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Comment by jhbadger | Hacker News Reader

In California, where this targeted, the maximum legal speed even on a freeway is 70mph.

Top speed might not be a relevant concern here. How long does it take to get to 60mph with 27 horsepower, and/or is it even possible on a grade?

This power is on par with a riding mower at Home Depot.

Must be quite fast, as for any electric motor.

From the manufacturer website the car is listed as 45 kW, which is 60 horsepower, not 27.

Looking at the power-to-weight ratio, it's on par with the cheapest version of the Renault Zoe, so it should actually be fairly useable on highways. The Zoe does 0-60 in 13 seconds, which is definitely not fast, but it's not unusably slow either.

Probably the collision safety would be what stopped me from taking this thing on the highway.

Hmm. They list that as the motors “rated” power which seems to beg the question of why that qualification is merited. Is the battery and motor controller capable of delivering the 45kw the motor is rated for?

Motortrend says “less than 30hp” and CNN says 27.

https://www.motortrend.com/news/2021-kandi-model-k27-k23-ev-...

https://www.cnn.com/2020/08/26/success/kandi-10000-electric-...

I couldn’t find any other citations of output power.

data point: i've been in a zoe on a highway and it didn't have any issue getting to 140km/h (~86mph).

Electric horsepower curves are different from ICE horsepower. [1] ICE engines typically only put out peak horsepower at higher RPMs. A Honda Fit has a peak horsepower of 128. However at 2000 RPM the Fit only has 27HP, like this Kandi K27. [2]

At similar gross weights the Kandi with the pedal to the metal will accelerate like a Honda Fit driven casually or a truck with a trailer. Enough for 55 mph highways, city streets, or the slow lane of a 65 mph Freeway.

[1] https://auto.howstuffworks.com/how-does-horsepower-figure-in....

[2] https://www.automobile-catalog.com/curve/2018/2566010/honda_...

I own a Fit. The only time you're at or below 2000 RPM in a Fit is during cruise, deceleration, or creeping along at 15mph in school zones on flat ground. Just going up my quiet residential street with a slight grade at 20mph, I'll run it out to ~3500rpm.

Also, that torque curve isn't as relevant as it used to be -- a new Fit has a CVT, so the engine will continually operate at that peak power RPM when at WOT.

Operating on a grade will have a significant impact on that top speed. You can probably do a 65mph highway in the slow lane as long as the road doesn't have a grade and there is significant merge area.

The first gen Prius actually had this problem in San Fran. In reverse, they only use the electric motor, and it was not strong enough to go in reverse up some hills. It had a 40hp electric motor.

That may be true, but the minimum speed before you are honked at from the car behind is about 60. That also matters.

Only if you're in the left lane, which you shouldn't be unless you're, you know, actually passing someone.

Basically, just pretend you're driving a really tiny semi and you're good to go.

Just for fun I've driven at 55 for a few weeks when I was trying to see how high I can get my mpg number. Every car was passing me, including semis. Even when driving purely in the right lane.

I know nothing about this car but my intuition is to try to avoid consistently operating something at the extreme end of its capabilities.

For all we know there is a software limiter meaning its top speed is well within the safe range. It would be pretty poor to sell a car that would fail quickly under normal usage.

Going that slow on, say, 101 south of San Jose w/no traffic would get you honked at, flipped the bird, or worse.

If the road is wide open, and I'm in the right lane minding the speed limit, anyone that gets mad at my speed clearly deserves it.

Sometimes they end up passing the pain on to the law abiding driver: https://twitter.com/greentheonly/status/1326755485610020864 .

I feel like that example could have hit someone going 90 just as easily.

Even though the max speed is 70, I feel like 75 is the average traffic flow speed.

And yet at 70mph on California highways, most traffic will be zooming past you...

Only a few hours a day. The rest everyone is snarled in bumper to bumper traffic.

It hasn't been that way for the past 8 months.

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