Vehicle/Trailer Load Balancing. Other solutions.
I've not tried load balancing bars, but the effect seems to be that of 'transferring weight from the rear
wheels to the front of the tow vehicle, thus ensuring efficient steering and braking' (quoted from the article).
Elsewhere there is a recommendation that tow bar load should be 10% of the trailer weight; so a 2000Kg caravan should have a 200Kg tow bar load (vertically).
For a
well balanced rig it would seem important to have 2 parameters about right: the tow bar weight and height (the latter to match the trailer tow hitch height) plus the relative weights of towing vehicle and trailer within regulations.
Air bags on the rear axle of the drive axle also seem to be a common solution but this suggest that tow bar weight might be too much anyway.
However, I've never seen the solution that I've adopted; I don't have an engineering background but chose the following as an alternative solution (suggested by me, fitted by ARB); and it seems to work very
well....
I have a 1000Kg offroad dual axle camper trailer (with heavy duty leaf springs and linked for trailer load sharing) , and have fitted airbags to the front axle OF THE TRAILER. By increasing the pressure in these airbags, the balancing point of the trailer moves backwards and adjusts the towbar load, and consequently the height. The trailer is fairly
well balanced currently so on the open road I have just 10psi in the bags, but I plan to add weight in the form of a trailbike, and maybe more storage, onto the drawbar (it's a long one), so would just add more air.
The setup has the added advantage that enough air (about 70psi in my case) will lift the rear axle clean off the ground; handy for those tight reverse turns that scrub tyres in a dual axle setup. It makes the tow bar weight too light, but I wouldn't drive far or fast with it anyway. Handy also for decoupling: takes the load off.
I also went one step further and had airlines fitted from my vehicle compressor to the trailer via a control switch & gauge; so the trailer air bag pressure can be adjusted from the cab; even while moving! I'd be interested to know if anyone else has seen such a solution, whether it might work for heavier caravans, and whether anyone has seen a device for measuring actual towbar load.