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A bike rack should keep your bikes stable and still during transit. That’s one feature that gives you peace of mind while driving.
What you don’t want to see is the bikes swinging around and crashing into each other when you’re on the move.
This article tells you how to keep bikes from swaying on a bike rack.
Which bike rack features should you look for to achieve this bike stability, and what can you do to help?
Why Bikes Wobble On Car Racks
There are a few reasons why bikes wobble on various types of car racks.
On hitch-mounted bike racks, the fight against swaying bikes has to begin at the rack’s connection point. If the hitch connection has play in it, the whole rack moves and causes bikes to move as well.
To keep bikes stable on a rack, the bike rack has to be solidly connected as a starting point. A wobbly hitch is likely to create movement throughout the whole load.
Video: Bike Swaying On A Hitch Rack
Lack Of Lateral Support
A feature that is lacking in some bike racks is lateral support or lateral stability, which may cause bikes to move.
On a trunk rack, a lack of lateral stability may cause the bike to move more than you’d like.
Roof racks tend to be good at holding bikes still, though there’s little to stop lateral bike movement in theory. And you can’t usually see it! These racks tend to have oversized hooks and clamps to help prevent any wobble.
Hitch racks don’t have lateral support or any means of providing it. You’re depending on that rock-solid central connection as the basis for stability.
Related to lateral support is the terrain you’re driving over. Cars don’t tend to move from side to side on smooth asphalt, but things soon change if you go off-road.
Off-road driving places greater demands on a bike rack and is more likely to expose its weaknesses. This is when the car you drive and the rack you use make a difference.
On hanging-style bike racks, which include most trunk racks and some hitch racks, bikes always have the potential to swing from the cradles.
The design of the cradles and their straps may help to prevent this, which we’ll get into a bit later. But hanging bikes and swinging bikes are closely related. It’s a bike-carrying method inherently likely to cause some movement.
Some bike racks come with a “safety strap” as a final step in securing your bikes to the rack. This is more likely on platform-style hitch racks, where the top of the bike is less supported than the base.
A bike rack that comes with too few or ineffective straps is likely to cause wobble. Soft ratcheting straps are usually used to secure wheels or the bike frame.
You should always follow manufacturer’s instructions to the letter when setting up a bike rack. Pay attention to all fixings, hinges, and contact points so that nothing is loose.
With trunk racks, large pads provide stable contact points with the car, which also helps prevent damage.
Don’t proceed with installation if a trunk rack is a poor fit for your car model and its shape or features.
Be wary of fitting a 2” hitch rack onto a 1.25” hitch receiver using an adaptor. Heavy-duty bike racks are not always suitable for the smaller hitch or lower hitch class.
Read more: How to install a bike rack on an SUV
If you load bikes that are heavier than the load limit of your bike rack, you’re likely to create a hazardous amount of wobble and instability.
Heavier bikes usually go on the inner arms or platforms of bike racks (those nearest to the car). The outer bike spaces may even have lower weight limits.
Weather & Drag
Something you cannot control but which has a definite effect on bike stability is the weather. A windy day is more likely to cause bike movement than a still one.
If you’re using a bike rack correctly, chances are the bike(s) will stay stable in the wind or at sensible speeds. But the punishment for an oversight could be severe.
It’s not necessarily the roof rack that will suffer most in these conditions. A sudden strong gust catching a rear-mounted bike may cause movement, especially as it sits perpendicular to the car.
Wear & Tear
Wear and tear of your bike rack, especially its connection points, fixings, and fasteners, may cause some wobble to develop in a bike rack.
Ways To Stop Your Bicycles From Swaying On Car Racks
We’ve looked at the various causes of swaying bikes on a bike rack, so what can you do to prevent it?
Many hitch-mounted bike racks come with an anti-wobble hitch mechanism. This takes various forms, like a wedge or shim, or a hitch tightener that prevents vibration and movement.
If you notice this problem in a new bike rack, there are after-market products you can buy to quickly stop it.
Video: Installing A Hitch Tightener To Stop Bike Rack Wobble
Consider Lateral Support
Some trunk-mounted bike racks include side straps that add lateral support. They’ll often have three or four vertical straps as well, so there’s a strong, stable base on which to hang your bikes.
Roof racks don’t have a great amount of lateral support. They are generally held in place with downward force. Products have materialized in the past to keep bikes still when driving off-road, for instance.
Torque-limiting knobs on roof racks help you to tie down your bikes with more confidence. You needn’t risk over-tightening or under-tightening them.
You’ll often see anti-sway cradles listed among the specs of a hanging-style bike rack (hitch or trunk). These are good to have and may have a proprietary or patented design in some cases.
Anti-sway cradles usually sit at right angles to horizontal cradles and are designed to grip your bike vertically by its seat tube. This restricts movement in the bikes and helps to avoid them knocking into each other during transit.
Add Extra Straps
If intuition tells you the bike load is too wobbly, you can always tie it down further with your own straps. Ratchet straps, bungee cords, or even plain lengths of rope may add valuable stability.
Tying wheels to the bike frame is one way cyclists prevent the movement of wheels during transit. You can also tie various parts of the bike to the bike rack, especially if it’s a tightly secured hitch rack.
Be sure to add the aforementioned safety strap to a bike load if such a strap is provided. Use of this is often a condition of the bike rack guarantee. If the whole load is secured in this way, the chances of bikes moving and falling off are reduced.
Watch Weight Capacities
Be sure to avoid overloading your bike rack. The weight capacity can vary between 30 lbs to 80 lbs per bike, depending on the rack type. Hanging-style racks tend to have the lowest capacities, while platform-style hitch racks have the highest.
You should also pay attention to the tongue weight capacity of your vehicle when installing hitch racks, especially if you intend to carry heavy bikes. However, this is more about your vehicle’s stability than bike movement alone.
Many cyclists leave hitch racks and roof racks on their cars for long durations, as they are compact when unloaded. So, it’s easy to overlook any wear and tear that gradually occurs.
Every once in a while, it’s a good idea to check all the fixings on a bike rack to make sure nothing’s worked loose. That’s even more true on a roof rack, where you won’t necessarily notice problems when driving.
Modern bike racks are often designed to be installed tool-free, so there aren’t loads of complex things that can go wrong. But you still want to be sure that arms, clamps, bolts, locks, and hinges are all secure and in good working order.
One of the best ways to check that a load is secure is by giving it a firm but controlled push to see if it yields easily. If nothing budges under slight duress, you should be good to go.
You can also add padding either to bike frames or bike racks to cushion bikes from each other and prevent movement. Typically, people use foam pool noodles for this, as they’re ideally shaped for covering frames and tubes.
Video: Adding A Pool Noodle To A Hitch Rack
As seen in this article, there are various causes of swaying or moving bikes on bike racks. Most of these causes have remedies, which we’ve tried to provide.
You can make life easier by buying a bike rack that prevents movement in various ways. You can also boost stability with extra straps and improvised solutions.
We hope you found this article useful. You are welcome to share it with your cycling family and friends or add comments.