The easiest way to improve ebike safety for newbies is regenerative braking

[taiwwa]

In response to this article here.

E-Bikes Are Booming—And Virtually Unregulated. Will This Lawsuit Make Them Safer?

Twelve-year-old Molly Steinsapir crashed onto the pavement from a Rad Power e-bike and never woke up. With a poorly regulated e-bike industry, who is responsible when a child dies?

www.bicycling.com

In short, a direct drive hub with regen programming built in would do a lot imo to improve overall bicycling safety for newbs.

1. By greatly decreasing brake pad wear which in the article is a common problem and in my ebike experience is a concern.

2. Making it possible to limit speeds by turning creating automatic regen slowdown parameters. Currently e-bikes are class 1 or class 3 which are the speeds at which motor assist stops. But on a downhill e-bikes can easily exceed those speeds and that is causing many injuries for newbies.
A regen motor could be programmed to never exceed 25mph and to regen any momentum beyond 25mph. It could be programmed to automatically slow/regen when on a steep downhill.

Imo if such a system were in place it is possible that the death could have been prevented.

 

[Chalo]

Regen braking makes it hugely more likely that the axle nuts will loosen and spin the axle, ruining the motor and very likely ejecting the wheel. That's the opposite of safety for newbies.

To prevent this kind of dangerous failure, the nuts must be checked regularly for tightness, and the wheel for any change in position in the dropouts. That's not a newbie thing to do.

For newbs, simpler is better, and slower is better. Contravening either of these basic principles is where they'll get into trouble.

 

[E-HP]

A regen motor could be programmed to never exceed 25mph and to regen any momentum beyond 25mph. It could be programmed to automatically slow/regen when on a steep downhill.

Imo if such a system were in place it is possible that the death could have been prevented.

Better install a temp sensor, since the motor will get hot as fast as it does climbing the hill as regenning down it, so you could fry your motor going down too long/steep of a hill.
Also, unless you are using variable regen, on/off regen can be dangerous on a curve if it's wet, has gravel or anything when regen can cause you to break traction. Specific to safety, regen cuts both ways, so not a clear improvement.

 

[glennb]

25mph is too fast for cities and shared paths.

If you said 15m/h you might be on to something.

Golf carts do it. Takes the fun out of them, but no doubt makes them safer.

 

[Chalo]

25mph is too fast for cities and shared paths.

Thing is, he's talking about regen. Bad idea or not, the kind of downhill that would cause you to regen to a 25 mph limit would have pedal cyclists zipping by at 30, 40, or more. I used to exceed 50 on the way to work on any given day, on pedal-only bikes.
Point is, limiting to a given speed isn't the same as powering up to that speed on flat ground with no tailwind.

On that note, pretty much any direct drive motor does this kind of speed limiting. Whatever its free speed is, if you go a couple of mph faster than that it begins to clamp your speed by stuffing the motor's excess back EMF into the battery (that is, if you haven't done something silly like putting diodes or a "battery food processor" on your battery pack). My first direct drive hub bike would cruise at about 23 on the flat, but would be limited to no more than about 29 mph on even the steepest downhills.

 

[glennb]

Yeah, my scooter and trikething slow me down descents. That’s ok. 60km/h is plenty for the scooter, and you need to be braking well before the corner at the bottom of the hill to avoid flipping the trike.

I’d hate for my bike to do that. But i’m not a beginner. It’s certainly safer to start mechanically braking at the bottom of hills from 25mph rather than anything faster than that.

 

[nicobie]

We have too many laws as it is. There comes a time when we have to accept responsibility for our own actions. Humans are basically pricks. I don't think it's possible outlaw H.S. yet.

 

[offGridDownUnder]

We have too many laws as it is. There comes a time when we have to accept responsibility for our own actions. Humans are basically pricks.

I don't want to accept responsibility for someone who won't accept it for themself.

"Laws" and the infrastructure around them are an expression of a community saying "You want the benefit of living with us, you will live in ways we agree on". I don't think this is handled well yet, but I think it's a valid approach.

A person on their own can't build a hospital, educate themself as a surgeon, develop new medicines, pump oil and refine it, develop an electric distribution system (smelt copper), develop alloys, develop battery chemistries and manufacturing processes...

A community has reach quite beyond what any person can do, and it doesn't grow on trees. It's simple - we are working together, and if you want a share of it, you will work to our agreement.

