Know Your Average Stopping Distance?

[The duke]

I was at my LBS getting my cassette replaced. Said LBS does not sell ebikes and is somewhat against them. The mechanic was mainly hating on the additional weight of ebikes. He told me about how it will cause quicker wear of brakes pads and discs as well as tires. Then he went into safety. He told me an e mountain bike, with its 50-70lbs of weight will stop a lot slower than a 30lb analog bike. Hence, analog bikes are safer?

I searched online for any data on bicycle braking and average distances from 25 to 0 or 15 to 0. I wanted to see what they were averaging and then try to see how my braking compared. I couldnt find anything. Has anyone seen data on what bicycle stopping distance are? Ebikes? I think it would be good to know, especially when deciding on following distances from other riders or even cars.

 

[indianajo]

I can stop from 30 mph with a load of groceries in about 10'. Not my average stopping distance, as when I do that I fall off the seat and feet come off pedals & hit the pavement. But important to know with deer crossings (streams) at the bottom of the hills I roll down. Deer are as stupid as rabbits. Gross weight 330 lb, 160 mm mechanical disks, Kenda knobby 2" tires. Bike + panniers + double leg kick stand 75 lb.
Yeah, I replace front pads every 4000 miles. Whoopie, a $8 problem that takes 45 minutes to do. As pads are sold in pairs, leaves me a set of pads for the next time. Yeah, the rear tire lasts 2000 miles. Big $26 deal. Reason I put the motor on the front, that one lasts 3000.
Bike stores are too much focused on weight, when the real problem is wind. There is no way I'm going to crane my neck like a lycra club rider hunched over drop bars; Mother fractured a neck disk sitting wrong & I'm built just like her. She was in pain every second of the rest of her life. If I tried to stop in 10' from 30 mph bent forward like that I'd probably hit my head on the pavement. Look at the guy who hit a tree in the Brazil summer olympics. Didn't that bike have brakes?
BTW my reaction time is 56 ms, tested with a co-worker & a 4 month old tek 477 memory scope. On the Army reaction time brake tester, I had to wait for the machine to get ready for me, as when I did it as fast as possible the machine was telling the operator that I put the brake pedal down before operator initiated the test.

 

[Nova Haibike]

He told me an e mountain bike, with its 50-70lbs of weight will stop a lot slower than a 30lb analog bike. Hence, analog bikes are safer?

Using that logic, loaded touring bikes are not as safe as stripped-down racing bikes, and fat people are not as safe as skinny people.

 

[AHicks]

I was at my LBS getting my cassette replaced. Said LBS does not sell ebikes and is somewhat against them. The mechanic was mainly hating on the additional weight of ebikes. He told me about how it will cause quicker wear of brakes pads and discs as well as tires. Then he went into safety. He told me an e mountain bike, with its 50-70lbs of weight will stop a lot slower than a 30lb analog bike. Hence, analog bikes are safer?

I searched online for any data on bicycle braking and average distances from 25 to 0 or 15 to 0. I wanted to see what they were averaging and then try to see how my braking compared. I couldnt find anything. Has anyone seen data on what bicycle stopping distance are? Ebikes? I think it would be good to know, especially when deciding on following distances from other riders or even cars.

There's 2 thoughts here. The first is to totally disregard comments from people like the one you were listening to without first checking them out. Glad to see you're doing that.

The second is who cares what the books say? This is your butt that's on the line. Samples will be all over the ball park, with different brake types, tires, and of course COMBINED rider and bike weights. The plan is to ride within YOUR limits after figuring out about what they are. Even then there are tons of variables, like how long did it take you to figure out you need to be on the binders HARD and right now? Are you on wet leaves or grass, or dry pavement?

My point is, there's not much certainty available here. There's too many variables, including your experience, the condition of your bike, the surface you are on, etc, etc, etc.

 

[rich c]

A good reason why manufacturers put large diameter rotors and hydraulic brakes on eBikes instead of rim brakes.

