Speed Wobbles

[Chavo]

Years ago, I challenged a skater-hating co-worker to bomb a nearby short hill. It only took 30 feet for him to get severe speed wobbles and get bucked off.

I was interested to see why he got them and I didn't. Another co-worker with an engineering background suggested that it was because of my stable stance (I tend to keep still and lean over the front truck down hills). On the other hand, he skated when he was younger and looked fairly confident going in.

What causes them? What role do trucks play? How do I stop it? I only ask because one of my worst slams ever was from not being able to recover from speed wobbles going 35 mph down a street. I still take it easy down hills because of this fear.

[pinch a loaf]

[pinch a loaf]

I only ask because one of my worst slams ever was from not being able to recover from speed wobbles going 35 mph down a street. I still take it easy down hills because of this fear.

Did Bill Burr ask you if you were alright?

5:40

[Chavo]

Expand Quote

I only ask because one of my worst slams ever was from not being able to recover from speed wobbles going 35 mph down a street. I still take it easy down hills because of this fear.

[close]

Did Bill Burr ask you if you were alright?

5:40

I turned it off after 10 seconds. Would you mind re-capping the story and/or just summarize the punchline of the joke you're trying to make?

[Andrew]

ive heard Frank Gerwer describe it like trying to just plant your feet as solidly as possible , pretending as if you were resisting someone who was trying to lift you off the ground

[ChuckRamone]

haha man, I love videos of longboarders getting speed wobbles and eating shit. does anyone know the source of the one dong juan has as his signature? it's a longboarder skitching on a taxi and he totally fucking eats it.

[Main]

My uncle got remarried at some nice resort a few months ago, and right after the ceremony ended I went out to my car, grabbed my board and proceeded to bomb the gnarliest hill I've ever skated, while in a suit. I was riding wobbly loose Ace's and they did fine, then towards the bottom I did a long manual and once I put the front truck down I immediately started getting speed wobbles. I felt like I was going close to 20mph. Scariest thing that's ever happened to me, but somehow I managed to stay on my board. Best feeling ever when you are on the verge of eating shit but you don't.

[Abyss1]

Expand Quote

Expand Quote

I only ask because one of my worst slams ever was from not being able to recover from speed wobbles going 35 mph down a street. I still take it easy down hills because of this fear.

[close]

Did Bill Burr ask you if you were alright?

5:40

[close]

I turned it off after 10 seconds. Would you mind re-capping the story and/or just summarize the punchline of the joke you're trying to make?

Hilarous story about a kid bombing Griffith Park Hill going fast a fuck and basically Bill sees him get the wobbles  ...His explanation of the fall is great go to 6:00 min

[Iceman]

i wish there was a bill burr filter for skate videos. him describing the slam instead of having to see it.

[Abyss1]

i wish there was a bill burr filter for skate videos. him describing the slam instead of having to see it.

yes

[Ticallion Stallion]

I was dying at log roll. And bouncing up of his elbow...   Worst wobbles i had i tried running of the board rolled and proceeded slide on my back. About 14 years ago.

[mynameisnotjeff]

My friend lives in the Echo Park/Silverlake are in LA which has hills. She was having a BBQ and some of us had our boards. People were bombing the hill she lives on and to my surprise 2 of my friends who didn't skate did it. I was stoked and went for it only to wobble and slide to the bottom. Never again.

[ducky darnsworth]

i skitched on th back of my dads car in a parking lot once and got up to about 30mph, but my trucks loosen up more than i had thought and i started getting speed wobbles, so i got real low still hanging on to the car, and my board just flew out and i slide for a few feet, my neck was hurting after that and my white t shirt looked liked it got ran over, besides that it was pretty uneventful,  theres not really any hills here besides some overpasses so i dont have too much experience with the wobbles

[Phillip Flathead]

Trucks play a somewhat significant role, the shorter the wheelbase is the less stable it should be at high speeds, same with the width of the trucks. I think the durometer of bushings plays a bigger role than how tight they are, because a bushing under abnormal load won't perform predictably.

I do know that towing a trailer at speeds above 65 often causes the same sort of speed wobbles.  As for why they happen, I think it's a combination of a few things:

1. High speed=high wind resistance and not being perfectly symmetrical pitches you one way or another, and the same for updraft, resulting in rapidly changing high intensity back and forth oscillations (wobbles).

2. Imperfect traction combined with a lot of loose objects causing a sort of shock absorber effect at the trucks, causing them to rapidly move.

3. Inability to achieve a point of perfect balance being magnified by lots of vibration from the ground.

After a certain point the wobbles become so intense that either the wheels lose traction or you lose balance relative to the board, resulting in eating it.

Things that help are: staying low, hard bushings, long wheelbase, centered stance, confidence, and powerslides.  As long as you have frontside powerslides down and some hard wheels, you can go down pretty much any hill because you can control your speed.

[Chavo]

Trucks play a somewhat significant role, the shorter the wheelbase is the less stable it should be at high speeds, same with the width of the trucks. I think the durometer of bushings plays a bigger role than how tight they are, because a bushing under abnormal load won't perform predictably.

