Can i cut my bunks down?

jitterbug127

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I was looking at my trailer last night and realized my bunks extend 2 feet beyond the back of the trailer. I was wondering if I can cut these down and be ok?

I have 5 feet of tongue to work with.
 

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jitterbug127

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I’m sure I’ll be asked this…reason I want to cut bunks down is because my boat is 16 feet. My trailer is over 20 with the bunks this way. I’d like to be able to park it in my garage I’d possible.
 

dingbat

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Check your tongue weight……most trailers are setup to handle boats in 2 ft. increments. Since you hanging two feet off the back, either your tongue weight is light or the trailer is too long to begin with

In short, you set the boat on the trailer to obtain proper tongue weight (center of gravity of the boat should be sitting roughly on the center of the rear axle) then adjust the bow stop to the boat.
 

jitterbug127

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Bunks extend past transom? Then yes. Bunks should be under transom for support. Most of the time, they extend a couple of inches past it.
Right now the bunks are flush with the transom, but my there is 5’ between my trailer coupler and where the front of my boat sits. I got a lot of tongue
 
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dingbat

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Right now the bunks are flush with the transom, but my there is 5’ between my trailer coupler and where the front of my boat sits. I got a lot of tongue
Tongue length is irrelevant. It’s doesn’t carry the load.

The important parts is to have the load sitting over the axle(s) and the proper tongue weight for the load.

How much does the boat and trailer weigh?
What is the current tongue weight?
 

jbcurt00

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Check your tongue weight……most trailers are setup to handle boats in 2 ft. increments. Since you hanging two feet off the back, either your tongue weight is light or the trailer is too long to begin with

In short, you set the boat on the trailer to obtain proper tongue weight (center of gravity of the boat should be sitting roughly on the center of the rear axle) then adjust the bow stop to the boat.
Right now the bunks are flush with the transom, but my there is 5’ between my trailer coupler and where the front of my boat sits. I got a lot of tongue
As dingbat noted, whats the Tongue weight of current setup before you change anything.
 

jitterbug127

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Just took my bathroom scale out

As far as boat and trailer weight I’m really not sure 16 foot flat bottom Jon boat with spartan trailer that measured 18.5’ from taillights to ball coupler
 

jitterbug127

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We’ll I moved it up around 20” just to see what would happen.

My tongue weight now is between 179 lbs and 286 lbs 😂. I weighted it almost 20 times and have no idea which is accurate. It’s been all over in between too.
 

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jitterbug127

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Can anyone explain why my tongue weight is so heavy? It doesn’t make sense to me unless my scale is just reading horribly. I weighed myself and it was pretty close
 

briangcc

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Simple...It's basic physics.

The trailer is a fulcrum with the trailer axle being the pivot point. As you move the boat forward on the trailer, it increases your tongue weight. To counter this effect, you'd need to move the axle forward.

**By moving the boat forward 2' you may have exceeded the capacity of your bathroom scale which is why you're getting weird readings.
 

jitterbug127

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Simple...It's basic physics.

The trailer is a fulcrum with the trailer axle being the pivot point. As you move the boat forward on the trailer, it increases your tongue weight. To counter this effect, you'd need to move the axle forward.

**By moving the boat forward 2' you may have exceeded the capacity of your bathroom scale which is why you're getting weird readings.
Thank you!

I guess I should’ve phrased my question better.

Does a tongue weight of 239 lbs for a Jon boat and trailer seem accurate? I read online tongue weight should be around 10% of total load, and I can’t see this Jon boat and trailer weighing 2400 lbs.
 

jitterbug127

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I think I’ve got it!

Weigh my boat and trailer, tongue weight should be 10% of total Number. Keep moving my winch stand back until I reach 10%, if tongue weight is still too high move axel forward.

To answer my question above I think the answer is my axel is too far forward on trailer at this point.
 

jitterbug127

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Thing about this whole thing is my trailer is about to give up the ghost anyways. I was just going to experiment with it while I can.
 

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JASinIL2006

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For a boat, 6-7% is probably OK. The 10% is more for things like travel trailers with large frontal areas and large flat sides. 10% on a boat trailer won't hurt, but a bit less won't hurt either.

If you get below 6%, that's usually when the trailer starts getting squirrelly at speed.
 

Stinnett21

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Ideally you want the rear bunk supports directly under the transom while maintaining tongue weight as described above. If the bunks protrude past the transom feel free to cut them off. The weight of an outboard, especially on an aluminum boat, can and does often cause the hull to bend/distort creating performance characteristics you don't want.
 

jitterbug127

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My tongue weight is already too darn high, so I am not going to cut anything down. I have decided to moved everything back to where it was.

My next step (hopefully tomorrow or next week) is to get a weight of my boat and trailer to see how much that total is. I think I am going to have to move my axel forward to tip the scales before I can cut the boat down. How to balance this is going to be another Youtube Video.

I suspect my rig weights 1200 lbs at most, and I think that's probably an over estimate.

Anybody got a guesstimate of what this thing weighs? Plywood floors in the boat.
 

JimS123

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A tongue weight that is too low is dangerous. I don't see why a tongue weight can ever be too high, unless the tow vehicle can't handle it.

I solved the garage problem with my first boat. I cut the drywall out between 2 studs, and then parked the boat with the motor sticking in the hole. Grandpa solved the problem by cutting a hole in the back of the garage and then building a shed that protruded into the back yard, just big enough to contain the entire motor.
 
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