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Can I Stop Speed Wobbles

author
James Smith
• Thursday, 03 December, 2020
• 8 min read

CJ: For starters, speed jobs can be caused by a number of different reasons. Loose trucks can give you too much turning ability, making your set up hyper-responsive for any speed over 10-20mph.

stop start they wobbles speed them shimmy
(Source: cyclingtips.com)

Contents

Its very natural for the human body to lean back when going an uncomfortable speed. Place your front foot as far forward as possible without hanging your toes or heel over the railing.

Sam: Before we get in to the nitty-gritty details on how to eliminate the horrible fishtailing known as speed wobbles, you must first understand the primary cause of speed wobble. Speed wobble occurs when the rear of the board begins turning before the front of the board, the front truck will stay relatively straight while the back truck will turn back and forth violently resulting in a hefty amount of road rash.

One of the most common mistakes that beginners encounter when learning how to ride is putting all the weight on the back truck of the board. When riding make sure to keep your knees bent and most of your weight on your front foot.

Sudden movements make speed wobbles worse, so when you shift your weight, do so with caution and confidence. Lower angles will cause the truck to turn even less which will make for a more stable ride.

A lot of us here at Motion Board shop ride with 184 mm Caliber Trucks with 44 degree baseplates. It’s easier said than done when you’re bombing a hill and start to wobble, but relaxing your body will go a long way.

stop moving freakin jules raoul everybody remix amazon cant
(Source: www.amazon.com)

Bending your knees will lower your center of gravity and give you much more stability, but it won’t always get rid of speed wobbles. Get low, relax your legs and focus on keeping your upper body over your board and positioned slightly forward.

Attack the hill and if your board starts to wobble, stay relaxed and confident. It’s much easier to feel relaxed while bombing a hill if you know you could throw a speed check or slide to a stop at any time.

Learning various stopping techniques and being comfortable doing them is one of the most important skills any long boarder can have. Terrified of crashing, you pull over to the side of the road, making the quick judgement that if you’re going to fall off, you’d rather do so on the grassy verge than the unforgiving bitumen.

You unclip a foot and, to your great relief, the bike gradually comes back under your control. Speed wobble, or shimmy, can be defined as “an oscillation of the bicycle steering assembly at frequencies too high for an effective reaction of the rider.” It’s a phenomenon that’s also seen in motorbikes, skateboards, shopping trolleys, and airplane landing gear.

In bikes, speed wobble starts when something causes the front wheel to accelerate to one side. Damon Richard is the Engineering Manager for Road Bikes at Cannon dale and a man with a wealth of experience when it comes to frame design.

spinrite crester dealers welcome arrow
(Source: spinritecrester.com)

“Today, most frames are stiff enough that shimmy is less common, and with fewer riders experiencing it, the need to know has also decreased, and in some areas the knowledge might be almost lost in the mists of time,” Richard opines. But some studies have included real-world measurements, such as the latest paper in this space from Italian researchers at the Polytechnic di Milano (Polytechnic University of Milan).

Led by Nicole Tomato, the researchers rigged up a 52 cm road bike with six inertial measurement units containing accelerometers and gyroscopes (Imus 1-6 in the image below). All the units were connected to a Raspberry Pi single-board computer on the down tube and a power bank installed on the seat post.

One day in 2017 (the wheels of academic research turn slowly) a test subject rode the instrumented bike down a hill near Echo, Lombardy to see if they could detect shimmy. While it’s possible to initiate a speed wobble by bashing on the handlebars mid-descent (as in the terrifying video below from Damon Richard) the test subject in this case didn’t apply any deliberate stimulus to promote the onset of shimmy.

Data from this latest study shows something less obvious too: oscillations at the seat stays are out of phase with those on the top tube. The fork, meanwhile, twists slightly upwards in the direction the wheel is facing during shimmy.

The handlebar twists downwards in the same direction, creating torsion in the front steering assembly. If the shimmy happened when you had your hands off the bars, gently put them back on again (see the Richard video above).

skateboard stop speed carving shed
(Source: stixrideshop.com)

Anecdotally, the easiest way to bring shimmy under control is to clamp your knees to the top tube. “This works by adding damping (your body contacting the frame) and increasing the stiffness of the system,” Richard explains.

“Resist as far as possible the temptation to jump off the bicycle, which may appear to be the lesser evil in that situation,” they write. “Try not to fall, and not to hit other vehicles, or go off-road, for the time necessary to decrease the speed below the threshold of the disappearance of shimmy [ed.

“Unfortunately, this is a rather difficult task if the road remains very and curvy because brakes cannot be used effectively when cornering, and they may, at first, even cause an increase in the amplitude of the steering oscillation.” Again, the key seems to be to remain as calm as possible, to alter something about the system to destabilize the oscillations, and to reduce your speed safely.

Well, just like when you’re in the middle of a speed wobble, you need to change something about the system to discourage the scary equilibrium of shimmy from happening again. “To stop a bike from shimmying again, change the mass or stiffness of the system,” Richard says.

