trailer bounce

[andyrmilwaukee]

I have a small fishing boat, that i had to redo the trailer for, I had to replace the leaf springs in the process, I already removed one plate from the springs to soften the ride and that has helped however, when i hit bumps sometimes it bounces the motor pretty good, I want to take it camping and load the boat with a couple extra hundred pounds of weigt, should I postiion the weight forward or back to stop this bouncing?

 

[nate1220]

Re: trailer bounce

The bouncing could be caused by too high of a tire pressure. Also you should load as evenly as possible but if you can't you should put more weight in front of the axle, but keep the bulk of the weight over the axle.

 

[kenmyfam]

Re: trailer bounce

Experiment. Throw a couple of hundred pounds of "stuff" in there and go for a ride. Try with the bulk of the weight over the axle to begin with.

 

[roscoe]

Re: trailer bounce

Actually, bounce is more likely caused by under inflated tires.

Boat trailers do not have real active suspensions, they need properly inflated tires or they will blow out.

Put most of your heavy items over the axle, or slightly forward, will add a little tongue weight but that is better than making it "tongue light."

 

[nate1220]

Re: trailer bounce

Actually bounce is most likely caused by over inflated tires, I am a mechanic and a tire tech so I have alot of experiance in this area. under inflated tires bounce but not in the same way, under inflated tires will give you severe trailer sway and make the trailer hard to control at speed. Most tires on small trailers are rated for 50 to 65psi but with a light weight boat they actually only need to be inflated to 35 to 45 psi.

 

[oldjeep]

Re: trailer bounce

Actually bounce is most likely caused by over inflated tires, I am a mechanic and a tire tech so I have alot of experiance in this area. under inflated tires bounce but not in the same way, under inflated tires will give you severe trailer sway and make the trailer hard to control at speed. Most tires on small trailers are rated for 50 to 65psi but with a light weight boat they actually only need to be inflated to 35 to 45 psi.

Trailer tires are supposed to be inflated to sidewall pressure, and under inflating them can cause premature failure - especially on bias tires.

 

[nate1220]

Re: trailer bounce

if you inflate to max psi you may get a bounce because you are over inflated for the load you are carrying. Do you iflate your car tire to max psi?

 

[nate1220]

Re: trailer bounce

you want the width of the tread to sit flat from side wall to side wall

 

[oldjeep]

Re: trailer bounce

if you inflate to max psi you may get a bounce because you are over inflated for the load you are carrying. Do you iflate your car tire to max psi?

Nope, but my truck has LT radials which are spec'd for a range of acceptable pressures. My trailer has ST bias trailer tires which the manufacturer says to inflate to sidewall pressure.

 

[nate1220]

Re: trailer bounce

in the end it comes down to what works best for you.and yes your truck tires have an acceptable range depending on the vehicle and load that is on them that is what I am trying to say. You don't have to inflate them to max psi for a light load the low side of the pi range may be correct.

 

[roscoe]

Re: trailer bounce

Tire tech or not, you are going against the advice of the manufacturers and engineers. Allowing the sidewalls to flex causes extra heat to build up in the tires. Ever see a tire at these air pressures hit something, like rough railroad tracks, or a large pothole?


Andy, at trailer has a stiff suspension without shocks, it should not be soft, the springs rarely flex while going down the road. The springs are there to carry the load. Be careful in removing spring leafs, or you risk breaking the remaining springs.

 

[nate1220]

Re: trailer bounce

If the tire is inflated within the recommended range how is that going against the manufacturers advice, by the way how many manufacturers have you personally spoken to and asked these types of questions to, I know I do on a weekly basis. I am just stating that the max psi rating is not always the best pressure to run a tire at. The max psi is not the manufacrurers recommended pressure anyway, it states the max safe operating pressure of the tire.

 

[oldjeep]

Re: trailer bounce

If the tire is inflated within the recommended range how is that going against the manufacturers advice, by the way how many manufacturers have you personally spoken to and asked these types of questions to, I know I do on a weekly basis. I am just stating that the max psi rating is not always the best pressure to run a tire at. The max psi is not the manufacrurers recommended pressure anyway, it states the max safe operating pressure of the tire.

Can you point out some source of information that says that ST tires should not be inflated to the max pressure? Or any type of trailer tire that actually lists a range rather than a single value?

This is the recommendation that I have always found in print:
http://www.discounttire.com/dtcs/infoTrailerTireFacts.dos

Inflation
?Always inflate trailer tires to the maximum inflation indicated on the sidewall.
?Check inflation when the tires are cool and have not been exposed to the sun.
?If the tires are hot to the touch from operation, add three psi to the max inflation.
?Underinflation is the number one cause of trailer tire failure.

 

[IES99]

Re: trailer bounce

Can you point out some source of information that says that ST tires should not be inflated to the max pressure? Or any type of trailer tire that actually lists a range rather than a single value?

This is the recommendation that I have always found in print:
http://www.discounttire.com/dtcs/infoTrailerTireFacts.dos
Inflation
?Always inflate trailer tires to the maximum inflation indicated on the sidewall.
?Check inflation when the tires are cool and have not been exposed to the sun.
?If the tires are hot to the touch from operation, add three psi to the max inflation.
?Underinflation is the number one cause of trailer tire failure.

^^^^^^^^^
Thanks for the great info and URL. I have always kept my trailer tires at the maximum pressure recommended on the side wall, a much different approach than I take with the tires on the car and Jeep.

First a disclaimer: my family has been in the tire business for 60 years. I was always taught that underinflation is the most damaging thing you can do to tires in general use.

With regard to the OP's bouncing: sounds like a little more weight over the axle would retard that to some degree.

 

[IES99]

Re: trailer bounce

Actually, bounce is more likely caused by under inflated tires.

I see that you have never tried to play basketball with an underflated ball. No bouncy.

 

[roscoe]

Re: trailer bounce

by the way how many manufacturers have you personally spoken to and asked these types of questions to,I am just stating that the max psi rating is not always the best pressure to run a tire at. The max psi is not the manufacrurers recommended pressure anyway, it states the max safe operating pressure of the tire.

Only 3 trailer manufacturers, and 1 tire manufacturer, and several tire manufacturer documents.

And uh, no, thats not what you said.
You said "bouncing could be caused by too high of a tire pressure", which just flies in the face of conventional wisdom.

"Carlisle Tire and Wheel recommends adjusting the air pressure to the Maximum pounds per square inch (PSI) listed on the sidewall of the tire. If you inflate the tires to less than the maximum inflation level, you dramatically reduce the load carrying capacity of the tire."

"Keep your tires air pressure at the Maximum PSI recommended on the sidewall of the tire."

"The most common cause of tire problems is under-inflation. It is estimated that a trailer tire that is 20 percent under-inflated will cut 25 percent off its lifespan; one 30 percent under-inflated will reduce its term by 55 percent. Under-inflated tires also affect fuel efficiency by as much as 10 percent due to added drag.
More important, under-inflation puts undue stress on the tire, producing irregular wear at best. At worst, under-inflation causes complete failure that can result in an accident. Abnormal tire flexing occurs when a tire doesn?t have enough air, which can generate an excessive amount of heat will exceed the tire?s capabilities and cause the tire plies to sepa- rate or result in a blowout."


"Inflation
Always inflate trailer tires to the maximum inflation indicated on the sidewall.
Check inflation when the tires are cool and have not been exposed to the sun.
If the tires are hot to the touch from operation, add three psi to the max inflation.
Underinflation is the number one cause of trailer tire failure."

Here's something else we can .... discuss.

"Speed
All "ST" tires have a maximum speed rating of 65 mph."