Towing Capacity With Dual Hitch Receiver Adapter - Boat And Four Bike Rack  

Question:

Expert Reply:

I understand why someone would want to take their camper, boat, and four bikes RV'ing simultaneously! It sounds like quite the adventure! Let's talk about how it might be possible to make this work.

You are correct that if the loaded bike rack is 300 lbs. and your tongue weight capacity is only 500 lbs., you only have another 200 lbs. to play with. It appears that your boat's tongue weight is not known to you. Typically this number is going to be 10-15% of its gross trailer weight, in your case a range of 650-975 lbs. The first thing I would advise is for you to do is to determine the exact tongue weight for your boat. If you're in need of a tool that will measure this for you, the etrailer Trailer Tongue Weight Scale # e99044 will help you. You likely will not be able to ascertain an accurate hitching solution without this information, and safety should always be your first priority.

It also sounds like you have a motorhome that has a Class III trailer hitch mounted to the rear with a 2" receiver tube. Assuming your boat's tongue weight is somewhere between 10-15% of its gross weight (650-975 lbs), which would be typical, I simply do not recommend pulling your boat with this hitch. Class III hitches have tongue weight capacities that can range between 300 and 800 lbs, and it sounds like your specific hitch is toward the lower end of that spectrum at 500 lbs. Unfortunately that is simply not enough to pull your boat safely. If the boat was the only thing you were looking to pull, it might be possible to do so with a stronger Class III hitch than the one you have.

However, as long as the hitch you're trying to use has enough tongue weight capacity, it should be possible to use a dual receiver adapter such as the Roadmaster # RM-077-8 to pull both your boat and loaded four-bike rack simultaneously! Looking at your tongue weight situation, with this application in mind, I don't recommend anything less than a Class V hitch.

This presents you with two options: you can look into upgrading the hitch on your motorhome to a Class V hitch (which may or may not be possible), or you can look into a different towing vehicle that either has or is compatible with a Class V hitch. If you were to obtain a vehicle with a Class V hitch (or if you're able to modify your motorhome with a new Class V hitch installation), then there's some important things to keep in mind with the dual receiver hitch adapter you mentioned.

Any time you use an adapter with a hitch receiver, the tongue weight capacity is reduced by 50%. This is true whether you're using a dual hitch receiver adapter like the Roadmaster or another type of hitch adapter (such as a reducer, expander, or extender). Let's assume you upgrade your rig and your new Class V Hitch has a maximum tongue weight rating of 2000 lbs. With the dual hitch receiver adapter, this would be reduced to 1000 lbs before you hook up the boat and bike rack. If your boat's tongue weight is 650 lbs and your fully loaded bike rack is 300 lbs, then this application would work safely.

expert reply by: Aaron A

0