That it isn't handled perfectly in all circumstances doesn't invalidate the basic fact - you get benefit from a community, you follow that community's demands. If you don't like it, don't get involved with that community. Go somewhere else and do it all for yourself.

It is counterproductive for a community ("us") to handle this badly, to act unfairly, to permit corruption (often just through laziness), but it is appropriate for a community to sanction un-social behaviour. Participate and negotiate if you don't like it ("democracy") or go elsewhere.

I think it's more the lack of participation that is the problem.

 

[taiwwa]

We have too many laws as it is. There comes a time when we have to accept responsibility for our own actions. Humans are basically pricks. I don't think it's possible outlaw H.S. yet.

I’m not saying make laws. I’m saying the industry as a whole could engineer e-bikes in a way that would avoid the circumstances that killed those girls.

In the aftermath, it seems likely that radpowerbikes will be bankrupted by the lawsuit. I’ll bet that the prevalence of hydraulic brakes is because of this event, and imo hydraulic brakes don’t really fix the problem.

 

[Chalo]

I’m not saying make laws. I’m saying the industry as a whole could engineer e-bikes in a way that would avoid the circumstances that killed those girls.

The girl who crashed and died probably would have been moving even faster on a normal pedal powered bike. Adding dangerous "safety" features to e-bikes won't revoke gravity or stupidity.

Both gravity and stupidity have been helping to thin the herd for all history. That's not a bad thing in its own right.

The bad result of public transportation policy is when perverse incentives and insane design cause the people who make bad decisions for everybody (car drivers) to selectively delete people who make better decisions (peds and cyclists).

 

[UtahPete]

In response to this article here.

E-Bikes Are Booming—And Virtually Unregulated. Will This Lawsuit Make Them Safer?

Twelve-year-old Molly Steinsapir crashed onto the pavement from a Rad Power e-bike and never woke up. With a poorly regulated e-bike industry, who is responsible when a child dies?

www.bicycling.com

The parents should be held criminally liable, rather than seeking to profit off this tragedy of their own making.

 

[UtahPete]

I don't want to accept responsibility for someone who won't accept it for themself.

"Laws" and the infrastructure around them are an expression of a community saying "You want the benefit of living with us, you will live in ways we agree on". I don't think this is handled well yet, but I think it's a valid approach.

A person on their own can't build a hospital, educate themself as a surgeon, develop new medicines, pump oil and refine it, develop an electric distribution system (smelt copper), develop alloys, develop battery chemistries and manufacturing processes...

A community has reach quite beyond what any person can do, and it doesn't grow on trees. It's simple - we are working together, and if you want a share of it, you will work to our agreement.

That it isn't handled perfectly in all circumstances doesn't invalidate the basic fact - you get benefit from a community, you follow that community's demands. If you don't like it, don't get involved with that community. Go somewhere else and do it all for yourself.

It is counterproductive for a community ("us") to handle this badly, to act unfairly, to permit corruption (often just through laziness), but it is appropriate for a community to sanction un-social behaviour. Participate and negotiate if you don't like it ("democracy") or go elsewhere.

I think it's more the lack of participation that is the problem.

Bravo. When individual freedoms are not connected to personal responsibility for one's actions, we have the growing chaos of American society.

 

[E-HP]

I’m not saying make laws. I’m saying the industry as a whole could engineer e-bikes in a way that would avoid the circumstances that killed those girls.

In the aftermath, it seems likely that radpowerbikes will be bankrupted by the lawsuit. I’ll bet that the prevalence of hydraulic brakes is because of this event, and imo hydraulic brakes don’t really fix the problem.

Anything could lead to a crash, but speed kills. A bicycle helmet isn't adequate protection when going ebike speeds. It seems a kid wanted an ebike because all the kids have them in Pacific Palisades, and the parent pulled out a credit card, but didn't provide sufficient head protection or training. We rode dirt bikes at that age, but always wore the good helmets. You learn about that from the adults.
I have hydraulic brakes and steep hills, and I still have to grab hard to slow or stop, even with the 4 piston calipers. I see those Rad bikes a lot. They can stop on a hill, but I'm sure it takes a decent grip, and kids riding 2 up are about the weight of an adult, but don't have the grip. There probably should have been a no passenger rule, in addition to better head protection and general parenting.

