why don’t hitch bike racks act like big breaker bars?

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Title. Looking at hitch mounted bike racks, specifically two types: racks that have a vertical bar and the bike hangs down by the frame, and racks with a horizontal platform that the wheels sit in. Think things like Thule.

I see heavy ebikes being held by heavy duty racks, or multiple MTBs on one. How is it that they are stable? I would think that – especially the hanging ones – they would act like a giant breaker bar against the hitch opening. I know that they are designed not to really wobble right and left, but how does that little 1.25 or 2” square slot stop 3-4 feet of steel bar with 30-100lbs of weight on the end from breaking loose?

Definitely not asking because I’d like a hitch rack for my bike and have trust issues. Lol. I can’t fathom how these work, and why they don’t need to be secured from the top at least.

In: Engineering

13 Answers

Anonymous 0 Comments

Steel is strong basically. The lever effect you’re talking about is present there, but the vehicle’s frame is plenty strong, and the hitches are rated for different levels. I have a class 2 hitch on my parent’s van and I can use a dirt bike carrier on it with no issue. I’ve used it for my 420 lb motorcycle as well.

Anonymous 0 Comments

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Anonymous 0 Comments

As long as the rack is installed and maintained correctly, and used within its specified weight limits, it should provide a stable and secure solution for transporting bikes.

Anonymous 0 Comments

As long as the rack is installed and maintained correctly, and used within its specified weight limits, it should provide a stable and secure solution for transporting bikes.

Anonymous 0 Comments

Consider that, in another circumstance, this hitch might be loaded up with 10,000lbs of sailboat. (Depending on the location of the axle on the trailer, this might still be several tons ~~of downward force~~ tongue weight.)

A couple of bicycles or a motorized wheelchair (I see lots of those) isn’t gonna be a problem.

Edit: corrected terminology

Anonymous 0 Comments

You are right about the forces working on the elbow of the hitch, however, steel is amazing and so is welding. In best scenario (full penetration, forces pulling on the strong side) a one inch weld will hold 1000 pounds.

Now granted the hitch elbow you’re talking Bout isn’t super thick steel with mil spec construction but it will still easily survive the weight rating on the packaging.

Anonymous 0 Comments

The receiver on my 24 year old truck is rated to tow 10,000lb with a tongue weight of +1,000lb.

The people who designed the hitch built it with the strength and safety in mind to be able to tow everything from a lawn mower all the way up to a 30-40’ long camper trailer. They had FAR more than the weight of a bicycle or eBike in mind when they engineered that hitch. Additionally, automotive hitch receivers are standardized to certain class ratings, so it makes it easier for the companies who build hitch accessories to design their equipment with a certain size hitch receiver in mind.

The steel that these hitches are made of is very thick and welded to a crossbar in such a way that it transfers the entire load of the hitch into the tow vehicle instead of twisting or breaking.

As long as you follow the instructions included with your bike rack you should have no issues with the load.

Anonymous 0 Comments

It does act as a lever, therefore it can’t hold that much weight. But some 100 pounds will not compromise some inches of steel, especially if the lever is rather short.

I can only speak for Germany, but there is a so called “Stützlast” (maximum supporting load) on the hitch and it is suprisingly low (60-100 kg for normal cars). So, depending on the weight of the bike rack itself, you can already exceed it mounting 2 e-bikes, which are considerably heavier than normal bikes.

Ofc, exceeding maximum weight, won’t break it immediately, but can influence the steering of the car or loosen the hitch, if it is an removable one. Therefore you can get a ticket if you get stopped.

It definitely cannot handle “several tons of force” like someone suggested, even if it could it would severely impact driving/steering the car.

I just looked up the specs for a class 2 hitch and it seems that it is also limited to 300lbs (~150 kgs), which you probably will exceed with a motorbike.

Anonymous 0 Comments

Well, those hitches are designed to pull up to 10,000 lbs trailers at highway speeds.

They are quite strong.

Anonymous 0 Comments

The hitch on my crossover is rated for 350lbs of tongue weight. My truck is rated for 500lbs of tongue weight. These figures are usually printed on a sticker on the hitch itself, so check that on whichever hitch you buy. That is p l e n t y for two e-bikes. The limiting factor will be the bike carrier itself. As long as your bike(s) don’t exceed that weight, you’re fine.