Hi regors,

Just curius, Did you happen to use AutoCad to do your trailer design layout? If so can I get a copy of your .dwg files on this project.

DennisB

The weight of the loaded trailer is not born fully on the hitch. Nor is that weight felt as full dead weight in the lateral pulling of the trailer.

The weight at the hitch, or the tongue weight may be greater than 15lbs., but may not be much greater. That weight is felt as vertical load on the hitch structure and the vehicle it is mounted on. The majority of the weight of a properly designed trailer is supported by the axle(s)/wheel(s). The farther back the axle the greater the tongue weight (properly distributed load).

The rolling wieght, which is felt along the longitudinal axis of the bike is only significant at startup when the full mass must be put into motion. But after the full mass is moving the wheel(s) of the trailer aid in moving the mass.

Think about trying to push a wheel barrow. All of the weight is in between the wheel (far in front of the weight) and the handles (far behind the weight). If you notice most of the weight is born on your arms. Getting it started is the hard part, but once rolling it is fairly easy to keep it rollling barring any obstacles. Now try to push the wheel barrow without a wheel. The wheel of the wheel barrow like the wheels on a trailer remove a very big amount of the friction required to move something laterally.

A fully and properly loaded trailer weighing 160 lbs. should be balanced resulting in minimal vertical weight on the hitch. A properly designed trailer should be aligned and it's running gear should minimize the rolling resistance (drag).

Thanks for your fine explanation. Some people might not have known that you can take the load off the tongue by putting the weight near the rear of the trailer. Taking all the weight off the tongue can actually change the vertical from a downward force to an upward force. That is not good if you are pulling a load with an 18 wheeler or a two wheeler. You have to know basic things about capacities and the load vectors when using a trailer.
Your explanation was a big help in explaning that.

Thanks again

(By the way... how old is your daughter in the avatar with you?

Dale,
I understand and agree with everything you have said.
It was my understanding however that a certain amount
of weight is actually necessary on the tongue to insure
the towing vehicle can maintain control of the trailer.

If I hit a large bump with a trailer attached, the wing will go up
and come down before the trailer does. Since at some point
the trailer will be higher than the bike won't it be shifting its
weight down on the tongue until the two land at the bottom
of the bump and equalibrium is restored?

Dan,

You are correct - a certain amount of weight is necessary on the hitch point to maintain control.

I don't think the momentary downward forces are so great as to cause most of the weight of the trailer to be transferred to the hitch point. Remember the wheel(s) and axle(s) will also absorb some of that weight. The weight while the trailer is airborne is not felt until it touches down again. At that time the weight is shared in proportion between the hitch point and the wheel(s)/axle(s).

Gary,

I almost missed your post, glad I scrolled up. I am so happy that you noticed that beautiful woman. I was pondering her earlier this am and realized how much I am in love with my wife. she is a strong, gracious, loving, and funny woman. I love to hear her laugh - it really brightens my day.

Sorry DennisB for the hijacking of your thread.

When designing and building your own trailer for the silverwing, you have one big advantage over just going out and buying someone else's pre-fab unit. You have the advantage of loading your cargo box, gear, cooler, spare tire, or what ever into/onto your new trailer frame with a weight scale under your hitch end with the tongue parallel to the ground. By moving the box and load back over the wheels or closer to the hitch you can adjust the weight on the hitch ball. That's what I'm planing on doing when this phase of my trailer building is needed.

DennisB

That's OK Dale...LOVE AND HAVING FRIENDS are the most important things in this big world.

DennisB

The first picture looks like my friends bike and the trailer he built . If it is his it weighs 180 lb. loaded . He towed it 3000 miles .The hitch that looked like the one in your picture failed after 900 miles .The company he bought it from flew in another one and he was back on the road the next day . It was good for the rest of the trip . He has sold the bike to my Buddie and we are towing it and my bike to Florida in Feb. The trailer had no ill effects on the bike .I know this guy pretty good and I would say that he was probably doing 75 MPH with that trailer behind him .

Question from me!

When pulling a trailer on your scooters are there stronger suspension struts available or do you simply set the suspension to the hardest setting?

When pulling trailers in cars there are stronger struts available to support the extra weight imposed.

Hi Waspie,

Since the hitch attaches to the swing arm of the scooter, there is no need for a stronger suspension system on the bike.

DennisB

Dennis he never had any more trouble with the second one .He moved the hitch to a motor cycle .I am no t sure what kind .

A company called hagon makes products for the rear end of the Silverwing,
and Hyperpro makes what you need for the front end.

Dan

Doug, I get that to...I call it a BRAIN FART.

Hey Dennis, I created my Trailer Plan in a program called "PhotoShop"
This frame was designed for the "Thule Sidekick Box". If I had it to do all over again I would reduce the width by 2", this would bring the sides in closer to the box and also reduce the overall weight.
I would also like to point out that your trailer tongue length as
measured from the axle forward should be between 1.5 & 2 times the width of your axle wheel center's. This will stop any fish tailing and your trailer will follow like a dream.

Good Luck With Your Project

I have several friends who pull some pretty large trailers with their Goldwings, one of them has a 500lb camp trailer. The big 'Wings handle the loads well though I wonder about the load on their brakes with a 500lb. trailer and riding two up.
There are a couple of reservations I'd have with trailer hitches such as those shown on this thread though. First off it looks like there's only one little bolt carrying the tongue weight in shear, that's the bolt on the lower right side. That one is going to get some pretty high shear loads on it due to the fact that the hitch is riding on an unsprung part of the scooter. Sudden shock loads can be pretty high. The only other reservation I'd have is the fact that the cross over tube is also going to have some torque loading due to the fact that only the right side, that lower bolt, is holding the hitch up. Other than thre point hitches on tractors the only trailer hitches I've seen used on automotive applications all attached to a part of the vehicle that was suspended by the vehicles suspension system, not on the unsprung parts.

regors, thank's a bunch for your drawing. That will come in handy to me and alot of other people on this forum if they decide to go this rout. One more thing I need to ask you about is the trailer suspension. What did you use?

Thank You very much

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exavid, Thank's for your observations. The shear bolt (6mm) was a concern of mine also. I replaced it with a hardened bolt and the rest of the hitch should just be fine the way it is.

DennisB

I really have no doubts your hitch will serve it's purpose well. I tend to overbuild things anyway, if I'd built the thing the bike would have to have dualies on the rear end.

Dennis, I used Torsion Axle's which gives you independent suspension,
I picked them up from a company in Texas they where the lightest rated one's that I could find, rather pricey but I made up for that by getting the Thule top box for less than half price.

Hi regors, Thanks for getting back with me. I've been looking at torsion axle's but never found a pair that would be light enough duty for this application. Texas is just South of my location and would be a nice drive and a great state to visit again.

Did you install a utility light in the inside lid of the Thule box?

Hi MaxB,

On the Harbour Freight trailer, did you find it necessray to change the tires out to a higher rate of speed type? Where they the 8" or the 12" tires. If they where the 8" how did they do?

Hi Bill, Yes I can but I'm not there at this moment.

The axles I used were adjustable by adjusting the angle between the arm and the axle mount. Straight up rated for 500lbs, on maximum angle 325lbs.
Either way works great for me.
My tongue weight is 15lbs loaded.
Load your trailers carefully.

I would like to take this moment to thank all of you for your sharing and your contributions of knowledge and experiance to this subject.

We all get a little smarter and wiser when good people like you'll help one another to get projects completed.

I know I will be referring to all this great information as time goes by.

Thanks again,