ABS for E-Bikes

[erider_61]

I wonder how much this will add to the total cost. Great idea and I bet it will be offered by many brands, even if only as an optional upgrade.

https://electricbikeblog.com/bosch-launches-abs-pedelecs/

 

[JRA]

I think bicycles are too light to have ABS be as effective as it is on motorcycles and cars. Not to mention the added complexity and cost involved. People just need to learn to have their brakes properly adjusted and how to use them effectively and not rely on gadgets that can still allow for accidents to happen.

 

[tomjasz]

why not on ebikes?

eBikes are substantially slower. My 250cc Vespa now marketed as a 300cc with ABS is a 65-70mph vehicle. What's the speed of a typical eBike here? For me, I've toned my faster bikes down to <20mph. Riding and testing on an MSF BRC training track proved to me my current brakes are adequate. Making the complexity of hydraulic brakes unnecessary. Adding ABS on all my bikes just a waste of $$.

 

[tomjasz]

Some ebike tires suck though, like Schwalbe Marathon Plus is so slipperly in the wet / cold weather.

And it's hard to get good ratings on "sticky" tires.

 

[Roxlimn]

ABS doesn't just minimize crashes from tires skidding. They also substantially decrease stopping distances by maximizing braking power. The question is whether than incremental gain is worth the cost on a machine that only goes 20 mph.

Having said that, I have gone 30 mph, even almost 40 mph on my bike going downhill, and ABS would absolutely be nice in those situations.

 

[PaD]

eBikes are substantially slower. My 250cc Vespa now marketed as a 300cc with ABS is a 65-70mph vehicle. What's the speed of a typical eBike here? For me, I've toned my faster bikes down to <20mph. Riding and testing on an MSF BRC training track proved to me my current brakes are adequate. Making the complexity of hydraulic brakes unnecessary. Adding ABS on all my bikes just a waste of $$.

That’s good advice to practise breaking on your e-bike. I did that on my motorcycle. With my e-bike I of course tested to get feel for how the brakes functioned but I can’t say I practiced breaking.
I like the hydraulic disc brakes mainly for less adjusting. The mechanical disc brakes I had on my Gary Fisher Utopia may not have had the best feel but they could be set real ”tight” for quick braking in city riding.

 

[Mike TowpathTraveler]

Next up: Traction Control. With a press of a button on the display dashboard, that 15% soft dirt and mud grade is easily conquered. No more tire slipping out from under you as Traction Control engages the drive motor with lightning speed, 100,000 times per second!

In the Development Pipeline: Rider Airbag.....Pedestrian Avoidance Technology.....Heated and Cooled Saddle and Grips......Anti-Theft System using Iris Biometric Technology.........Industry First 96 Month Payment Plan with Platinum Service Plan & Free Towing included for the first 3000 miles or 30 months, whatever comes first! All with our first-ever 700wh battery!

 

[onlineaddy]

Holy, moly, that unit is humongous!

 

[Citycrosser]

eBikes are substantially slower. My 250cc Vespa now marketed as a 300cc with ABS is a 65-70mph vehicle. What's the speed of a typical eBike here? For me, I've toned my faster bikes down to <20mph. Riding and testing on an MSF BRC training track proved to me my current brakes are adequate. Making the complexity of hydraulic brakes unnecessary. Adding ABS on all my bikes just a waste of $$.

I've hit 60 mph while descending on my e-bike. Should I have been going that fast? No. Was it fun? Yes, and I'll do it again. Would I like to have ABS for $500? It's probably cheaper than an accident and for someone who uses their e-bike daily like a car, it's a worthwhile option to have. I could easily see justifying it for my next e-bike, which will be more of a car replacement than my current e-bike.

 

[tegnamo]

It's an impressive system for sure. I did some test stops and it works quite well. There is a point where it cuts out depending on lean angle. If you're pretty far into a corner I think the idea is that ABS can't really save you regardless.

 

[tomjasz]

I've hit 60 mph while descending on my e-bike.

So, we believe the braking system is suddenly as capable as on a scooter or MC with the addition of ABS? Well, I guess the London Bridge did get sold to AZ.

Having made near 7 decades of having fun, I'm in for a couple more. This thrills fan won't be doing it on a bike, any bike, with any bike brakes. Of course YMMV! Have fun!

 

[tomjasz]

Yikes, this was announced 2 years ago by Bosch. Interesting reviews out there...

