I only have a little.
One important thing is that the instances of fire largely stem from two factors (really mainly one), those being 1) poorly built chargers and 2) leaving the battery connected to the charger after charging is complete. It's mainly just the charger, because a properly designed charger will cut off current to the battery once the charge is complete. Also, different designs configure the charge cycle differently. The main reason people use inadequate chargers is price - a proper charger will always, at least currently, be expensive, lower end being in the range of $100.
Also, cheaper ebike manufacturers often do not ship quality chargers with their bikes, and the consumer doesn't even know the difference or subsequently have the ability to compensate.
Other bits of wisdom:
Mid-drive kits are nice for traditional mechanics because they change very little of how a traditional bike is assembled and functions. The exception to the advantages being that if your chain snaps, you are dead in the water just like on an normal bike, but unlike on a normal bike, you might be hauling a trailer, or 30lbs of groceries uphill. Not fun. Another advantage of mid-drive motors is that your motor has access to the full range of gearing possibilities for the rear hub, which means the motor (and battery) can benefit from the same kinds of gearing advantages that your muscles do. Saves wear and battery life; I get way more range and performance out of my mid-drive ebike than I do from my wheelhub ebike.
Wheelhub motors, the other option, require non-standard spoke sizes, and in order to be structurally sound, also require reinforced dropouts in the frame, due to the high torque involved. Wheelhub motors also force the center of gravity to the rear, where a lot of the rider weight is centered anyway, making for poor handling unless the overall construction compensates for it. This is exacerbated when the battery is mounted over the rear wheel. One advantage is that on a wheelhub motor ebike, the chain can snap and you still have drive, though snapping is less likely in this case since it isn't used for motor drive.
Front wheelhub motors are a terrible idea unless they are very small, as forks were never designed to bear sudden acceleration forces, especially with electric motors being especially high-torque. Also, front dropouts are usually more minimal, and therefore weaker than rear.
Suspension is also important to have on the higher-speed bikes. Hitting a pothole at 2mph on a road bike with narrow tires and the extra weight of a motor and battery (and whatever else you're carrying because you have the extra power of the motor and battery) is a dangerous and extremely uncomfortable experience. It can increase the likelihood and severity of repetitive stress injuries. Wide tires are a minimum requirement for long term riding.
Off the top of my head, the last thing is GEOMETRY. Bicycle geometry is generally not designed for constant high speed handling in traffic; most road-spectrum frames, including gravel, randonneur, cyclocross, etc., have way too steep of a head tube angle to maneuver safely at 20-30mph. These angles (notwithstanding the rake, of course) are made for precision moves at low speeds, where safe high speed handling requires a great deal of experiences and control. Think of every motorcycle head tube you ever saw - nowhere near vertical. So, a frameset really has to have been designed appropriately for it's intended sustained speeds.
It's disturbing how many ebikes out there come from the manufacturer advertising 25+mph speeds while still featuring more or less normal bicycle geometry.
There's other stuff about voltages and battery mounts and component choices and software too, but a lot of that falls more into consumer/enthusiast types of data.
~cyclista Nicholas
On 2023-02-15 23:32, Darin Wick via Thethinktank wrote:
Sounds like e-bikes would be a good workshop topic for Bike!Bike! and/or Bike!Bike! Everywhere!.
Sub-topics would probably include:
- Overview (common types of e-bikes, advantages/disadvantages, and
associated use-cases)
Safety (weight, electrical, fire)
Insurance
DIY or self-installed systems (installation, maintenance, and repair)
Commercial systems (training & licensing, maintenance, and repair)
Resources for learning more & to share with patrons who have
questions about e-bikes
That's a lot of ground to cover, and much of it requires special knowledge, so maybe it would be a general discussion with a panel of topic-experts? I can speak a bit on self-installed hub motor systems and might be able to get a friend with experience in Bosch systems to participate.
Anyone else have relevant expertise that they could share?
-Darin
---- On Fri, 10 Feb 2023 19:54:41 -0800 Alejandro Manga Tinoco via Thethinktank thethinktank@lists.bikecollectives.org wrote ---
I forgot to mention that Worcester Earn-a-Bike is a partner organization for the e-bike project, and they received some grant money from it.
On Fri, 10 Feb 2023 at 22:52, Alejandro Manga Tinoco mailto:alejandromanga@gmail.com wrote:
In 2018, during the general assembly of l’Heureux Cyclage - the French network of bike kitchens - which is an association, similar in kind to a 501 c3 in the US, voted in favor of a motion to forbid repairing e-bikes in the member kitchens. Then in 2020 or 2021, we backtracked, and it was left to the choice of the individual organizations. Some of the most radical kitchens are strongly against on principle that it requires and depends on technologies and resources that predatory towards the environment ( lithium extraction), and also because it encourages speed, which is against the idea of slowing society down, and favoring low-techs like mechanical bikes which have much less on an impact.
Though privately, some members that have moved to the countryside will let you know that they bought a car because not even an e-bike when you are located in a place where everything is 20km (15 miles) away.
As noted by Claire, some kitchens have decided to accept e-bikes, and some have started training their mechanics in the skills necessary to repair e-bikes. The big problem is the software, which on one hand is proprietary, and on the other it requires another set of skills to be dealt with. But I think that right now in France 60% of all new bikes sold are electric, so the question clearly is not going away.
And here in Worcester, MA, where I am currently living, MassBike – the organization that lobbies at the state level has a program where 100 e- bikes were given to low-income people as part of a program to estimate the reduction of the carbon footprint, and also do a follow-up from a mobility justice perspective. I am most likely going to be doing that follow-up myself, with the university that I work for here (WPI).
One of the political goals of the project is to prove that e-bikes are a solution in a suburban setting, where 60% of the people in the US live, so that the state of Massachusetts passes a law subsidizing the buying of bikes. The other one, is to create arguments to encourage policies that have a mobility justice perspective, to lobby for better policies ( not only in terms of infrastructure) in the city of Worcester. Personally, I think that given the urban form most US places have, the best shot there is to get some people out of their cars, is to have them ride e-bikes. So I am all for that.
Alejandro
On Fri, 10 Feb 2023 at 19:01, tomharrison00--- via Thethinktank mailto:thethinktank@lists.bikecollectives.org wrote:
Thanks for this valuable thread about the increasingly emerging E-bike issue.
Tom Harrison (past board member) Third Hand Bike Co-Op, Columbus
Sent from my iPad
On Feb 10, 2023, at 8:59 PM, Andy Ballentine via Thethinktank
mailto:thethinktank@lists.bikecollectives.org wrote:
Hi --
How are bike co-ops dealing with e-bikes? We are all-volunteer at
the Bicycle Co-Op of Williamsburg (Virginia). We have several very fine mechanics, but none of us is expert in the motors and batteries of e-bikes, and we don't know whether we should accept them as donations or sell them. I'd be interested in others' experience and policies.
Thanks --
Andy Ballentine ____________________________________
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