I do know that towing a trailer at speeds above 65 often causes the same sort of speed wobbles.  As for why they happen, I think it's a combination of a few things:

1. High speed=high wind resistance and not being perfectly symmetrical pitches you one way or another, and the same for updraft, resulting in rapidly changing high intensity back and forth oscillations (wobbles).

2. Imperfect traction combined with a lot of loose objects causing a sort of shock absorber effect at the trucks, causing them to rapidly move.

3. Inability to achieve a point of perfect balance being magnified by lots of vibration from the ground.

After a certain point the wobbles become so intense that either the wheels lose traction or you lose balance relative to the board, resulting in eating it.

Things that help are: staying low, hard bushings, long wheelbase, centered stance, confidence, and powerslides.  As long as you have frontside powerslides down and some hard wheels, you can go down pretty much any hill because you can control your speed.

I do not know much about the science behind speed wobbles, but I recognize some common factors: beginners tend to be more susceptible, leaning back is at high speeds makes it worse, and sudden body movements can cause them.

Some trucks are more prone, but I don't know why. I saw an article by a longboard truck manufacturer about trail and caster, however, he erroneously drew the steering axis along the kingpin when it should be drawn from the pivot cup through the middle of the hanger yoke. Judging by the variety of speed wobble slam youtube videos, I think the longboard world hasn't solved the problem either.

As far as powersliding down hills, it would be nice to bomb straight down without having to scrub off speed. Besides the danger of discarded elotes, I get scared above 25 mph.

I tried once to crouch down and grab the board, but that made things worse, as my body now wobbled with the board until I crashed. Once it starts, I've never been able to stop it.

[Phillip Flathead]

It makes sense that leaning back would cause them, it puts increased pressure on one truck, which makes the trucks turn easier, magnifying the effect.

I found that article you were talking about and I'm pretty sure that the axis is drawn correct. If you take a regular truck and loosen it so you can move it easily, you can see that as you push one side down, it moves toward the kingpin, not the pivot.

This is ultimately irrelevant though, as in either case, a truck with an axle farther out (i.e. Ventures) will have a more positive caster angle and therefore will be more stable.  The byproduct of a more positive caster is a longer wheelbase, which makes it even more stable.

What I take away from this is that for a truck that is stable at high speed, you want ventures with hard bushings on a deck with a long wheelbase.  Lower center of gravity also makes for more stability, so heavy low trucks with no risers and small and heavy wheels would theoretically make for a more stable ride, but to what extent I cannot answer.

[Phillip Flathead]

HOLY CRAP I JUST FIGURED IT OUT

Since the front and back truck are facing in opposite directions, the front has a positive caster and the back has a negative caster. This means that the front is less likely to wobble under speed than the back. This is why leaning back is bad but leaning forward is stabilizing.

The idea setup would be venture front, thunder(?) back truck, and leaning slightly forward. However this isn't too feasible (having two different trucks) so I would just get whatever truck has a moderate or large positive caster and make sure to lean forward and get ultra hard bushings for the rear especially.

[Roisto]

I was talking about this with a friend who doesn't skate, but sometimes borrows her friend's cruiser to go down moderate hills where she lives these days. She asked me why they occur and what she can do to prevent it. I told her to just learn how to skate better as for example for me I clearly get speed wobbles way earlier going switch than I get going regular. You can dampen the vibrations up to a higher and higher point, the more comfortable you are on the board. And I'm not comfortable going down any hills switch and that clearly shows.

As for the reasons why they happen, I think Phillip Flathead pretty much nailed it. Pretty much just vibration caused by many things, which leads to the trucks resonating and if you are not able to counter it, you'll wobble and eat shit.

[BAZOOKA7]

ive heard Frank Gerwer describe it like trying to just plant your feet as solidly as possible , pretending as if you were resisting someone who was trying to lift you off the ground

Just realized that is kinda exactly how it is haha, never realized this

[ungzilla]

Like any vehicle, turning the rear set of wheels results in faster turns, think of a forklift, any hand-cart you push around, that type of shit. So weight over the front trucks and/or much tighter rear trucks as compared to the front, those make intuitive sense to me as things that would reduce the incidence of wobbles.

I've always thought wobbles were basically your body not being able to respond quickly or sensitively enough to what your board is doing (or your board reacting more quickly to your input than you can compensate for), similar to harmonic resonance. You try shift your weight to correct one way, but at high speeds, the board reacts very quickly, and you try to compensate back the other way, over do it, and a positive feedback loop results, with the frequency getting greater and greater until you get pitched. I would think that anything that would slow down the speed at which the board reacts to your movements would counteract speed wobbles: increased wheelbase, trucks with increased turning radius, that sort of thing.

Damn I hate even thinking about the wobbles. I like bombing hills but mostly because powerslides feel cool, not for the sensation of speed.

[AitchBeeGayBuh]

My cruiser board is an 8.5 with trucks jingle jangling (like matt rodriguez or daewon), and 61mm wheels... On paper this sounds terrible to take down hills.

My first time takin it down this good sized hill I take everyday to pick up my son I was kinda scared and carved a bit n did a couple powerslides in the beginning.

Now I push up to that bish with a nice tail wind n just take it straight down... I've yet to get wobbles.

