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DJI announces an electric mountain bike drive system

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Re: DJI announces an electric mountain bike drive system

#51

Earlier quoted context omitted.

Legal limit in USA is 750 watts, legal limit in UK is 250 watts. Competition on power output is illegal. I have a BBSHD which can be trivially programmed to 1500w output (likely the same as your Luna cycle without a custom controller) and it’s great. It is widely regarded that there is no enforcement of power limits, but manufacturers can’t really advertise illegal power limits for sale. Many high power ebike enthusi…

> Many high power ebike enthusiasts (for example “High Voltage DIY Electric Bikes” channel on YouTube) argue that these low legal power limits actually make e-bikes less safe, as you need a good 2-3kw to actually ride with the flow of traffic. At US or worse UK power limits, you don’t get enough of a boost for that and you’re more likely to get hit from behind. Those "High power ebike enthusiasts" are actually "small…

Maybe technically correct, but these are being sold as bicycles. I think the biggest distinction between most (but not all) high powered ebikes and electric motorcycles is that most of the ebikes can be powered by pedaling (except bikes like the Sur Ron).

We can make a legal category for "electric motorcycles with pedals" or we can call them high powered electric bicycles. I don't care so much what we call them as long as we recognize that this type of vehicle is extremely valuable in fighting climate change and building more walkable cities with less need for automobile infrastructure. If everyone could legally ride a 2kw ebike around town with some nice panniers or a rack for cargo space, so many automobile trips could be eliminated.

> I'm fine with a separate class of regulations allowing higher power, but only if those vehicles are easily disallowed from bike trails. If the goal is to ride around with cars in traffic all day, it shouldn't be a problem to be banned from bike trails.

When you say trails, I could agree on dirt trails where erosion and environmental damage is an issue. But as we build out better bicycle infrastructure around the country, we have more and more dedicated paved bike paths. It would be absurd to me if bikes like my 1.5kw ebike were barred from paved bike paths. And note, it already is! Most of the paved bike paths around Oakland and Berkeley are legally restricted to class 2 ebikes. My bike is beyond class 3, and so illegal both generally and on these paths. But I don't think it should be! I have been bicycling for almost 40 years, so I am extremely respectful of other people and I don't want to blow past anyone. Maybe there need to be more fine grained laws around etiquitte, or maybe we need to expand our notion of bike paths to include 3kw ebikes. There must be some middle ground between surface streets with 4000lb vehicles and bike paths that are only for low powered or human powered bicycles.

But my broad point is, these vehicles are extremely important to a world with reduced carbon emissions. They are much more useful than a regular bike (which I also ride quite a lot) for transportation purposes, and so better as a car replacement. They take less resources and emissions to produce, they use less energy to move a person, they are safer for pedestrians than automobiles, appropriate infrastructure takes up less space, etc etc etc.

The attitude of "that's a motorcycle! you had better keep that as far away from me as possible" is a negative-focused view on what can be an extremely transformative technology.

I know there are assholes and irresponsible people, and actually a good friend of mine broke their leg in an ebike-on-ebike collision in the UK on a legal 250w ebike, so I understand that injuries can still happen. And I absolutely do not want assholes blowing past old ladies or parents walking their kids in strollers.

But we MUST consider the real value this new type of machine has to offer, and genuinely take time to consider how they should be used. The knee-jerk claim that it is just a motorcycle is missing that in reality they are a new class of vehicle. Similar to a bicycle and similar to a motorcycle, but lighter than one, easier to handle, and I would argue much more useful.

So sure, let us create regulations around them. But let us make sure we allow them on appropriate bike paths, and build the right infrastructure to take advantage of such a useful new type of machine.

Re: DJI announces an electric mountain bike drive system

#52
post #46
post #13

> The integrated DJI Avinox electric power assist system leverages DJI's cutting-edge technologies in both software and hardware design, offering 850 W of peak power (250 W nominal power) in an ultra-light body of 19.2kg This is most unimpressive. I have an 2019 3000w LunaCycle e-mountain bike (based on the Giant Anthem) with similar drive system weight specs, which includes the ginormous 40ah battery. Why can't DJI…

Your LunaCycle probably weighs > 70lbs! The Amflow PL bikes lists in the press release as 43lb which isn't "revolutionary" but 850W and 600Wh battery is way more than the other really light MTBs. And those other ones are really expensive. I'm looking forward to seeing price. I wish they had shared some specs regarding noise, it sounds like they have put some effort into optimizing that as well. I like my 1500W LunaCy…

It's a little under 50lbs in total I think. Something like 48-52lbs if memory serves. By the way, it wasn't easy standing on a scale holding the bike, but when it was I felt this to be very necessary, haha.

