yes, this is the exact one I’ve used. works really well on the rear truck, horrible on the front truck.
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Can’t believe nobody pinged me for this one, this is one of the things that I’m most familiar with.
What are speed wobbles?
Speed wobble is when the mass of the board moves left and right faster than the mass of the rider steering it.
You’ve got this big heavy thing on top, and this smaller mass below.
Say the rider is static left to right and the board is a bit off center.
At the right speed, the riders weight causes the board to lean, which brings the board back under your feet and it all stabalizes. That how its supposed to work, and that’s why you have people able to go so fast on skateboards.
Speed wobble happens because the weight of the rider is heavier with more inertia and it doesn’t change direction as fast as this much smaller weight thats able to push off the road with its grippy wheels.
So its not really so much about oscillations front to rear like you’ll often see
But osculations top to bottom between the riders mass, and the boards mass.
Say you’re riding and you’re going fast and you put a little lean in there and it zips your board off to the right.
That’s going to result in a little bit of energy moving your big body to the right as well.
But your weight is still doing its thing to help steer the board.
So even though you zipped the board to one side, its going to prefer to come right back under you.
Only thing is, you’re still moving to the right from the time the board shot that way.
Before you know it, your body’s gone right past the center of the board, and now you’re in the same position you were in before, but mirrored.
The way to not get speed wobble is not not let the board move left/right faster than the weight of the rider above it. The faster you go, that faster that board can move left to right. When you get up to like 40mph, there’s so much energy in that system that board could dart right out from under your feet before you know it if you’re not staying on top of it.
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Shartis? is that you? 
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How does equipment setup make this better/worse and what are the tradeoffs:
-truck width
Truck width is minimal.
You do get a tiny bit of additional stability, but far more it just affects the feel of the the setup.
How this works is making the wheels have to speed up or slow down slightly while turning.
So if you have a longer axle, for the same turning angle the wheel has to move a further distance to get there. And as the wheel is rolling on the ground, that means it needs to either speed up or slow down.
Its the weight of the wheels having to speed up or slow down that matters, so hanger width and wheel weight have the same effect on feel in this regard. Its typically easier to change hanger widths than wheel weight however.
-kingpin angle
The term to think about here isn’t the kingpin angle, but the pivot angle. On RKPs that roughly correlates with the kingpin angle, but not exactly.
The pivot angle is the angle from the center of the pivot, to the center of the bushing seat.
That is how you measure it, and it works on both TKPs, RKPs, and other kingpin varieties.
The pivot angle changes how many degrees of turning you get for each degree of deck lean.
for 45* pivot angle, you get 1 degree of steering for every degree of lean.
Higher than that, say 60* pivot angle, you’ll get quite a bit more than 1 degree of steering for each degree of lean.
The other thing that changes is leverage advantage.
On one side of the baseplate you have the deck which is having force put into it by you the rider.
On the opposite side of it you have the hanger, which is having force put into it by the road.
The lower the pivot angle, the more control authority the rider will have over the influences of the road.
Go too extreme, much past 60 degrees, and you’ll find that the bumps and movement of the road will actually be pushing you around and it will be the thing controlling the lean of the deck more than you.
Like turning angle, this leverage system is split even at 45 degrees, that still typically leaves the rider with plenty of advantage. But for setups with speed I typically don’t recommend going higher than 45.
Usually pivot angle is measured relative to the deck, and most of the time that’s fine.
But strictly speaking you should actually be measuring against the angle of the line between the axles, or the road. Say you put a riser only on your front truck, that’s going to cause your whole board to pitch back and might add an extra 2 degrees of turning on the font, and take away 2 degrees from the rear.
Most setups don’t have anything like that, so just measuring off the deck is fine.
-angled risers (and is this the same effect as angled kingpin?)
Yes, the purpose of angled risers is the change the pivot angle.
Wedges/dewedges build into the decks also do the same thing.
-Wheel base
Wheel base works together with the pivot angle to create your turning radius.
