Trailer nose weight

bmb779 · 15 July 2015, 22:17

hi, when I bought my Rib it had none or very little nose weight,by adjusting bunks and winch post and moving rib forward I got it to a reasonable weight. I now want to fit a skimming transducer but because the boat is further forward the transducer is fouling the bunk.
Would it be ok to move boat back so transom is not going up as far as bunks,adjust the winch post and shorten the trailer to achieve a decent nose weight?

jonp · 15 July 2015, 22:52

You could just fit an adjustable transducer mount and simply slide it up out of the way when needed. The weight on the front of the tow-ball should be around 10% of the whole rig weight ie a 1 ton boat outfit should be putting around 100kg of downward force on the hitch easy to test with bathroom scales if your setup isnt too big. (or so Ive always been told)
Jon

Superjetjim · 15 July 2015, 23:13

You need hitch weight, can get twitchy without..

Pikey Dave · 16 July 2015, 07:16

Can't you shorten the bunk? The face of the transducer only needs to be around 6mm lower than the hull. I'd be looking at curing the problem at source rather than upsetting the whole rig. That's curing one problem & creating another.

beamishken · 16 July 2015, 07:53

Move the axles back to achieve the nose weight, that has the same affect as moving the boat forward be a shame to start cutting lumps off the trailer

kerny · 16 July 2015, 07:56

Quote:

Originally Posted by beamishken

Move the axles back to achieve the nose weight, that has the same affect as moving the boat forward be a shame to start cutting lumps off the trailer

That's the one. :thumbup:

bedajim · 16 July 2015, 08:36

Quote:

Originally Posted by jonp

The weight on the front of the tow-ball should be around 10% of the whole rig weight ie a 1 ton boat outfit should be putting around 100kg of downward force on the hitch easy to test with bathroom scales if your setup isnt too big. (or so Ive always been told)
Jon

So a 3.5 tonne trailer has around 350 kg on the hitch

Best to look at the car towing rating and the hitch rating to get an idea of maximum load on the hitch.

paddlers · 16 July 2015, 09:12

I must admit I've never used scales to measure the nose weight on my SBS trailer. I fitted a slider to lift the transducer out of the way and tend to load the boat for the holiday by checking with a frequent lift at the front. I did move the axle and winch post to provide probably 20 lbs of positive weight at the front but if I fill the petrol tank I add another 120 Kilos !

Superjetjim · 16 July 2015, 09:38

Max nose weight on the average family car is 75KG, I personally aim for 40KG so it's manageable.

jyasaki · 16 July 2015, 14:27

Tongue weight should be in the 7-10% range. Too light, and the trailer becomes unstable while towing; too heavy, and you load the tow vehicle too much (which isn't much of a problem on heavier vehicles, but can affect steering near the TV's limit.)

As Beamishken said, if you can't move the boat, move the axle.

jky

bedajim · 16 July 2015, 14:36

Quote:

Originally Posted by jyasaki

Tongue weight should be in the 7-10% range.

jky

On a 3500 kg trailer???

beamishken · 16 July 2015, 16:04

Quote:

Originally Posted by bedajim

On a 3500 kg trailer???

Different ideas in USA!

I always thought 75kg was the max recommend nose weight untill I read a thread on here & I double checked my 3500kg goods trailer has a max nose weight of 150kg on the hitch so clearly can't get to 7% let alone 10% my hilux pickup rated to tow 2700kg has a max nose weight stamped on the tow bar of 120kg so you can't get anywhere near 7 or 10%
Personally if I'm loading my goods trailer I watch the suspension on the tow car & watch untill it sits down a little & that's good enough with a boat if it's a sizeable boat if I struggled to lift the front of the trailer then that's usually ok
If you get problems with snaking and you have 75kg on your hitch then there is a good chance that there is something else wrong with the combination

dave3235 · 16 July 2015, 16:48

Quote:

Originally Posted by jyasaki

Tongue weight should be in the 7-10% range. Too light, and the trailer becomes unstable while towing; too heavy, and you load the tow vehicle too much (which isn't much of a problem on heavier vehicles, but can affect steering near the TV's limit.)

As Beamishken said, if you can't move the boat, move the axle.

jky

Hi all

Why not just put some ballast at the front in your boat.

bmb779 · 17 July 2015, 09:18

Quote:

Originally Posted by dave3235

Hi all

Why not just put some ballast at the front in your boat.

