and a stick to allow the hair shirt brigade to get the full
experience. It could ruin the steering and brakes at the same time.
....perhaps change pedal mode when a Model T is dialled in.

Adiabatic loss is an energy loss, mechanical friction is an energy
loss.

Adiabatic thermocycles result in an order of magnitude more energy
loss than friction.

With your V8s of the 1960s, 8-12mpg was a combination of technology and
cheapest possible manufacturing, not adiabatic losses.