Injured ebike Share riders (of Citibikes) 'lawyering up'

Mike's E-Bikes

Well-Known Member
#1
Even a Citibike employee claims 'cheap ebikes ' and 'quick fixes ' and said he 'knew ' this was gonna happen.

https://www.nydailynews.com/new-yor...0190421-5fq26lrlbvbihj2re7zpqhiepi-story.html

The primary reason for posting this, is not to slam Citibike or others like Lyft here in Chicago who yanked these ebikes after the accidents, but to let people know that the front brakes on these ebike share bikes, are very different than nearly any consumer sold ebike. They are using a rather odd front enclosed 'drum' brake, that Shimano is claiming that these firms improperly applied without using what they term a 'power modulator.' More than likely this power modulator, is similar to the function of ABS that we know about for cars. It would make sense that it would 'pulse' the brakes rapidly to prevent brake and wheel from locking up too suddenly. (And throwing the rider over the handle bars - not good).

On regular ebikes you either see disc brakes or caliper style brakes. Not these drum brakes.

The injured riders sound like they have a very serious claim, and the suddenness of the stopping using the brakes, seems really unusual.

It's too bad this happened and let's hope there is not too much negative fall out that scares would be ebike buyers from moving ahead.
 
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Timpo

Well-Known Member
#2
These rental bike businesses are relatively new in the US.

They have been operating a while in Europe or Asia.. I could not find any cases of lawsuit like this.
I wonder what the US companies are doing wrong. Not maintaining bikes properly?
 

Dewey

Well-Known Member
#3
I've read a report from a DC rider who nearly went over the handlebars 3-4 times during one ride on a CaBi+ (same design as CitiBike & Ford GoBike ebikes). It was reported in the Post that Jump & Lyft bikeshare ebikes use the Shimano BR-C6000-F front roller brake. Reportedly heat dispersal isn't good and the design requires frequent regreasing - one commenter on another forum reported if roller brakes "aren't relubed regularly enough, they tend to lose braking power, unless the lever is pulled quite hard, at which point they 'grab' and brake sharply." Sheldon Brown reported mechanic Jeff Bertolet as saying "The life cycle of a (roller) brake goes something like this: add small amount of grease (pea size amount) in addition to factory grease when installing a new brake. After some months, the grease is washed away by rain. The brake is now dry and has poor or nonexistent modulation which locks the wheel with the slightest pressure on the lever." This explanation jibes with the reported accidents. Sheldon Brown disliked brake "power modulators", and I am not a lawyer, but they appear to have been recommended by Shimano to provide a fail-safe in the event of the known problem. CaBi bikeshare pedal bikes use roller brakes so presumably they were chosen by Lyft/Motivate for their bikeshare ebike for common servicing economy. I haven’t read of this being a problem with bikeshare pedal bikes but I don’t know if those have power modulators fitted, or if it’s just not a good brake for a heavier hub motor wheel. A bigger problem as reported in the Post article is that Uber experienced this problem and fixed their Jump bikes, presumably fitting power modulators, but didn’t inform Lyft.
 
