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When I connect my trailer to the bike, there is a significant downward slope of the trailer tongue. To make it level, I would need to lift the trailer ball about 2". Somewhere I read that if the tongue is not level, that it would tend to put pressure on the front wheel when breaking. Anyone have any insight on this?
 

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If I understand this correctly, the trailer is sloping forward toward the ground. If you raise the ball height 2" to level the trailer, it would NOT make the rear more apt to dive, just the opposite.

It depends how the trailer is made whether the tongue is level or not. Each one should have a recommendation of proper hitch height.
 
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You always want a trailer tongue to be as horizontal to the pavement as possible. Given the angle you are describing with having to raise the ball 2", when you brake, the trailer weight will cause the tongue to want to dive further, therefore causing the rear of the bike to dive also. This force will want to raise your front end even though it is initially diving from the braking force. All of this can cause braking control problems...I would get the proper hitch offset for the trailer you are towing.
Let me say right up front that I'm not sure about this but I would think that regardless of the attitude of the trailer tongue (when braking) the trailer weight will cause the tongue to want to dive further, wouldn't it? Therefore, it doesn't make too much difference what the attitude of the tongue is as long as there is positive weight on it. Also, let me further say IMO that the weight you are talking about would have to be excessive in order for there to be any braking control problem or front wheel lift. I guess if you take all "ifs" to the extreme (extreme tongue angle, extreme trailer weight) yea, I could maybe see some problems under extreme braking conditions but not pulling a 3-400 lb trailer with 1,100+ pounds of motorcycle and rider. I just don't think that very likely. Not necessarily fact (don't shoot the messenger) JMHO. By the way, my trailer is dead level (not necessarily the tongue) and that is as it should be.
 

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Seems to me the only thing that makes a difference is the height of your hitch ball compared to your trailer's axle height. Think about it.
 
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the further from horizontal the trailer frame and tongue are in alignment with the receiver or the ball, the more downforce or uplift the trailer has on the tow vehicle.
OK, now that seems much clearer and I can see this and certainly agree with the basic statement above. However, we are talking about 2 inches here and a couple 3 or 4 hundred pounds of trailer weight behind maybe 3 feet of tongue so whatever force may be applied even in an extreme braking maneuver is going to be negligible as far as loss of control are concerned. 2 inches over a six inch tongue would be much worse condition (angle). Still, I will agree aiming for level makes good sense but I wouldn't loose any sleep over it (here). I appreciate being corrected, just hate being wrong. :shrug:

How about level trailers, can we agree trailers should be level? :agree:
 

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Level tongue

When I connect my trailer to the bike, there is a significant downward slope of the trailer tongue. To make it level, I would need to lift the trailer ball about 2". Somewhere I read that if the tongue is not level, that it would tend to put pressure on the front wheel when breaking. Anyone have any insight on this?
I'm curious as to why your hitch is 2 inches lower than it should be. I'm assuming your bike is a Gold Wing. Does your bike sit level without your trailer being attached? Do you increase the setting of your rear shock to offset the increase in weight of the trailer and to increase the ride height of the bike? What brand of trailer do you have? Have the wheels/tires of your trailer been changed maybe an increase in size? Most of the trailer/motorcycle systems I've seen are pretty level together. Since yours seems to be much lower, try to find out what makes yours so different.
 

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But the further from horizontal the trailer frame and tongue are in alignment with the receiver or the ball, the more downforce or uplift the trailer has on the tow vehicle. When you add braking to that, it amplifies that force.
I think you've got the right idea, but....................by "horizontal" I asume you mean distance from the ground, and I agree. However, I believe what's important is that the two load bearing points (or pivoting points, if you will), the hitch ball and wheel hubs, are equal distance from the road surface. The frame/tongue could be arc shaped and the forces applied would still run in a straight line between those two points. The only thing that changes things is the load under acceleration/deceleration since it's not in that straight line. Just make sure your tongue weight is right. Most sports places carry fish scales. If in doubt go heavier ! Ride on !
Mr. Finch.....................comments, please! :popcorn:
 

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Discussion Starter #8
Trailer is America's Best (Aluma copy). The trailer sits high due to 12" wheels and a fairly stiff torsion bar suspension. I put the trailer on it's prop stand (which makes the hitch bar level) behind the bike but did not hook it up. There was no weight in the trailer or on the bike (2008 Wing) with the bike suspension at it's highest level. The hitch at that point was about 1" above the top of the ball. The ball would have to be raised about 2-3" in order for the hitch bar to be level when everything gets put together. They sell high rise trailer balls with about a 2" extension.
 

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Your trailer tongue needs to be level. Too low and it will lift the front letting the front brake lock up under severe braking. Too high and it will try to lift the rear reducing rear braking effectiveness. This is serious.
I have experience with both motorcycles and pick-ups pulling trailers.
You need to level your trailer tongue.
 

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I don't think I would put on a high-rise hitch to raise the ball. The higher the ball, the more the trailer will affect the handling of the motorcycle.

Think about accellerating out of an uphill turn. Let's say you're leaned over turning left. The higher the ball, the more force it will exert to pull you down. Same thing decelerating in a turn. The trailer will then to push you back upright.

That's my thoughts, anyway. I hope Tom Finch will weigh in here.

For what it's worth, my trailer sits perfectly level and I don't know it's there.

Glen
 

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How about pumping your schock up, If your drops in the rear with a 200 lbs passenger you pump up the schock. Well I'm guessing your tounge weight is not 200 lbs but I think pumping up the schock would level it out.
 