I've gone down other hills too n found out with loose trucks it's real easy to carve back n forth where u can kinda get into a 'flow'... The only thing that scares me is not havin enough flat to ride out of it and/or goin into intersections or blind turns.

What someone else said too: riding that loose ass board made me adapt to havin most of my weight in my front, that might be something.

Does anyone have any experience or can explain this?

[Phillip Flathead]

So basically the caster of trucks affects stability, and the front has the same amount of positive caster as the back does negative. Therefore, leaning forward should yield more stability.

Carving back and forth helps too, it effectively reduced the slope of the hill by increasing distance travelled per foot of descent.

Did some more research, one of the chief principles of speed wobbles is that a slight movement turning either way results in wind resistance causing you to turn back until the same thing happens on the opposite side. This oscillation increases in intensity and frequency until you get bucked.

As far as intersections go, obviously a spotter at the bottom helps you with traffic and they can also hit a crosswalk button so you can go through the intersection with traffic. If I approach an intersection with cross traffic I do some slides to slow down, and go all the way over to the edge of the road (if no traffic) so I can swing wide the other way and make a quick left turn and make it into the bike lane going the wrong way. Worst case scenario is to bust a big frontside slide and bend down and lean back to slide the rest of it out on your ass. Better to get some road rash on your backside than get hit or lost some face skin and get a nasty concussion

[The Lap Dancer]

The question of this topic was not how to get rid of speed wobbles but how to survive them when you get them. Like that dude at 1:35

[Phillip Flathead]

The question of this topic was not how to get rid of speed wobbles but how to survive them when you get them. Like that dude at 1:35

Looks like he just held on and they stopped when he stopped accelerating (the hill sort of leveled off)

[Chavo]

It makes sense that leaning back would cause them, it puts increased pressure on one truck, which makes the trucks turn easier, magnifying the effect.

I found that article you were talking about and I'm pretty sure that the axis is drawn correct. If you take a regular truck and loosen it so you can move it easily, you can see that as you push one side down, it moves toward the kingpin, not the pivot.

This is ultimately irrelevant though, as in either case, a truck with an axle farther out (i.e. Ventures) will have a more positive caster angle and therefore will be more stable.  The byproduct of a more positive caster is a longer wheelbase, which makes it even more stable.

What I take away from this is that for a truck that is stable at high speed, you want ventures with hard bushings on a deck with a long wheelbase.  Lower center of gravity also makes for more stability, so heavy low trucks with no risers and small and heavy wheels would theoretically make for a more stable ride, but to what extent I cannot answer.

Steering axis is different from turning axis, otherwise the steering axis on a bicycle would be drawn perpendicular to its head tube. I do not know if one can even compare the mechanics of skateboard trucks to a shopping cart or bicycle. The hanger turns all over the place on the pivot axis, unlike a bicycle. With an Indy, if you push a wheel down, it starts going straight down before it moves increasingly towards the middle of the board (old Trackers allowed very restricted turning with its pivot, which led to breakage since pivoting freely is what a truck wants to naturally do).

[David Wozniak]

The question of this topic was not how to get rid of speed wobbles but how to survive them when you get them. Like that dude at 1:35

Why not you guys wear a helmet when boarding?

[StinkyLarry]

Wide stance, keep low and pray. It's the kinda thing where if you try to fix it you'll make it worse, I try to focus more on keeping it steady from the waist up and let your legs be one with the wobble. Sometimes though you just gotta eat it.

[Willie]

I don't do a lot of downhill unless I find a closed street or one with good visibility because I'm super paranoid about cars and cracks but I'd say the one thing I do is treat it like a snowboard and consciously favor one side or another. Even if going straight I've probably got more weight on my heel (one reason being that I'd rather fall towards my ass side).

I think being too neutral is one way the wobbles start. Something sets off a swerve in a direction you aren't prepared to turn and then you make a series of overcompensations trying to get back to straight.

[Chavo]

I don't do a lot of downhill unless I find a closed street or one with good visibility because I'm super paranoid about cars and cracks but I'd say the one thing I do is treat it like a snowboard and consciously favor one side or another. Even if going straight I've probably got more weight on my heel (one reason being that I'd rather fall towards my ass side).

I think being too neutral is one way the wobbles start. Something sets off a swerve in a direction you aren't prepared to turn and then you make a series of overcompensations trying to get back to straight.

Skateboard wheels are so small (compared to other wheeled transports) that any natural unevenness on the surface can set it off. Whey I get them, it just happens suddenly and quickly. There is no countering on my part since the oscillations are so fast.

[AllBranFlakes69]

HOLY CRAP I JUST FIGURED IT OUT

Since the front and back truck are facing in opposite directions, the front has a positive caster and the back has a negative caster. This means that the front is less likely to wobble under speed than the back. This is why leaning back is bad but leaning forward is stabilizing.

The idea setup would be venture front, thunder(?) back truck, and leaning slightly forward. However this isn't too feasible (having two different trucks) so I would just get whatever truck has a moderate or large positive caster and make sure to lean forward and get ultra hard bushings for the rear especially.

So if I put my back truck on backwards.... Problem solved!!