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Mike's E-Bikes

Well-Known Member
#4
I've read a report from a DC rider who nearly went over the handlebars 3-4 times during one ride on a CaBi+ (same design as CitiBike & Ford GoBike ebikes). It was reported in the Post that Jump & Lyft bikeshare ebikes use the Shimano BR-C6000-F front roller brake. Reportedly heat dispersal isn't good and the design requires frequent regreasing - one commenter on another forum reported if roller brakes "aren't relubed regularly enough, they tend to lose braking power, unless the lever is pulled quite hard, at which point they 'grab' and brake sharply." Sheldon Brown reported mechanic Jeff Bertolet as saying "The life cycle of a (roller) brake goes something like this: add small amount of grease (pea size amount) in addition to factory grease when installing a new brake. After some months, the grease is washed away by rain. The brake is now dry and has poor or nonexistent modulation which locks the wheel with the slightest pressure on the lever." This explanation jibes with the reported accidents. Sheldon Brown disliked brake "power modulators", and I am not a lawyer, but they appear to have been recommended by Shimano to provide a fail-safe in the event of the known problem. CaBi bikeshare pedal bikes use roller brakes so presumably they were chosen by Lyft/Motivate for their bikeshare ebike for common servicing economy. I haven’t read of this being a problem with bikeshare pedal bikes but I don’t know if those have power modulators fitted, or if it’s just not a good brake for a heavier hub motor wheel. A bigger problem as reported in the Post article is that Uber experienced this problem and fixed their Jump bikes, presumably fitting power modulators, but didn’t inform Lyft.
Roller brakes ? On bike share bikes ? On EBIKE bike share bikes ? Recipe for disaster. It makes zero sense to use those. I can't believe anyone is still selling that technology. It was irresponsible of Shimano to sell rollerbrakes for an ebike, especially applied to a front wheel.
 
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Dewey

Well-Known Member
#5
Roller brakes are used on bikeshare pedal bikes apparently without the problems experienced, though I've ridden some older worn out CaBi pedal bikes with spongy brakes they're generally pretty good at rotating them out of the active fleet when problems are reported. Roller brakes are popular on Dutch cargo pedal bikes like Workcycles, Bakfiets, Bertus, etc. though retailers usually offer an upgrade to a Magura hydraulic rim brake if you opt to convert your cargo bike and most of those conversions use a mid-drive motor, I don't recall ever seeing a Shimano roller brake on a hub motor and it is a disturbing coincidence that these problems occurred on two different models which suggests this is a dangerous combination without the power modulators Shimano recommend. That Shimano were apparently happy to sell the brake without power modulators is a problem, but the larger problem the Post article highlights is the lack of regulatory oversight, or at least a channel for sharing safety data between bikeshare operating companies. The Post already reported the CPSC under the current administration is taking a step back from actively pursuing recalls against certain corporations. How Uber, Lyft, and Shimano, respond to correct the problem and compensate the injured riders will indicate how seriously they take their safety responsibilites aka how much they feel they can get away with.
 
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Timpo

Well-Known Member
#6
Roller brakes ? On bike share bikes ? On EBIKE bike share bikes ? Recipe for disaster. It makes zero sense to use those. I can't believe anyone is still selling that technology. It was irresponsible of Shimano to sell rollerbrakes for an ebike, especially applied to a front wheel.
What the the heck is roller brake?
 

Dewey

Well-Known Member
#9
They are older technology, cars used to use them exclusively until disk brakes came along. Some pedal bicycle manufacturers swear by them, most traditional Pashley utility and step through pedal bikes have them. I believe the biggest problem is brake fade so I have read moped riders prefer the larger 90mm SA drum brakes over the standard 70mm version.
 

Timpo

Well-Known Member
#10
They are older technology, cars used to use them exclusively until disk brakes came along. Some pedal bicycle manufacturers swear by them, most traditional Pashley utility and step through pedal bikes have them. I believe the biggest problem is brake fade so I have read moped riders prefer the larger 90mm SA drum brakes over the standard 70mm version.
I know what drum brakes are, but I had never heard of roller brake. Unless you're saying cars used to have roller brakes?
 

Dewey

Well-Known Member
#11
I know what drum brakes are, but I had never heard of roller brake. Unless you're saying cars used to have roller brakes?
No, I was referring to drum brakes on cars. Roller brakes appears to be Shimano specific. I've also seen another weaker type of drum brake on electric scooters and cheaper Chinese ebikes, eg the rear brake on the Nakto City, refer to 'band brakes'.
 
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#12
Why would they put them on the front wheel. I remember a Shark Tank episode where someone created a braking system that would automatically engage the rear brake before applying pressure to the front, eliminating the chance of flipping over. That would be ideal for the inexperienced citibike rider.

I removed the video (no advertising) but it's called the surestop braking system.
 
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