 

[tomjasz]

If you're pretty far into a corner I think the idea is that ABS can't really save you regardless.

Another skill suited for practice on an MSF course!

 

[Citycrosser]

So, we believe the braking system is suddenly as capable as on a scooter or MC with the addition of ABS? Well, I guess the London Bridge did get sold to AZ.

Having made near 7 decades of having fun, I'm in for a couple more. This thrills fan won't be doing it on a bike, any bike, with any bike brakes. Of course YMMV! Have fun!

I wonder how the stopping distance would compare say between your 250cc scooter without ABS vs. an e-bike with ABS, both while descending the same hill at 60 mph? Based on my vehicle test experience (I used to do vehicle and motorcycle brake tests (FMVSS 122 IIRC) at a major vehicle test facility), I'm thinking the e-bike would stop faster. It might be closer than you think though. The e-bike would weigh about 250 pounds less than the scooter but it would have smaller contact patches (unless it was a fat tire bike). Given the weight difference, the e-bike (especially one with ABS) just might stop in a shorter distance.

 

[Citycrosser]

I beg to differ.

Without actually testing them side by side, I feel like my motorcycle going at the same speed, whether it's 20mph or 60mph, can stop quicker than ebikes.

I have dual 320mm disk brakes with ABS, with Bridgestone S21 Supersport tires.

Ah, but I wasn’t comparing your motorcycle to an e-bike. I was comparing a 250cc scooter without ABS. Frankly, we will never know as nobody publishes stopping distances for e-bikes let alone scooters or motorcycles.

I should add that the number and size of brake rotors is irrelevant. As long as the brakes can lock the wheel, they work! The tires do matter though as the coefficient of friction and contact patch size would be affected by tire size and compound.

 

[erider_61]

The biggest factor that comes into play is weight. A semi takes a much longer distance than a car to stop at the same speed.Even tho the semi has more contact area with the road through tires and larger brakes applied to both rig and trailer. Because of the physics involved I am going to say that an ebike will stop quicker than a 250cc scooter with ABS simply because it is lighter.

 

[erider_61]

I found this tool for calculating stopping distance of a bicycle.

http://www.exploratorium.edu/cycling/brakes2.html

Lets you plug in speed and surface type but not the weight or brake type, but gives you a rough idea what an ebikes stopping distance may be. For instance at 20mph on dry concrete it takes 15ft to completely stop.

 

[Citycrosser]

You mean nobody published motorcycles braking distance?
Unlike ebikes, in the motorcycle industry, it is very typical for reviewers to test the bike's braking distance.

The first number is 30mph-0, then 60mph-0.

2015 Kawasaki H2 - 32 ft 124 ft
2015 Aprilia Tuono - 29 ft 115 ft
2016 Victory Gunner - 37 ft 146 ft
2016 Harley Sportster - 32 ft 139 ft
2016 Yamaha Bolt - 38 ft 152 ft
2015 Honda CBR300 ABS - 34 ft 134 ft
2016 BMR R1200R - 30 ft 119 ft
2016 Yamaha FJ09 - 33 ft 133 ft
2016 Kawasaki 1000 Versys - 33 ft 129 ft
Source: Motorcycle Magazine

I also don't think "as long as you can lock the wheel, they work" theory would work.
With stronger brake, you have more control how to slow down, and typically more resistance to heat.

Honda Civic brakes can probably lock Lamborghini Aventador at 60mph if you slam on it hard enough, but I don't think the braking distance will be the same. (No I'm not an engineer so never tested it)

Sorry, I forgot about the published numbers for motorcycles. Thanks for posting those! It’s interesting that the BMW R1200R out stops a CBR300 ABS.

In regards to brake rotor size, the larger or multiple rotors simply dissipate heat better for repeated stopping, say during a track day or race. For one emergency stop, the brake rotor size, number of pistons, and number of rotors is irrelevant as long as the brakes can apply enough force to lock the wheel. In repeated emergency stops, they certainly make a difference which is why sport bikes usually have two front rotors. Actually, having that additional weight comes along with a penalty in handling as the brakes rotors and calipers add to the unsprung weight of the vehicle, but that’s a whole other topic!

 

[tomjasz]

Interesting stuff, http://www.acta.sapientia.ro/acta-emeng/C4/emeng4-3.pdf

 

[tomjasz]

I have 26” discs that stop me in good form. <smiling, and ducking>