MacGregorSailors.com

A fascinating short video on why weight distribution matters so much for trailers.

This is the season where many boats will be trailered to their winter storage location.
Well worth knowing what could happen with big outboards on the back.

https://www.facebook.com/dunlaoghairema ... 689527395/

Fascinating video. I always wondered how weight distribution and trailering works.

Here's another linky

https://www.youtube.com/watch?v=4jk9H5AB4lM

For those that use a heavier tow vehicle like a truck, the dynamics would change. And some of us even used dual axle trailers which would also affect the results. Yes, very interesting.

Many years ago I witnessed a vehicle Towing a boat with an outboard on the end of it, and the swaying back and forth became so bad that the boat and trailer flipped off the highway and rolled over several times in the ditch. I was directly behind and had a direct view of the whole incident. This YouTube video reminded me of it.

The calculation is 10% of trailer weight on the tow ball for safe towing,

So if your all up trailer weight is 1700Kg (3740lbs) then the weight at the tow ball should be 170Kg or 374lbs.


You can change the weight distribution by moving the axle or the position of equipment you have loaded in the boat.

Basically anything heavy should be packed in the front of the boat

sailboatmike wrote:The calculation is 10% of trailer weight on the tow ball for safe towing,

Well, it depends on cars and trailers. Here in Europ most trailer are around 80kg round.

My stock alu trailer with EU tongue has max 100kg. Max total weight ist 2500kg, dual axle. So you cannot generalise.

3500kg trailers go to 150kg tongue weight...

kurz wrote:

sailboatmike wrote:The calculation is 10% of trailer weight on the tow ball for safe towing,

Well, it depends on cars and trailers. Here in Europ most trailer are around 80kg round.

My stock alu trailer with EU tongue has max 100kg. Max total weight ist 2500kg, dual axle. So you cannot generalise.

3500kg trailers go to 150kg tongue weight...

I notice the allowable ball weight on a lot of the european cars is very low, HOWEVER this does not change the rule of thumb for safe towing, it really just means you shouldnt tow such heavy long thing.

The 139Kg motor on my X is 33 feet behind the tow hitch, thats a long way and makes the chances of the pendulum situation like in the video much higher unless you have decent tow ball weight

If you do not exceed the allowed 80kmh you stay safe.

As you go to 90kmh you can feel how the trailer starts swaying. But NOT in 85kmh range...

kurz wrote:If you do not exceed the allowed 80kmh you stay safe.

As you go to 90kmh you can feel how the trailer starts swaying. But NOT in 85kmh range...

I have traveled 100 kmh on American interstate highways and been the slowest thing on the road. Maybe except for the Amish.

Phil M wrote: ...I have traveled 100 kmh on American interstate highways and been the slowest thing on the road...

100 kmh? ...That's the breakdown lane!

K9Kampers wrote:

Phil M wrote: ...I have traveled 100 kmh on American interstate highways and been the slowest thing on the road...

100 kmh? ...That's the breakdown lane!

I've had "Mistress" up to 75mph coming down Raton Pass, N.M., but after that momentary elation of knowing I had the fastest boat on the road, I slowed down and wondered what the heck I was thinking.....

I've found towing at 60 mph is stress free and sway free. It does mean right lane on the Mass Pike, but that's fine too.

Catigale wrote:I've found towing at 60 mph is stress free and sway free. It does mean right lane on the Mass Pike, but that's fine too.

Same here. 60 and under is very comfortable.

They raised the speed limit to 80 here on the Interstate, so I'm in the right lane all the time. I simply don't like fast speeds towing anything.

--Russ

As an aside, most trailer service tires (which we should be using on our boat trailers instead of auto tires) are speed rated for only 55 MPH. I'm sure that there is a safety factor in the engineering, but I'm not sure that 75 MPH is still within that safety factor!