How do Hitch Adapters and Extenders Reduce Hitch Weight Capacities

Question:

Hello, I have some questions about max tongue weight and hitch extenders and motorcycle carriers. Is there an equation or guide to figure out that actual hitch tongue weight for say a motorcycle carrier that takes into account the fact the motorcycle weight is on a lever extended 2-3 behind the hitch? In reading other questions and answers on your site there seems a glaring inconsistency so I’m trying to clarify the issue. When I read your responses to motorcycle carrier tongue weight capacity the responses indicate that if your vehicle has a 500lb max tongue weight at the hitch you can put on a total of 500 lbs of weight on the hitch with a motorcycle carrier carrier weight + motorcycle weight not to exceed 500lb. However when I read responses about hitch extenders in any length or rise your responses indicate that any hitch extender cuts the max tongue weight capacity in half. If that is the case then adding a motorcycle carrier also reduces the hitch tongue capacity. The simple physics of it dont add up. If the truck can handle 500lbs of tongue weight at the hitch the problem becomes that the motorcycle weight is extended 2-3 feet behind the hitch with the motorcycle carrier acting as a lever which would greatly increase the actual force/weight at the hitch itself. So putting 500lbs of motorcycle and carrier onto the hitch in reality must put significantly more than 500lbs of tongue weight on the hitch itself. Thanks for your time

asked by: Todd

Expert Reply:

Using an additional extender, like part # HE12, is very different than the rack, like part # K2TMC201, having a lengthy shank.

The extenders like part # HE12 are usually made of two different sized pieces of steel that are welded together. The HE12 uses a 2x2 outer dimension piece of solid steel that inserts into the hitch. Welded to the other end, is a piece of tube with a 2x2 inside dimension. That joint is a weak spot. This is a large part of why most of the extenders have a 50 percent weight capacity reduction factor.

One of the other reasons is testing. Rack and carrier manufacturers test their products to establish a weight capacity. The load the rack or carrier and test it on vehicles and testing equipment to determine what the product can safely carry. The # K2TMC201 for example is rated as high as 450 pounds depending on your tongue weight rating. The carrier was tested just as you see it, long shank and all. But there are so many adapters and extensions out there, they cannot test those. So the manufacturers of the extenders have established weight ratings or reduction factors for their products. Often times, they will provide both.

The ratings on motorcycle carriers are established when the carrier is used directly in the hitch, so even though the shank may be long, it can carry that load. When you add an adapter or extender, that is when figures have to be adjusted.

expert reply by: Patrick B