I am looking for a tandom axle trailer ,I found one 2 foot longer than my single axle. My axle is located 45.5 " from the rear of my trailer,I think this is the center of gravity on my boat. does that need to be the same measurement from the rear of the newer trailer to the center of the two axles to tow properly?
Thanks in advance for any and all help.
300X Mercury Racing
<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by fastcatboater »</td></tr><tr><td class="quote"> . . . does that need to be the same measurement from the rear of the newer trailer to the center of the two axles to tow properly?</td></tr></table>
You want to be working with the distance between the front of the boat and the axle setup, instead of the distance from the back of the trailer.
The current trailer's axle is close to the COG of the boat and trailer combined, off forward just enough to give the tongue weight to tow right. The approach I'd take is as follows.
I'd keep the motor in the usual stowed position through the whole process and loosen the winch tower and move it out of the way. Then I'd determine the tongue weight of the current boat & trailer - a bathroom scale will do. I'd then drop a perpindicular from the front of the boat to the trailer and measure the distance from that point to the axle. I'd position the boat on the new trailer with the front of the boat the same distance plus about 4 inches from the mid-point between the two axles. Then I'd determine the tongue weight. The end result I want is the same tongue weight with the new trailer as with the old trailer. If the tongue weight is too light, ooch the boat forward, too heavy - backward. Repeat until the tongue weight is right, then positon and bolt down the winch tower.
As I'm writing this, I ask myself what the likelihood is that during this process the new trailer & boat might tilt backward and lift the tongue because of a difference in weight distribution. Highly unlikely, seems to me. If the distibution were heavier to the back, the tongue weight would be light, but the rear axle would act like a lever arm and prevent the tongue from lifting. Going from a two axle to a single axle, on the other hand, I'd be quite concerned.
Good luck.
So many honey-dos . . . . . so little motivation
Went through the same process last Feb. I called the boat manufacturer and was able to get the info from them. The trailer manufacturer is helpful as well. At first, planned to add an axle but the manufacturer advised against that and said the trailer would not pull right. After a lot of searching and looking I ended up with a new Ameratrail made for the boat. I have been very pleased with the decision.
<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by taeheel2az »</td></tr><tr><td class="quote">
. The end result I want is the same tongue weight with the new trailer as with the old trailer.</td></tr></table>
Just asking, because I don't know for sure, but wouldn't you want the same percentage of the total boat/trailer weight on the tongue, not the exact poundage?
I realize the boat's weight is the same, but a tandem axle will weigh more than the single axle. I want to say that there should be about 10% of the total weight on the tongue. So, if the single axle plus boat weighed (whatever) 3000 lbs, there should be 300 lbs on the tongue. And if the new trailer plus boat is (whatever) 3300 lbs, wouldn't you want 330 lbs on the tongue?
This might not make a hill of beans difference, I'm just wondering...
hmmmmmmmmmm
Just thinking out loud here . . . .
The objective is to prevent oscillation between the truck and trailer & load. The tongue weight acts as a damper (sort of a brute force shock absorber) on the teeter-totter motion of the trailer & load around the axle.
Truck motion that lifts the hitch imparts angular momentum to the trailer & load. Other thing being equal, the heavier they are, the more angular momentum, the greater the dampening force (tongue weight) needed. However, the distance from the hitch to the COG is also a factor. To calculate any difference in tongue weight requiement, we'd need to know the difference in the distance from the hitch to the COG (old & new trailer).
I'd be pretty confident that these two rigs are close enough and the original setup's margin of safety is large enough that the same tongue weight would work OK.
Pretty easy to check in the real world, just drive a few miles.
Modified by taeheel2az at 5:15 PM 8/3/2011
So many honey-dos . . . . . so little motivation
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