 

[EbikeTestLab]

I've only tested four bikes (more coming in the Spring hopefully) but they all differ in how quickly they stop and the most effective method for emergency braking. And yes, it will vary be rider so one should practice on their bike to know how to stop quickly. You can read about how I do the braking tests here: https://ebiketestlab.com/braking/


Magnum Metro+: The rear wheel lifts under heavy use of the front brake much like a sporty motorcycle. Stopping distance from 25 mph: 42.9 feet

Faraday Cortland: due to the cruiser style and more laid back bars, the rear wheel doesn't fully lift so both brakes should be used. Distance from 20 mph: 29.5 feet

Ancheer Mountain Bike: Rear wheel lifts like the Metro+, distance from 20 mph: 33.2 feet with severe brake fade so the distance keep getting longer as the rotors and pads get hot from repeated use (imagine braking quickly after using the brakes down a long hill)

Revolve RoughRider (long wheelbase fat tire bike): Super stable due to long wheel base and large tires, essentially one can pull both levers pretty hard without locking anything up and it stops quickly given it's weight. Distance from 20 mph: 31.6 feet.

What really matters is that you practice emergency stops on your own bike as they all behave differently. This also varies with conditions so get out there and practice a few hard stops every month or so.

 

[Ebiker01]

203mm Shimano Ice Tech rotors front and back. Can Stop instantaneous if needed.

 

[EbikeTestLab]

I'll try to go out on my Cannondale gravel bike when the weather cooperates and see how quickly I can stop with a regular bike (still has hydraulic disc brakes though). That would be an interesting data point. My hunch is that it's no quicker to stop from 20 mph than the ebikes I've tested.

 

[fooferdoggie]

203mm Shimano Ice Tech rotors front and back. Can Stop instantaneous if needed.

isn't that when you hit the pavement head first?

 

[J.R.]

I was at my LBS getting my cassette replaced. Said LBS does not sell ebikes and is somewhat against them. The mechanic was mainly hating on the additional weight of ebikes. He told me about how it will cause quicker wear of brakes pads and discs as well as tires. Then he went into safety. He told me an e mountain bike, with its 50-70lbs of weight will stop a lot slower than a 30lb analog bike. Hence, analog bikes are safer?

I searched online for any data on bicycle braking and average distances from 25 to 0 or 15 to 0. I wanted to see what they were averaging and then try to see how my braking compared. I couldnt find anything. Has anyone seen data on what bicycle stopping distance are? Ebikes? I think it would be good to know, especially when deciding on following distances from other riders or even cars.

Sounds like a bit of confirmation bias with that LBS. There's a lot to consider, as others have said. Ebike tech has actually helped bicycle technology and performance.

The Technological Effects of eMTB on the MTB World

I've read numerous accounts of pro mtb riders switching out various MTB components for eMTB designed components. This due to performance; performance that outweighs the weight gain. https://m.pinkbike.com/news/opinion-e-bikes-are-breeding-the-components-riders-want.html Brakes, driveline...

electricbikereview.com

 

[The duke]

I've only tested four bikes (more coming in the Spring hopefully) but they all differ in how quickly they stop and the most effective method for emergency braking. And yes, it will vary be rider so one should practice on their bike to know how to stop quickly. You can read about how I do the braking tests here: https://ebiketestlab.com/braking/


Magnum Metro+: The rear wheel lifts under heavy use of the front brake much like a sporty motorcycle. Stopping distance from 25 mph: 42.9 feet

Faraday Cortland: due to the cruiser style and more laid back bars, the rear wheel doesn't fully lift so both brakes should be used. Distance from 20 mph: 29.5 feet

Ancheer Mountain Bike: Rear wheel lifts like the Metro+, distance from 20 mph: 33.2 feet with severe brake fade so the distance keep getting longer as the rotors and pads get hot from repeated use (imagine braking quickly after using the brakes down a long hill)

Revolve RoughRider (long wheelbase fat tire bike): Super stable due to long wheel base and large tires, essentially one can pull both levers pretty hard without locking anything up and it stops quickly given it's weight. Distance from 20 mph: 31.6 feet.

