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Comment by IanDrake | Hacker News Reader

This sounds cool, but (IMO) it's actually a bad idea. When I was in my late teens / early twenties, I essentially had a 180HP version of this.

It was a lot more expensive back then: $4,000 for the 1984 Chevy Blazer and $0 dollars for an extension cord we found in the garage, but going going fast on a skateboard, no matter what the method, is dangerous.

The worst part of this idea is "braking". I can assure you the only good way to brake a skate board at speed is a power slide, which you need to be an expert to do.

I've hit sand at speed and, even knowing it was coming, the slight braking power of the sand was enough to throw me. It's difficult to explain, but between knowing how far to lean against the braking force AND managing your balance side to side on the trucks, it ends up being harder to pull off than a good ole power slide.

That said, a roller blade version of this would be cool.

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Are you suggesting that, because it takes skill to operate, it's a bad idea?

I commute on my longboard every day between the parking structure on campus and my building, which is about a mile away - takes me 10 minutes of kicking the board around and working up a sweat.

An electric longboard woud fit right into my current commute, except I'd arrive at work without my shirt soaked through.

For this type of commuting, a couple of days practice in a empty parking garage or lot gets you good enough to safely commute, and if the SF hills are intimidating, you can always walk down them.

As for braking, they indicate that the remote does have a brake slider, and by using regenerative braking, they can slow the board down (to some extent). You would still need to know how to brake the board, but the board can stop itself.

This would also be a super fun toy - I already take my longboard out to race down hills, with this I get to ride up before I fly down.

But, a rollerblade version? Can you explain how that doesn't have the same concerns you raised? Rollerblades are even more difficult to brake than skateboards, and you're committed on rollerblades, while on a skateboard you can jump off and carry the board whenever it's inappropriate or too difficult to ride it. There's also zero cost to hopping on a skateboard, while rollerblades involves sitting down and changing your shoes.

I doubt this product will fix all of the transportation woes of the US (which their marketing seems to point to), but it's great for current longboarders and people already interested in unconventional transportation options.

>Are you suggesting that, because it takes skill to operate, it's a bad idea?

Jeeze, I guess I did, I must be getting old. It is a cool idea.

>But, a rollerblade version? Can you explain...

Setup aside, going fast on roller blades is much more controlled than on a skateboard. You can't bail, sure, but you also won't get the death wobbles.

At speed, you can inline your feet (one foot in front of the other) and put 80% of your weight on your back foot, since the only instability is front to back. This guards you against pebbles, cracks, and what not. You have the same side to side stability as a someone riding a bike.

Skateboards at speed have instability front to back (obviously your weight is back to guard against pebbles, etc..) but also side to side. Keeping the death wobbles away takes a lot of practice.

Behind the Blazer I got up to 45Mph on my blades, but not even close to that on a skate board (with tight trucks and soft wheels). At the time I considered myself to be about equal in terms of skill with both.

(edit for line break)

It was a surprise to me when I learned it on a motorbike safety course, but it's useful to know that an impact with a solid object at 35mph is only 50% survivable - a blow to the torso at that speed will tear the aorta. It's even worse if the object is something small in profile like a lamp or sign post.

Here's a forum post by a guy who was lucky to survive a crash at 30mph (some nasty post-op pictures - may be NSFW): http://www.bikechatforums.com/viewtopic.php?t=253168

The motor braking is powered, not regenerative, so it can brake so hard as to throw you forward off the board! (Rode one of their early prototypes. Sheer awesomeness!!)

Your posting just made me realize how smart the segway concept is. The brake force automatically matches how much you lean back.

Disclosure: I have never "ridden" a skateboard.

Wouldn't it be very different braking by yourself than being slowed down by anything on the road? You control exactly the speed and brake force you apply to the board so you can balance/react. I see the guys in the video doing pretty well.

Physics of a table attached to a car using a rope are very different from this.

I agree that yes, you should definitely be experienced if you're going to be going 20mph on a longboard. It's fast. But, if you've got brakes, and I've ridden both electric skateboards with brakes and non-electric skateboards with brakes before and both are easy to use, you'll probably never end up going that fast in the first place unless you're being reckless.

A power slide is one way to stop, but brakes work just fine. The reason the sand throws people isn't because they're slowing down, it's that they don't expect it and can't predict how quickly it will slow them down. Decent brakes have neither of those problems.

Maybe I'm thinking about it wrong. Slowing down vs. braking, I mean.

If I'm going 20mph, "braking" to me means coming to a stop in an equivalent distance as a car or bike going the same speed.

Are the brakes that you've used stable at that rate of deceleration?

It's not so much the brakes being stable, it's the operator's body with its c.g. 1m above the board. A maximum deceleration for tires on a good road is generally 0.6-0.8G. So in order to avoid being (literally) thrown off the board the rider needs to be leaning backwards by 30-40 degrees before applying the brakes.

There's no equivalent to this behavior in any other vehicle. In a car you just hit the pedal, on a bike you just squeeze the handles and hold on, on a seque (the closest equivalent I can think of) you must lean back to actuate the stopping.

On a long board at 20mph if you "hit the brakes" you crash, period. That just doesn't sound equivalently safe to me.

In a bike just sqeueezing the handle will also throw you away, especially when downhill. It takes practice as well to be able to move your gravity center backward in emergency brakings.

It is more about using the handlebars to resist your body's forward momentum.

If you slam on the brakes, yes, you'll fall. However in my experience in practice it is not hard to get used to braking on a longboard. I've done it and seen lots of other people do it without crashing.

You probably don't stop as fast as you would on a car or a bike, but you learn to control the speed you stop at pretty quickly.

I don't think longboarding will ever be as safe as riding a bike, but braking isn't the biggest reason for that.

Makes me wonder if a two wheeled longboard -- a Segway with no handlebar you ride like a longboard -- might not give us the best of both worlds.

> There's no equivalent to this behavior in any other vehicle.

http://www.youtube.com/watch?v=puLeE7sESeI

I've had the somewhat peculiar experience of braking on a bike when the handlebars weren't completely attached to the frame.

Being able to apply a stopping force without simultaneously being able to fully brace your upper body against a solidly connected part of the bike was a very different, and to my mind, rather unsafe, condition.

I'd think liability issues would pretty grossly limit the merchantability of the powered skateboard. Electric scooters offer the benefit of a handlebar as well.

At 10mph (a more likely speed for this 2.5hp board), worst case, I jump off and run-stop (or roll)... twisted ankle/etc is possible. But at $1200 a piece, I'd really regret the loss/damage that might cause the to the board.

> twisted ankle/etc is possible. But at $1200 a piece, I'd really regret the loss/damage that might cause the to the board.

I value my ankles and epidermis at several dozen times "$1200 a piece". I consider your stance to be the utter epitome of foolishness.

It would seem that 180HP is indeed a bad idea. These boards are aiming for 2.5 horses, which sounds like a blast.

Yes, it was a very bad idea.

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