Turning radius is ultimately kinda the thing that matters, but two setups with the same turning radius aren’t necessarily exactly the same if they’ve got really different wheel bases.
You can mess around and explore the whole wheelbase/pivot angle/turning radius thing using this online calulator.
-bushings
Bushings just restrict movement of the hanger.
They don’t slow the board down or keep it from moving side to side any faster. But what they do is alter how much force is needed. Without bushings, a board would react purely based on your positions and balance over the deck, and you’re essentially having to balance on a tight rope to go in a straight line.
They act as sort of a buffer. They don’t mechanically make the system any more stable, but they do help the rider out in controlling it.
-Center of gravity
On this one, what you want to think about isn’t center of gravity, its the roll axis.
I’ll bring back this graphic, and a new one.
Roll center is the point on the pivot axis directly below the axle.
And the roll axis is the line connecting the roll center between the front and rear truck.
The roll axis is the tightrope on which you are balancing.
What’s actually important about the roll axis is its distance in height from the foot platform.
If you’re running a ton of risers, its like you’re trying to balance on a tight rope while wearing platform shoes. And if you’re running a double drop setup that puts your foot platform below the pivot axis, thats going to make it a lot easier to balance.
However balance isn’t the only thing at play here. The distance between the foot platform and roll axis is also a lever arm which helps give the rider a leverage advantage, and control authority over the setup. Because of these leverage advantages it also has the effect of making bushings feel and act softer the taller you go.
Last thing this contributes is the effect of G forces.
When going slow, a drop deck may feel a lot more stable.
But when you’re going fast and you’re holding tight turns, G-s start to play a big part.
And hopefully you can see with a topmount setup the Gs are actually going to be pushing you back towards center. Too much topmount, and you won’t be able to hold the turn.
And with a double drop the foot platform is actually doing what we call hammocking. It wants to swing out and stay in that turn. Having too much drop can really be a death ride locking you into a turn that you can’t get out of.
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I meant that in a “This is my best subject” sort of way, not “I’m the best at this subject”.
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To be serious though.
Speed wobbles are all about rider skill. Yes the inertia caused by rear drive can cause some butt clenching moments but in reality the better you are at riding a skateboard the better you are at handling the wobbles.
Actually I will broaden that statement and say that the better you are at riding boards then the better you are at riding out wobbles. Board sport is just that. Board sport. The more experience you have with all kinds will do you justice in this endeavour.
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The rider was going to be my part C, but I’m pooped.
I’ve been writing well over an hour.
80% of it can just be summed up as, Keep your weight over your front truck.
Most people learn that through experience, but if somebody can just tell you up front that sure can save some skin.
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Is it easy to throw your weight forward when experiencing the death wobble?
No it is not but then again most saviours are disguised as torment.
Got a bit biblical.
Apologies
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I can’t wait for part C. I spent my youth riding halfpipes. I was pretty good, could do big airs, but my trucks were always a lot tighter than most to prevent speed wobbles on the flat bottom. I could never understand how other people could ride their trucks so loose.
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Just pictures I found. I’m guessing someone had it CNC’d at a shop
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Or you can ride FWD, where all the weight is naturally up front = no wobbles, speaking by experience.
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That will indeed alleviate the acceleration wobbles inherent with powerful drives but it will not help when up to speed.
Only you can do that.
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do I have to have strong ankles?
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I have absolutely no idea.
Ask Syd
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Anybody have good advice for how to take wobble induced by veering one side of the board from asphalt into off-road grass? This is currently the biggest thing trolling me on the nature bike trail, which is just about the only decent place in my town to ride. Sometimes I carve too hard and one side barely goes into the foliage, but it always takes me down pretty quickly…
I feel like front wheel drive would definitely help, along with a rear damper… but anything aside from that (aside from stop being a dumb fuck and stay on the asphalt)
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this is likely a traction issue and occurs to vehicles at speed when the traction on one of the drive wheels unexpectedly changes. is it safe to presume you have “traction control” enabled on your ESC?