tongue weight capacity and using carriers for ebikes

[ebikemom]

A kind member here contacted me with an issue that I hadn't known about in getting a carrier for my ebikes, with the hope of carrying four ebikes. That is the tongue weight capacity of trailer hitches.

Here's an interesting article that explains about this issue, from a company that makes cargo carriers:
https://www.stowaway2.com/trailer-hitch-basics

Trailer hitches have different classes, each with a tongue weight capacity:


For my vehicle, there are lots of options of hitches that are possible to install, from Class II through IV. This is a good thing to keep in mind for ebike owners, to get a hitch that has enough of a tongue weight capacity to carry the intended load of cargo carrier weight+weight of ebikes.

I am now checking with my rack manufacturer (Upright Designs) to see if any additional weight capacity is required due to the configuration of the rack, beyond the weight of bikes + rack.

 

[Volts]

On my Infiniti G37 I have a class 1, good for 200 pounds, each bike a tad over 50 pounds and the carrier the same, so about 160 pounds. I read how a support strap is needed with the class I. I found the item they sell at uhaul, here :(Link Removed - No Longer Exists) I use 3, ha!

That's a good point in your last paragraph. The heaviest weight as you know should go closest to the vehicle, don't they say that kind of stuff buried in the legalise talk?

 

[rich c]

You are a braver person than I. I would not grab the lip on the trunk lid on my Infiniti G37 if I could afford one! I'm guessing that 200 pound load is based on a measured vertical load. You are talking about a load on the end of a beam, that will be greatly increased if you hit a pothole. Your 160 pounds will increase and then apply the load right to your trunk lid! Granted the load is distributed along the beam, but it is set to act like a whip when you hit a pothole. Drive carefully!

 

[ebikemom]

It is a good point that when we have a load on a carrier that is a distance from a bike, the force becomes greater than the mere combined weight of the components. What I don't know is whether the tongue weight ratings are keeping that in mind, or if we need to consider the force that will be applied above and beyond the actual gross weight when we choose an appropriate hitch.

Anyone know answers to these questions???

 

[harryS]

Tongue weight is based on the down force from a trailer right at the point of attachment. When you hang a bike rack on a hitch, the weight is out about a foot or more, so the lever effect comes into play. It's pretty iffy for us folks with class I 1 1/4" hitches. We're often barely inside the limits. I'd feel pretty good with a vehicle with a class III 2" receiver.

Which is why I use two safety straps attached to the roof rack on my VW. It's still not a good vehicle for carrying two heavy bikes. I take off the seats and batteries to save about 18 pounds.