250 watts just isn't enough. It can help you carry a load or it can help you up a hill, but not both. I wouldn't even bother with an ebike at that wattage. 500 (like in NSW) is a much more sensible maximum.

It's especially true given that wattage isn't the real issue. Top speed is the issue and that can be capped independent of wattage.

[–] Zagorath@aussie.zone 5 points 1 day ago (1 children)

Yeah I think NSW's approach is pretty good. As you say, 250 W is a bit limited with heavy loads up hills. To put this into perspective, on my analogue bike, up one of the steepest hills I've ever climbed in Brisbane, I do about 400–500 W for about 20 seconds. Ebikes are all required to be pedal-assist, so let's assume a baseline of 100 W from the cyclist's legs (about what a casual cyclist who just wants to cruise along would do), plus the 250 W maximum output. That's 20 seconds where they're having to pedal extra hard, even if their total load (including bike, rider, and water) is comfortably under 90 kg. Make that a serious cargo bike (++kg) loaded with shopping, sports equipment, or kids (+++kg) and you're likely going to end up putting out more power with your legs than I do on my analogue bike even after you account for your motor assistance.

NSW also has a rule requiring the motors to smoothly taper their power. So at the 12 km/h I climb this particular hill at, you might get 400 W of assistance, but if you're getting up to 22 km/h it might be just 100 W[^1]. Basically, it naturally self-corrects for any risk that might be associated with higher power at higher speeds. EN15194, otoh, is 250 W flat. It allows peaking above that amount for a short time, but from what I can tell it's not clear how long that time is, or how it works in practice on compliant bikes.

A counterpoint to this take would be: the hill I'm describing is extremely steep, and chosen in part because it's steep. I'd go a different, easier route, if I wasn't on a training ride. And 90% of the time, most utility cyclists will have options that avoid climbs that steep. And also that perhaps it's not unreasonable to expect ebike users to put out more effort on hills than they do on the flat. Personally I find both of these arguments convincing enough if used against even higher power limits, but not convincing enough for me to oppose 500 W. Especially since I'm also in favour of increasing the speed cap from 25 km/h to 30 or 32 km/h (20 mph), since that's the speed I feel I can comfortably reach without too much effort on the flat, on an analogue bike.

[^1]: I made no attempt to actually do the maths on this. And I'm not sure if it's meant to be a linear drop-off or if some curve is applied anyway.

[–] ada@piefed.blahaj.zone 3 points 1 day ago (1 children)

See, that sounds absolutely perfect. Like you, I'd prefer 30 to 25, but whatever, that's not a hill I need to die on. 25 does the job just fine too.

And I love the fact that the wattage reduces as your speed amps up, because that means you get the most power when you need it, when carrying loads, hitting hills etc.

I'd be quite ok with Australia adopting NSWs standards, because at that point, my ebike is still a viable alternative to car.

But at 250W it's not.

[–] Zagorath@aussie.zone 1 points 15 hours ago

I think I take a slightly softer position than you do, because in my view 250 W is a viable alternative to a car the majority of the time. It becomes a problem on very steep hills when carrying heavy loads, but most people are not doing that very often, and a better cycling network buildout (which is always my first priority) would reduce the need for it even further, if people had safe convenient routes around hills that didn't force them up and over unless either they want to take the shorter, harder route, or their destination is actually on the hill.

But I do still ultimately agree with you. Ideal world, we'd change it to allow them. It's more accessible to more people, and I cannot see much disadvantage, if the speed regulators work correctly.

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