# Adjusting the Tongue Weight

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The tongue weight of the trailer seemed
excessive, and with the aid of a household scale proved to be 280
lbs.!!! Although this was still within the 5-10 % of total weight
guideline; considering I had an extendable trailer tongue, I felt
like it was too much. In order to extend the tongue of the
trailer, and avoid buckling the extension bar, the trailer tongue
weight should be kept to a minimum. At a tongue weight of 280 lbs.,
I was running the risk of buckling the extension bar.

I wanted to bring the tongue weight down more
towards the 5% range. Considering the total load (boat &
trailer) is about 3100 lbs., I wanted to shoot for a tongue
weight of 160 lbs. (+/-). The tongue weight would be reduced by
moving the axle assembly slightly forward.

#### Outlined below is the formula I used to
determine how far to move the axle assembly.

Diagram of Trailer
Weight & Balancing

__Adjusting Tongue Weight:__

1) I measured weight at the ball/coupler using
a household scale.

2) I estimated the total weight of load (boat +
trailer), based on the manufacture's data.

3) I measured the distance from the ball to the
rear axle and called that distance "C".

4) I found the Center of Gravity by solving for
"A" and "B".

I assumed the trailer is not moving, so all
forces must be equal. Therefore, I knew the following to be true.
. .

(280 * A) = (2820 * B) and (A + B) = C=180
inches

Solving for A and B, . . .

A = ((2820 / 280) * B) or "A"
is about 10 times the distance of " B ".

A = 10 * B and (10 * B) + B
= C so, (11 * B) = 180 inches

B = 16 inches , A = 164 inches

Adjusting (reducing) the tongue weight was done
by moving the axle forward, i.e. shortening "B".
"A" will stay the same, as I will not be moving
the C. G. (note that the overall measurement "C" will
be reduced as well). Using the equation from above and plugging
in my target tongue weight (160 lbs.), I calculated the new
"B" measurement . . .

(160 * A) = (2940 * B) or (160 lbs. * 164
inches) = (2940 lbs. * B inches)

B = 9 inches So, the axle needs to be moved forward 7 inches (16
- 9).

I was careful to maintain the axle alignment
when I moved the axle forward.

The final results, as checked by my
household scale, was 155 lbs. (exactly 5%). If I needed more
tongue weight for towing (which I did), I could store the rudder
assembly in the V-berth, bringing the tongue weight to about 190
lbs.

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