What really matters is that you practice emergency stops on your own bike as they all behave differently. This also varies with conditions so get out there and practice a few hard stops every month or so.

The LBS guy was telling me about how road bikes go from 15 to 0 in under 10 feet and that on my ebike, my average speed was much faster and my average stopping distance was triple that. Interested to see how right he is.

 

[The duke]

203mm Shimano Ice Tech rotors front and back. Can Stop instantaneous if needed.

The LBS guy pointed out my 180mm disc brakes. He showed me the blackening of the brakes. He also spun the wheel and let me hear the slight sound it made at the point the disc was hitting the caliper. He said that was the excess weight of my bike causing warping of the disc under heavy braking. He suggested I get 203mm discs immediately plus extenders to make the calipers match up. He told me ebike makers haven't woken up to the fact that they cant or shouldn't be using traditional bike parts on ebikes, which he feels are more motorcycles

 

[tomjasz]

A smarter than average rider will get a friend and do some MSF drills and determine exactly what the stopping distance is. 2" tire, 30PMH, and ten feet seems a huge exaggeration based on my testing my bikes.

While this is about motorcycles, the principles remain the same. As ebikes get faster, even countersteering begins to come into play.

https://www.msf-usa.org/downloads/BRCHandbook.pdf

 

[Ebiker01]

isn't that when you hit the pavement head first?

W/o having the experience of doing it properly: instantly moving your body weight 10-15inches towards the rear wheel while also lowering it 5-7inches , yes the Effect is as you had described it.

 

[Ebiker01]

He told me ebike makers haven't woken up to the fact that they cant or shouldn't be using traditional bike parts on ebikes, which he feels are more motorcycles

Yes that is true . Top ebikes have 203rotors and 500$ Brake systems(Măgura mt/5, Shimano Saint..).
The ICE tech Rotors are very good.
Ask his help to get the right caliper extender , you won’t find that easily.

 

[slayer1962]

i agree if i am going 28 mph on my e bike and that is faster than i would pedal on my regular bike i should use a greater following distance. ( just like any car or motorcycle )
so if you want to be careful never exceed 15 mph on any bike there you go lol

 

[Alaskan]

Four caliper disk brakes do not stop you any faster in a sudden emergency braking situation than two caliper disk brakes, using the same size rotors. What they do is build up less heat. This reduces fade due to pad and rotor overheating. This is important on extended downhill riding on mountain bikes which are heavier, spend more time going down hill in extreme conditions are allowed to accelerate and then braked hard repeatedly in downhill riding. Emergency stopping normally does not occur when the brakes are already overheated from constant, hard downhill use.

 

[Cowlitz]

Using that logic, loaded touring bikes are not as safe as stripped-down racing bikes, and fat people are not as safe as skinny people.

My thoughts exactly. When I have pointed this out, there is silence. There is no way that 30 pounds of human weighs less than 30 pounds of bike. More STEM training needed?

 

[Alaskan]

My thoughts exactly. When I have pointed this out, there is silence. There is no way that 30 pounds of human weighs less than 30 pounds of bike. More STEM training needed?

And then there is the question how much does added weight increase traction. I presume there must be a crossover point where traction does not increase proportional to the added weight be there also must be a point where less weight = less traction = longer braking distances. Of course traction depends on other factors besides weight, like tire tread, compound, contact patch size, road surface, wet - dry - snow - ice - sand - gravel - oil spill

 

[tomjasz]

I have 26" discs, they're called rims. Of course high power bikes benefit from disc brakes, but there's no doubt in my experience that properly setup rim brakes are better than budget hydraulics. I'll stand my Tektro rim brakes with KoolStop eBike pads up against any disc or hydraulic on any $1500-$2000 wonder bike.