ThAt would mean the boat would be slower and the transducer would still foul on the bunk. The trailer is too big for the boat so after advice from a trailer company I'm going to move boat back to end of bunks and have drawbar shortened to give me a nose weight of approx 50 kg.

dave3235 · 17 July 2015, 09:42

Quote:

Originally Posted by bmb779

ThAt would mean the boat would be slower and the transducer would still foul on the bunk. The trailer is too big for the boat so after advice from a trailer company I'm going to move boat back to end of bunks and have drawbar shortened to give me a nose weight of approx 50 kg.

Hi

When I say ballast,what mean is when towing for example if you have a caravan you can't move the shell up and down the trailer,The stuff you have carry in the van your suit case's awning you would move to the front to the front to give you the tow hitch weight .

beamishken · 17 July 2015, 14:23

Quote:

Originally Posted by bmb779

ThAt would mean the boat would be slower and the transducer would still foul on the bunk. The trailer is too big for the boat so after advice from a trailer company I'm going to move boat back to end of bunks and have drawbar shortened to give me a nose weight of approx 50 kg.

Seems a shame to chop down the trailer!
Removing a chunk from the front might not achieve what you want as the gain will be marginal
Moving weight forward or bunks forward or pivot point (axle) rearwards is the best option
It's also easier to reverse a trailer with a longer draw bar

jonp · 18 July 2015, 04:09

Quote:

Originally Posted by bedajim

So a 3.5 tonne trailer has around 350 kg on the hitch

Best to look at the car towing rating and the hitch rating to get an idea of maximum load on the hitch.

Sorry about the misinformation you must have quite different rules in the UK but thats how things are in this part of the world (like the US too) Frequently Asked Questions - Frequently Asked Questions - hayman reese

I didnt relise the person asking the question had a 3.5 ton boat as his bio says 3m+ with a 20hp outboard.

Jon

bedajim · 18 July 2015, 07:42

Quote:

Originally Posted by jonp

Sorry about the misinformation you must have quite different rules in the UK but thats how things are in this part of the world (like the US too) Frequently Asked Questions - Frequently Asked Questions - hayman reese

I didnt relise the person asking the question had a 3.5 ton boat as his bio says 3m+ with a 20hp outboard.

Jon

You quoted 1000kg not many cars in the UK can have 10% of that weight on the tow hitch.
The only way is to see what the tow car is rated at and set nose weight accordingly

jonp · 18 July 2015, 09:16

Quote:

Originally Posted by bedajim

You quoted 1000kg not many cars in the UK can have 10% of that weight on the tow hitch.
The only way is to see what the tow car is rated at and set nose weight accordingly

Many of our cars like the US are v8 or v6 and easily capable of towing with 100kg even much more on the tow hitch, though most boaties have 4x4s for towing and launching their boats.

100kg on the hitch is only like having one average sized person these days sitting in the boot or two bags of cement. A ford falcon can tow up to 2300kg.Top 10 vehicles for towing: Car Reviews | CarsGuide

Sorry Im not quite getting your point but 1 ton or 1000kg would work out at 100 kg on the tow ball (10%), my mates with boats close to 4 tons use Ford f350s to tow them and have around 350-400kg on their tow-balls. The utility vehicles in the link are built to cary at least 1 ton in the rear tray, some more.

Jon

bedajim · 18 July 2015, 10:04

Quote:

Originally Posted by jonp

Many of our cars like the US are v8 or v6 and easily capable of towing with 100kg even much more on the tow hitch, though most boaties have 4x4s for towing and launching their boats.

100kg on the hitch is only like having one average sized person these days sitting in the boot or two bags of cement. A ford falcon can tow up to 2300kg.Top 10 vehicles for towing: Car Reviews | CarsGuide

Sorry Im not quite getting your point but 1 ton or 1000kg would work out at 100 kg on the tow ball (10%), my mates with boats close to 4 tons use Ford f350s to tow them and have around 350-400kg on their tow-balls. The utility vehicles in the link are built to cary at least 1 ton in the rear tray, some more.

Jon

Have a look here for a lot of UK spec cars

http://www.caravanclub.co.uk/media/1...oseweights.pdf

3.5T Universal Coup with 32mm Pin - Dixon-Bate