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Your trailer tongue needs to be level. Too low and it will lift the front letting the front brake lock up under severe braking. Too high and it will try to lift the rear reducing rear braking effectiveness. This is serious.
I have experience with both motorcycles and pick-ups pulling trailers.
You need to level your trailer tongue.
Yes, I agree but pick-up trucks pulling thousands of pounds of trailer and heavy equipment behind a vehicle that may weigh significantly less is quite a bit different than a 1200 lb motorcycle pulling a 300 lb trailer, so, perhaps the wording should be a little less dramatic.

I think the wording a bit "doomsdayish" to be used here for a motorcycle/trailer. A more accurate sentiment may be "Your trailer tongue should be level" and "...this could be serious". It's all in the numbers and if they were all plugged into some super-algebraic formula (no doubt one exists) you would most likely find that the 2 inches in question over the length of tongue and the mass being pulled will not create an effective (enough) angle of incidence to cause a problem in a panic breaking situation (at least, not in this motorcycle/trailer example).

Now, a 4,000 lb pick-up truck pulling a 12,000 lb trailer/skid loader is an entirely different example but the principles remain the same. The axle shaft of tow vehicle, trailer ball, should be the same height above the ground and the tongue should be level or parallel to the ground to prevent a higher incidence of leverage on the tow vehicle from taking over under panic breaking situation. The object being pulled is heavier than the tow vehicle (in this example) and this changes the mathematical formula greatly to a much higher degree and thus, the necessary safeguards need to be followed much more closely.

Granted, if you pulled enough weight, (but the tongue was much shorter), even that 2 inch offset could be enough to present a problem but not very likely in the specific example of the motorcycle/trailer in question. It's like painting a car, you do extensive prep work and strive for perfection but a few runs in the paint won't kill you. Neither will this 2", there is room for error.

Disclaimer: I'm certainly no mathematical genius and this summation is only my opinion so feel free to disagree with me. It is based on my purely subjective common sense and absolutely no scientific calculation whatsoever (although one probably exists somewhere). YMMV

This thread has made us all do a lot of thinking and I have certainly learned something from it! My thanks to all who have contributed.
 

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Now, a 4,000 lb pick-up truck pulling a 12,000 lb trailer/skid loader is an entirely different example but the principles remain the same. The axle shaft of tow vehicle, trailer ball, should be the same height above the ground and the tongue should be level or parallel to the ground to prevent a higher incidence of leverage on the tow vehicle from taking over under panic breaking situation.
:agree: I agree 100% with the ball and axle shaft (or wheel hubs) being at the same height. The forces applied to actually pull the trailer run in a (invisible) straight line from the ball to the axle. Regardless of the shape or angle of the tongue where it connects to the ball, those forces will remain in a straight line from the ball to the hubs. So I think the more correct thing to say is that the BALL AND AXLE should be at the same height to prevent more leverage on the tow vehicle. What screws things up is any weight that is over or under that invisible line (i.e. the load, cargo box, etc.). Any weight above that line will take weight off the tow vehicle under acceleration and add weight under deceleration. And now back to the real world - throw all your heavy stuff in the bottom, light stuff on top, make sure your tongue weight is correct and go riding! :thumbup:

:bow: Mr. Finch...........still hoping you'll jump in on this!
 

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I thought the mfg should be recommending a tongue height. Have you asked?
 

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If you would imagine a flat bed trailer with the axle and ball at the same height, and the chassis is infinitely thin, and at at the height of the axle and ball height, then there would be a straight forward, vertically neutral force on the ball while decelerating.


Now if you mounted a 10 foot erected step ladder on the flat bed and strapped a watermelon to the top step, then the geometry of the axle and ball have not changed but the location of the CG has. So now you have a down force on the ball when decelerating and an up force when accelerating, yet the geometry of the trailer tongue and hitch has not changed.

Regarding the slope of the drawbar or tongue, it is unimportant as long as it is not hinged, but rigidly attached. Note the sketch.



It is usually easy to determine the direction of forces by exaggerating the case.
 
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Thanks Tom!

We can always depend on your well illustrated drawings and exaggerated examples to clear up a confusing concept. It makes obvious sense (now) that the height and weight of the CG loaded in the trailer has everything to do with loading effects on the tongue (not the tongue angle) in accelerating and decelerating loads. Makes perfect sense.

And by that, one may also conclude that the angle of the trailer doesn't have to be nose down either. :thumbup:

I guess this would have been easier to see if I ever had the opportunity to load a ladder or watermelon in the Tailwind. :lol: So far, it's just been the ladder (4 ft). :lol::lol:
 

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Can't you just let air out of the trailer tires till it was level???

Can't you just let air out of the trailer tires till it was level???

Couldn't help it -- its snowing and I want to be on the wing! But here I am on the pc instead.


Love my piggybacker. Pulls great. :yes1:
 

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You guys make Monday mornings better!

Many years ago, about sixty years ago, when I was a paper boy, a house mover got a house stuck under the Roosevelt Avenue railroad underpass in San Antonio. It was blocking traffic for hours until another Express-News paperboy came by on his bike and suggested that they let air out of the tires. That did the trick and has been posted over the years.

There is also a scar on that underpass where a tractor trailer rig was about 8 inces too tall which brought the rig to a quick stop. I saw it with the roof of the front two thirds of the trailer sticking straight up, like a block plane shaving off a piece of lumber.

Sorry about the snow.
 
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