“Less mass and more stiffness both increase the resonant frequency of the system, making shimmy less likely.” “The frame and fork are the biggest springs in the system, so changing to a stiffer frame set is a good option, though expensive,” Richard says.

(Source: www.youtube.com)

More-supple tires seem to be a good (and relatively inexpensive) place to start, in order to provide greater damping at the road: “Softer or less structured tires, may altogether prevent the onset of shimmy,” write Tomato and co in a 2017 paper. If changing components doesn’t work, it might be worth checking that your wheels are round and true.

It could be that slight imperfections in the front wheel are giving your bike the encouragement it needs to generate lateral movement once at speed. “If you ask around you will no doubt hear about various mechanical fixes: adjust bearings, check alignment, tighten spokes, etc,” Richard says.

Again, finding something that works to stop the shimmy will likely be a process of trial and error, often with an associated cost. Your brain tries to keep you going straight when you hit small imperfections in the road and over corrects.

Before you know it, you are wobbling all over and eventually lose control and eat it real good. However, it is ultimately up to you to skate within your limits and ALWAYS wear a certified helmet and other protective gear.

Practicing GOOD habits with the right long board gear can get you CLOSER to perfect. However, there are always places for you to improve your long boarding skills and there is always a chance for you to fall on your face, I don't care how well you practice and how good you get.

(Source: www.youtube.com)

The only way to truly overcome the dreaded wobbles in most situations is to build your skills by becoming more and more comfortable with speed. In this case, the source of the problem is the over correcting action that the rider takes when hitting the imperfections in the road.

The only way to truly overcome the dreaded wobbles in most situations is to build your skills by becoming more and more comfortable with speed. Most riders start by utilizing set-ups that make it hard to get wobbles.

Top mounts might be used by the pros, but they are usually not a good starting point for a first speed board. Top mount long boards generally make it easier to get speed wobbles because they position the rider above the trucks.

Note that this is not to say if you get a board like the Landyachtz Eve you'll instantly be able to bomb like a mad man. No one surfed triple overhead before first mastering the whitewash.

Let's dive into each one of those options, why they seem to work, and why they ultimately can lead you into a false sense of security, wobble hard, and make you face plant harder than your mom can garden. If your current long board set up wobbles bad, your first and cheapest option is to tighten your trucks.

(Source: www.youtube.com)

Tightening your trucks is simply postponing the point at which you wobble. When you go faster and get the wobbles again, they are going to hit you quicker (less warning) and harder than before.

In addition, I can 't tell you how many times I've seen skaters absolutely destroy bushings by over tightening their trucks. Lower degree baseplates give the rider more lean and less turn.

The last option you have in terms of changing set up to help reduce speed wobbles is to increase the wheelbase of your long board complete. Think about a go-kart (Landyachtz Dinghy) and a full size car (Loaded Bhangra).

The go-kart is quicker in sharp corners, but more squirrelly when you get going fast in a straight line. Once again I am going to reiterate: a longer wheelbase is simply postponing the point at which you wobble.

The way in which you ride the long board, regardless of the set up, is going to impact your success or failure at avoiding speed wobbles. Because turning and controlling a long board is largely based on the front truck, it's important to keep your weight there.

motion stop thing
(Source: www.youtube.com)

Another common method for overcoming wobbles on your long board is to carve them out. By consciously forcing a carve back and forth, the over correcting action of your brain can be overcome.

Seriously consider buying 2-3 boards over time, with each set up getting more and more into turning and less into complete stability.

Other Articles You Might Be Interested In

01: Jean Zorbibe
02: Jeep Wobbles
03: Jeep Wobbles At 40 Mph
04: Jeep Wobbles At 55 Mph
05: Jeep Wobbles At High Speeds
06: Jeep Wobbles When Braking
07: Jeep Wobbles When Hitting Bump
08: Jeep Wobbles When Turning
09: Jeff X Rainbow Dash
10: Jelly Wobbles
Sources
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2 www.facebook.com - https://www.facebook.com/Jelly-Wobbles-166004373421514/
3 www.howitworksdaily.com - https://www.howitworksdaily.com/why-does-jelly-wobble/
4 www.theguardian.com - https://www.theguardian.com/lifeandstyle/2013/jul/06/ask-grown-up-why-jelly-wobbles
5 www.theguardian.com - https://www.theguardian.com/notesandqueries/query/0,,-1171,00.html
6 physics.aps.org - https://physics.aps.org/articles/v11/41
7 www.rsc.org - https://www.rsc.org/news-events/articles/2006/07-july/jelly-wobble/
8 simplyinish.ie - https://simplyinish.ie/tag/jelly-wobbles/
9 kidscraftroom.com - https://kidscraftroom.com/jelly-tummy-wibble-wobble/
10 www.discogs.com - https://www.discogs.com/Noise-Engineer-Jelly-Wobble/release/2290531
11 www.yourdictionary.com - https://www.yourdictionary.com/wobble