 

[taiwwa]

Anything could lead to a crash, but speed kills. A bicycle helmet isn't adequate protection when going ebike speeds. It seems a kid wanted an ebike because all the kids have them in Pacific Palisades, and the parent pulled out a credit card, but didn't provide sufficient head protection or training. We rode dirt bikes at that age, but always wore the good helmets. You learn about that from the adults.
I have hydraulic brakes and steep hills, and I still have to grab hard to slow or stop, even with the 4 piston calipers. I see those Rad bikes a lot. They can stop on a hill, but I'm sure it takes a decent grip, and kids riding 2 up are about the weight of an adult, but don't have the grip. There probably should have been a no passenger rule, in addition to better head protection and general parenting.

I mean, long descents are also a problem for me in my regular bicycle because of brake issues.

I was surprised to learn that regen wasn’t widely available for e-bikes. Regen is present in every electric and hybrid vehicle and is a pillar of the drivetrains.

The marketing materials also encouraged this dangerous usage by depicting two people on an ebike.

I don’t think it’s a grip issue, which is why I say that hydraulic brakes are not a solution. All that hydraulic brakes do is increase grip by maybe 25%. But brake pad wear is still the same. And I’m not sure how difficult maintenance is on hydraulic but it looks more involved than cable pull brakes and again that is imo a failure point.

 

[E-HP]

I don’t think it’s a grip issue, which is why I say that hydraulic brakes are not a solution. All that hydraulic brakes do is increase grip by maybe 25%. But brake pad wear is still the same. And I’m not sure how difficult maintenance is on hydraulic but it looks more involved than cable pull brakes and again that is imo a failure point.

By grip, I'm talking about little 11 year old hands pulling on levers made for adults.

 

[taiwwa]

By grip, I'm talking about little 11 year old hands pulling on levers made for adults.

Right but it appears that the brakes on that bike were well worn out by then anyways.

 

[fill]

how about gun laws then? he says tossing a match into the room full of petrol (gasolene) as he walks out..

 

[neptronix]

I agree regenerative brakes would help, but a regular bike's brakes could also fail going down a 14% grade.

I had a white knuckle moment going down these mountains once, brakes started fading to nothing due to heat when i had a BBS02 for a brief moment. Ended up having to stop a few times to cool the brakes down.

That's a problem i never had with a DD. The problem with a DD is getting up the same grade without the motor melting, lol.

 

[amberwolf]

2. Making it possible to limit speeds by turning creating automatic regen slowdown parameters. Currently e-bikes are class 1 or class 3 which are the speeds at which motor assist stops. But on a downhill e-bikes can easily exceed those speeds and that is causing many injuries for newbies.
A regen motor could be programmed to never exceed 25mph and to regen any momentum beyond 25mph. It could be programmed to automatically slow/regen when on a steep downhill.

What does the system do when the battery is too full or too old to accept a charge at sufficient current to perform this braking?

It can't do the regen braking then, not without potential battery damage (which could lead to a fire), or without potential controller damage because of the battery BMS shutting off, causing a spike in voltage inside the controller that could blow up it's FETs***.

Since the rider would be expecting the system to automatically do the braking so they don't have to, they would not know to manually do anything about it, and this would be a much worse safety problem.

If people aren't willing to maintain their critical safety systems (like brakes) or have them maintained by someone else (bike shops, etc), it's not something you can engineer around by making the system even more complex, requring even more maintenance and even more user-checks before and during a ride....


*** if that particular scenario happened, the FETs usually would fail shorted, and this would then lockup the motor, and on a direct-drive motor it would lockup the wheel, and in a front wheel it would probably flip the rider over on their head.

I'd call that an even worse safety issue than the other stuff.

 

[Papa]

** NOTE: the quote below is not in reference to Molly's tragic incident, but a completely different Rad rider's unfortunate mishap, but mentioned in the very same article the OP posted.**

"She estimates she was traveling 25 to 30 miles per hour and says her front wheel was wobbling."

My observation?....

https://www.reddit.com/r/bikewrench/comments/o641zs

The video:

https://packaged-media.redd.it/g3wvrfmakx671/pb/m2-res_1080p.mp4?m=DASHPlaylist.mpd&v=1&e=1703678400&s=a7d1b56429d2f3c63c305ba4a557826989aec2f7#t=0

Isolated?... I think not:

radrunner shimmy - Google Search

www.google.com

Speed wobbles: How they start and how to stop them

You finish climbing, crest the hill, then start flying down the other side. And then, out of nowhere, it happens. You’re not riding recklessly; you’re not

velo.outsideonline.com

 

[taiwwa]

What does the system do when the battery is too full or too old to accept a charge at sufficient current to perform this braking?