But the numbers make sense, without the battery and motor, the bike should be around 15 pounds, which leaves ~35 lbs of battery + motor.

*p.s. Apparently I was mistaken up in the thread - the battery pack is only 21AH, not 40.

Re: DJI announces an electric mountain bike drive system

#53

Earlier quoted context omitted.

Approximately no one is paying thousands of dollars to shave grams off an eMTB. There is a small but visible group of people doing that for road bikes and a much smaller group of people doing that for non-electric mountain bikes. There's probably some weirdo out there doing it for an electric mountain bike but they're probably more of a "decorative expensive bike purchaser" than an "actual trail rider".

There are carbon fiber E-bikes, perhaps it’s “few” but there are people paying to have a more light bike since the extra weight up and down hill isn’t as fun

The weight difference between equivalent carbon and aluminum eMTBs is generally around a kg, but the argument for carbon MTBs has mostly shifted away from weight. While carbon fails more catastrophically than aluminum, it's harder to hit the failure point and it's less susceptible to stress fractures. It is also generally argued that carbon is both more dampening and stiffer in the places you want stiff, but it is very hard to tell how real that is.

Re: DJI announces an electric mountain bike drive system

#54

Earlier quoted context omitted.

Legal limit in USA is 750 watts, legal limit in UK is 250 watts. Competition on power output is illegal. I have a BBSHD which can be trivially programmed to 1500w output (likely the same as your Luna cycle without a custom controller) and it’s great. It is widely regarded that there is no enforcement of power limits, but manufacturers can’t really advertise illegal power limits for sale. Many high power ebike enthusi…

> Many high power ebike enthusiasts (for example “High Voltage DIY Electric Bikes” channel on YouTube) argue that these low legal power limits actually make e-bikes less safe, as you need a good 2-3kw to actually ride with the flow of traffic. At US or worse UK power limits, you don’t get enough of a boost for that and you’re more likely to get hit from behind. Those "High power ebike enthusiasts" are actually "small…

Thanks for the pile-on, but this is completely irrelevant to what I was posting about. The DJI kit is very heavy (in KG) to deliver a comparatively puny amount of power. That is the interesting point, not the legality of an e-bike I purchased 5 years ago and haven't had any trouble with. Just saying.. be cool.

P.s. parent has heavily edited their comment to not resemble the original comment. For whatever it's worth, I don't have any particular agenda except to share information. I'm logging off for the evening, because this is peak nonsense.

Re: DJI announces an electric mountain bike drive system

#55
post #49

Earlier quoted context omitted.

> Many high power ebike enthusiasts (for example “High Voltage DIY Electric Bikes” channel on YouTube) argue that these low legal power limits actually make e-bikes less safe, as you need a good 2-3kw to actually ride with the flow of traffic. At US or worse UK power limits, you don’t get enough of a boost for that and you’re more likely to get hit from behind. Those "High power ebike enthusiasts" are actually "small…

Well put. I wouldn't want to ride with my kids with a 3000w bike breezing pass me in the bike lane at 45km/h

Did you know lots of people can ride a road bike under 100% human power at 27MPH+ (45kph?)? Parent comment doesn't align with commonly observed reality.

Iron Man participants regularly ride at an average speed of 24mph+ continuously for 112 miles in extremely harsh conditions (Hawaiian heat).

Also, over the course of many thousands of miles I've never observed any cyclist riding past vulnerable children at these speeds. What is the problem exactly? People going "fast" on a 50lb bicycle with nobody else around? How is this a threat?

Most people aren't out to get you, especially bicyclists.

If you want to direct energy towards something, please send it towards the inconsiderate cars vectoring a 3ton+ vehicle at 25-75MPH even when they see a person in the road ahead. It's sad when a human is struck by a vehicle.

