Is it wise to tow up to 100% of kerb weight?

[Dustydog]

Fully agree Colin
In 8 years with ATC I can't recall it ever kicking in but I know it is operational.
A well loaded van does not really need ATC. ATC will not make the "pressure wave" effect of a coach disappear.

 

[Raywood]

Hi JTQ,

Excellent comment, well argued reasoning about the OPs potential outfit.

I totally agree about the need for a revised guidance model, and I am still trying to devise a more reliable matching scheme. The big problem is the dynamics of a caravan can be so readily affected by how it's loaded. A well loaded big caravan can be much easier to tow than a poorly loaded small one. We also cannot dial in the biggest variable if all - the driver.p

Because there are too many uncontrolled variables (driver, road and weather conditions etc) it will be impossible and unsound to suggest any outfit combination is SAFE. So it's more a question of identifying unsuitable combinations, but based on technical grounds rather than the ad-hoc unscientific current notional towing ratio.

I agree that a technical based system would be best but given the infinitely variable number of combinations I cannot see how we can achieve this so 85% for beginners is a reasonable idea with more experienced drivers going higher is the best we can do.

 

[Danddandy]

Regarding the ATC on a technical point, it operates both sides simultaneously rather than one side or the other.

 

[Martin24]

No it isn't. At 100% you're getting very close to the van having control of the car.

 

[colin-yorkshire]

No it isn't. At 100% you're getting very close to the van having control of the car.

this is the problem with assuming theoretical figures are set in stone, when in fact reality dictates a increase in ratio will have little effect, given all the other parameters one has to take into account.

the assumption that the tow vehicle will be used when at it's lightest. while the trailer will be loaded to the maximum is flawed. as is the assumption that weight alone governs how the unit will behave.

look at it this way given a theoretical ratio of 100%, then assume an increase in the tow vehicles weight [as ready for the off]. of 15% then also assume the trailer is not loaded up to it's MAM, but is 10% lighter. the practical ratio under tow would be more like, 75%.

 

[ProfJohnL]

Lets put the question in a slightly different way

At what tow ratio does the caravan dictated the tow vehicles behaviour?

 

[colin-yorkshire]

Lets put the question in a slightly different way

At what tow ratio does the caravan dictated the tow vehicles behaviour?

no idea Prof, although I did use to tow a 1200kg caravan with a 1125kg car [theoretical values] with no ill effects.
in fact it was one of the best combinations I have used by far. did thousands of miles with that unit.