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Rivian's TM-B electric bike

(www.theverge.com)
190 points hasheddan | 6 comments | | HN request time: 0s | source | bottom
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dreamcompiler ◴[] No.45673731[source]
808Wh battery and 100 miles of range. These two numbers track with each other and are roughly believable.

OTOH, with a battery this big, a generator powered by the pedals, and regen braking this thing has to be heavy. I'd expect it to weigh at least 80 lbs. More likely 100. The fact that their "specs" say nothing about weight suggests they're embarrassed about the weight.

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jeffbee ◴[] No.45675314[source]
Regen braking is how you can tell this was designed by a moron. The energy balance simply does not favor regenerative braking on a bicycle, especially a bicycle that flippantly ignores aerodynamics like this one does. A bicyclist loses roughly all of their energy to air resistance. It's not a truck. There is not substantial potential energy to be recaptured going down hills.
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Spunkie ◴[] No.45675805[source]
I find regen exciting for it's ability to slow down my brake pads getting shredded every month. The fact that I get some energy back from it is mostly a bonus.
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1. nradov ◴[] No.45676411{3}[source]
How are you shredding brake pads every month?
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2. Spunkie ◴[] No.45677206[source]
My town is on the side of a volcano, a 30% grade is like the average hill here.

That combines with the heavy weight of an ebike, another 50lb+ of cargo in the saddlebags, plus my exceptionally fat ass means I burn through a pair of front brake pads about once a month if I'm running errands most days.

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3. azundo ◴[] No.45677223[source]
It wasn't quite monthly but on my radwagon 4 I would change the pads every other month at least. Hauling two kids around SF on a heavy bike plus a little bit of poor design on Rad's part.
4. skeeter2020 ◴[] No.45678127[source]
>> a 30% grade is like the average hill here.

So the steepest roads in the world have small sections where the grade exceeds 30%; none maintain it or "average" 30%.

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5. nradov ◴[] No.45678413{3}[source]
Seriously. Even the Mauna Kea volcano climb doesn't have 30% grades.

https://www.strava.com/segments/1504789

6. Spunkie ◴[] No.45678709{3}[source]
Ya sorry I always get it mixed up with the % grade thing.

When I'm in my car the dash reads on the hills here between 12° all the way up to 16° on the switchback into the valley. The new market is up a 14° hill.

So closer to ~24% grade average maybe? It's damn steep is the point regardless.