It can't do the regen braking then, not without potential battery damage (which could lead to a fire), or without potential controller damage because of the battery BMS shutting off, causing a spike in voltage inside the controller that could blow up it's FETs***.

Since the rider would be expecting the system to automatically do the braking so they don't have to, they would not know to manually do anything about it, and this would be a much worse safety problem.

If people aren't willing to maintain their critical safety systems (like brakes) or have them maintained by someone else (bike shops, etc), it's not something you can engineer around by making the system even more complex, requring even more maintenance and even more user-checks before and during a ride....


*** if that particular scenario happened, the FETs usually would fail shorted, and this would then lockup the motor, and on a direct-drive motor it would lockup the wheel, and in a front wheel it would probably flip the rider over on their head.

I'd call that an even worse safety issue than the other stuff.

I drive an electric car and there are times when I am driving it that if the battery is charged too much then there is no regenerative braking.

I’m very used to regen braking so the loss of regen is a surprise. But it usually quickly goes away in a few minutes as I use up charge.

What I mean is that there is an instance where I experience a loss in expected braking power.

The way to prevent this from happening is by not charging the battery all the way.

This is also a pretty rare occurrence because I rarely charge the battery to 100.

 

[Big Tom]

I mean, long descents are also a problem for me in my regular bicycle because of brake issues.

I was surprised to learn that regen wasn’t widely available for e-bikes. Regen is present in every electric and hybrid vehicle and is a pillar of the drivetrains.

The marketing materials also encouraged this dangerous usage by depicting two people on an ebike.

I don’t think it’s a grip issue, which is why I say that hydraulic brakes are not a solution. All that hydraulic brakes do is increase grip by maybe 25%. But brake pad wear is still the same. And I’m not sure how difficult maintenance is on hydraulic but it looks more involved than cable pull brakes and again that is imo a failure point.

Regen braking "MIGHT" help a little, but it will also create other issues. What if a rider wants to pedal without applying any power from the electric assist. Regen works by generating power from the added resistance of the motor capable of creating regenitive power (i know a simplistic statement). I personally do not want regenitive power as I do not want to have to apply extra force to move that wheel when no power is added. Electric assist was first designed to assist riders when needed (for hills ect.) not as a full time power motor cycle.

The largest issue you is not regenitive power or the lack of, but (very sadly) it was a rider not capable of safely using that cycle. I believe that most 11 or 12 year olds do not have the maturity to handle electric assist cycles, especially if they can get over 20 miles per hour. Yes some do have the maturity but those children will have had adults teaching them responsibility (like how to do things safely and dangers involved) growing up. Most young children do not have life experiences for them to truly understand dangers.

As for people talking about speeds, my trike can easily go faster (without assisted power) then with the assist being used. Does this mean there needs to be regen braking on an non assisted cycle to slow down that cycle.

It is very sad that this child (or any other child) has lost their life. I do feel it is the responsibility of the guardian to make sure younger riders are mature enough to operate a cycle like these. Not to just grant permission because others have them.

Where I live, you need to be 16 to be able to ride an assisted cycle (age where a vehicle license can be obtained). I have seen people ride assisted cycles (even assisted scooters) with no ability to safely handle them, also without any regard for the safety of others.

Tom

 

[nicobie]

It is very sad that this child (or any other child) has lost their life. I do feel it is the responsibility of the guardian to make sure younger riders are mature enough to operate a cycle like these. Not to just grant permission because others have them.


Tom

 

[neptronix]

If i was building for this scenario..

I'd think about some of the more effective safety features:
- regen if possible
- oversized brakes regardless of whether we have regen or not.
- UL rated battery
- Motor power rated for exactly the legal limit, bike + parts rated for +10mph over that considering we may end up in an unexpected downhill scenario, especially in a mountainous area like California, where most of these bikes will be sold.
- Numerous checks on throttle state anomalies, etc..

At this point you can say you did 'due diligence'. When someone dies, and you find yourself in legal heat, you can point to the fact that you made the vehicle as safe as possible, and they were way out of bounds with how they were operating it.

Because we have no vehicle-specific safety regulations for prebuilt electric bikes, the race to the bottom effect means whoever goes above and beyond the bare minimum in vehicle design can lose in the market because consumers buy the cheapest ebikes for sale more often than not; which further incentivizes bike makers to churn out e-BSO's.

We can probably expect regulations to come in this arena. Let's hope they're at least somewhat rational.

And maybe it's for the better because a lot of people's first bicycle is going to be a prebuilt of, all too often, questionable quality.