*I usually don't respond to comments like this one but after being hit by a car while I was in the bike lane on Veterans Blvd in Redwood City, CA in 2018, who didn't bother stop (or even notice they'd hit and knocked me down?), it's a bit of a sore spot. The difference between a car and a weapon is what, exactly? Even an overpowered e-bike is nothing compared to any of the tens of thousands of cars who kill and maim cyclists and pedestrians in the U.S.A. annually.

Re: DJI announces an electric mountain bike drive system

#56

Earlier quoted context omitted.

I'd trust their intent to create a good product (rather than aiming for something that will look good enough for just long enough to get you to buy it), their general manufacturing, and even engineering, but with the forces and water/dirt involved, I am not confident they'll succeed in the first few iterations.

> but with the forces and water/dirt involved, I am not confident they'll succeed in the first few iterations. Air isn't perfectly clean or dry, either. I would bet that DJI has some clue as to how to protect the most sensitive components in a way that can survive _lots_ of vibration.

I agree with GP here, even on a city bike the determination water, grease and fine grit have to ingress into totally inaccessible spaces and ruin them from within is relentless. And then it's 10x worse in a mountain bike scenario.

Clearly not unsolvable but I'd wait for some 1 year use reviews before even thinking about it.

Re: DJI announces an electric mountain bike drive system

#57

This is great for the e-bike sector - more competition, more innovation, more options. There is of course a bunch of poo-pooing in an HN thread. The problem with the e-bike sector is a misalignment: what people say they want: a cargo bike, a fixie, a mountain bike, a folding bike, a... etc. what people actually want: a moped that is emotionally and aesthetically a bicycle The audience for a moped that is emotionally…

It's not "emotional", it's "regulation-evading" that people are looking for. They want a moped without registration, license, insurance and all other things that may accompany one depending on jurisdiction. As a result we now have 250 lb "cyclists" doing 25 mph on their 70 lb mopeds with miniscule brakes and tires on the bike-and-hike trails, imposing great danger on themselves and others.

Re: DJI announces an electric mountain bike drive system

#58

Earlier quoted context omitted.

Legal limit in USA is 750 watts, legal limit in UK is 250 watts. Competition on power output is illegal. I have a BBSHD which can be trivially programmed to 1500w output (likely the same as your Luna cycle without a custom controller) and it’s great. It is widely regarded that there is no enforcement of power limits, but manufacturers can’t really advertise illegal power limits for sale. Many high power ebike enthusi…

> Many high power ebike enthusiasts (for example “High Voltage DIY Electric Bikes” channel on YouTube) argue that these low legal power limits actually make e-bikes less safe, as you need a good 2-3kw to actually ride with the flow of traffic. At US or worse UK power limits, you don’t get enough of a boost for that and you’re more likely to get hit from behind. Those "High power ebike enthusiasts" are actually "small…

Trails and bike lanes too. If you want an electric motorcycle - get one, get a license, register it and stay the fuck off the bike paths.

Re: DJI announces an electric mountain bike drive system

#59
post #8

Earlier quoted context omitted.

Actual trail riders mostly do not do this. Source: worked at a bike store. People with a lot of money that treat their bike as something to optimize and not something to ride do this. I'm not saying its wrong, its just another way of being a bike enthusiast, but this type rarely overlaps with serious riders. Training improves performance, not $3000 wheels that shave off 50 grams.

Isn't this about e-bikes? Do people generally train on e-bikes? It feels that these two would be distinct sets.

I don't think people with e-bikes even pedal into the orange zone. It's more of exercise theater, to borrow a term. HOwever, I do hope e-bikes start to overtake cars as modes of transportation in temperate climates.

Re: DJI announces an electric mountain bike drive system

#60

Earlier quoted context omitted.

> but with the forces and water/dirt involved, I am not confident they'll succeed in the first few iterations. Air isn't perfectly clean or dry, either. I would bet that DJI has some clue as to how to protect the most sensitive components in a way that can survive _lots_ of vibration.

I agree with GP here, even on a city bike the determination water, grease and fine grit have to ingress into totally inaccessible spaces and ruin them from within is relentless. And then it's 10x worse in a mountain bike scenario. Clearly not unsolvable but I'd wait for some 1 year use reviews before even thinking about it.

> but I'd wait for some 1 year use reviews before even thinking about it.

This is a solid strategy for just about any new company/product-line.

Even with years of experience in drones, DJI had an insane amount of (mostly positive) change between the first and second generation of mavic drone.

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