Does the actual noseweight of an outfit make any difference to the way a 'van tows? The recommended noseweight for both our car and van is 75Kg. Am I better to tow with that noseweight, or should I aim to get it significantly lower? Will it make a difference to how the outfit handles? Given that Baileys are making a big deal of their efforts to reduce the noseweight in the new Unicorn series, is that the way to go. Over the many miles we have towed, we tend to have had the noseweight around 5 - 10 kg below the limit and never had any problems. It would be nice to get some definitive advice on this, once and for all.
Noseweight and towing
- Thread starter glegin
- Start date
Not sure you will get anything 'definitive' but noseweight does affect towing stability.
Years ago there was a rule of thumb, generally quoted with the 85% "rule" that suggested noseweight of 5 to 7 % of caravan max weight (as it was known then) subject to not exceeding the stayed caravan and car limits.
I am a little surprised that your van has a 75kg limit as most hitches are around 100kg, but the car figure is, unfortunately, about average.
Years ago there was a rule of thumb, generally quoted with the 85% "rule" that suggested noseweight of 5 to 7 % of caravan max weight (as it was known then) subject to not exceeding the stayed caravan and car limits.
I am a little surprised that your van has a 75kg limit as most hitches are around 100kg, but the car figure is, unfortunately, about average.
glegin said:
The short and simple answer is yes noseweight does affect the way a caravan will tow. As you find you are having no problems running with 5 - 10 kg below your 75Kg limit, then there is no need or reason to increase it.
As Ray states, there is no definitive value answer, each time you tow you will load the caravan slightly differently and encounter different road conditions which will affect the way the caravan tows so there is no fixed nose load value that is right. Generally greater nose load is better than less, providing you do not exceed the limits set by the manufacturers. Exceeding nose load limits is illegal, and dangerous.
If you have insufficient nose load the outfit will begin to feel twitchy and unstable. Stop and add more nose load. or run at a lower speed until you can correct the problem.
Yes, definitely - the greater the noseweight the more stable the tow - BUT - you/I must never exceed any of the limits imposed on noseweight, ie car, towbar, towball, hitch or A-frame.glegin said:
Whether anyone can detect the effect of small differences is immaterial.
The general guidance is to run the noseweight as high as possible consistent with not exceeding the hitch maximum. For example our Passat Estate has a specified hitch maximum of 90Kg, but the Thule bar fitted with a removable ball is rated 85Kg, so 85Kg it is. Doesn't matter if it is a few Kg lighter, but if it is heavier and your hitch failed you would have a hard time explaining to the insurance company let alone the police or court if it came to that.
The problem is that so many new vans are now up there when empty. The Mk1 Unicorn (2 berth - can't remember the model) was 88Kg on the ball ex factory! When you put a 6Kg bottle in the locker you are starting to get into dangerous territory. The only solution is to put load in the (rear) bathroom to counterbalance but then you risk tail-wag which can be frightening. I note that in the Mk2 they have done a new layout for the kitchen to accommodate the gas locker beneath it and more importantly behind the wheels to reduce the noseweight.
One final point often overlooked if you are lucky enough to use such as a Disco for towing: the hitch maximum for an Al-Ko chassis is 100Kg!
The problem is that so many new vans are now up there when empty. The Mk1 Unicorn (2 berth - can't remember the model) was 88Kg on the ball ex factory! When you put a 6Kg bottle in the locker you are starting to get into dangerous territory. The only solution is to put load in the (rear) bathroom to counterbalance but then you risk tail-wag which can be frightening. I note that in the Mk2 they have done a new layout for the kitchen to accommodate the gas locker beneath it and more importantly behind the wheels to reduce the noseweight.
One final point often overlooked if you are lucky enough to use such as a Disco for towing: the hitch maximum for an Al-Ko chassis is 100Kg!
Woody3 said:
Hello Woody,
I think you are overstating the problem. Yes some caravans do have high ex works nose weights, but very few of us actually tow caravans in their ex works state. It is almost certain that some loading of heavy goods will be required to off set high nose loads, but in reality if you had a nose load of 100Kg and you needed to get it down to 75 that only means adding about 30Kg to the rear of the caravan, and if that is enough to cause significant instability then you should be looking for other reasons for the caravan to be so sensitive.
Low noseweights in Europe is a historical/cultural thing - otherwise identical cars sold in Australia have similar towing limits to Europe but much higher maximum noseweights - in North America, otherwise identical cars have similar maximum tongue-weights to the Australians but about half the towing limit used in Europe and Australia.
Mind you, North America still uses oil change intervals (OCI) much lower than Europe - typically 3,000 miles, maybe 5,000 using synthetic oil - Europe seems comfortable with 20,000 mile OCI using synthetic.
The "problem" with cars internationally is that each country's local marketing company can/do over-rule the engineers who built/tested the cars.
So, stick with "noseweight as heavy as possible without exceeding ANY limit" and don't lose any sleep trying to second-guess the engineers.
Mind you, North America still uses oil change intervals (OCI) much lower than Europe - typically 3,000 miles, maybe 5,000 using synthetic oil - Europe seems comfortable with 20,000 mile OCI using synthetic.
The "problem" with cars internationally is that each country's local marketing company can/do over-rule the engineers who built/tested the cars.
So, stick with "noseweight as heavy as possible without exceeding ANY limit" and don't lose any sleep trying to second-guess the engineers.
Just to make things more complicated ! - no one has mentioned that nose weight changes,the nose weight when towing is less than the static nose weight.Don't ask me what the difference is because I don't know.
Hello Bertieboy,
Your statement is only partly true. The fact is the actual nose weight on the hitch when the outfit is in motion is constantly changing, as the car and caravan goes over bumps and dips. The degree of change depends on how quickly the tow ball goes up and down. Some testing I was involved with at MIRA some years ago demonstrated the vertical load on the tow ball can be changed both positively and negatively by up to +/-5x the static nose load, but this is constantly changing and is more of a vibration that a long shove.
The other main factor which I think you are probably thinking of, is the aerodynamic load created by the wind striking the front of the caravan
and which you can easily imagine tries to push the top of the caravan backwards lifting and unloading the hitch. Unfortunately it is difficult to generalise about this aerodynamic effect as each car and caravan design produces different effects.
Some of the modern caravans have quite smooth front edges, and in fact in some cases the deflection of the airflow over the front of the caravan could push the nose down - increasing the actual nose weight
But that isn't the only effect of windage you need to consider, you must also consider the airflow over the roof and under the caravan both of which will produce areas of lift and down force. Where they occur will affect the nose weight but in some cases the net effect may be negative or it could be positive. and the scale of the effect may only be net change of a few Kg rather than 10's of Kg.
Car manufacturers will be well aware of these dynamic changes and will factor in appropriate safety margins in the design of the tow bar arrangements, just because the towbar can handle larger dynamic loads does not mean you can overload the static limits when towing.
Your statement is only partly true. The fact is the actual nose weight on the hitch when the outfit is in motion is constantly changing, as the car and caravan goes over bumps and dips. The degree of change depends on how quickly the tow ball goes up and down. Some testing I was involved with at MIRA some years ago demonstrated the vertical load on the tow ball can be changed both positively and negatively by up to +/-5x the static nose load, but this is constantly changing and is more of a vibration that a long shove.
The other main factor which I think you are probably thinking of, is the aerodynamic load created by the wind striking the front of the caravan
and which you can easily imagine tries to push the top of the caravan backwards lifting and unloading the hitch. Unfortunately it is difficult to generalise about this aerodynamic effect as each car and caravan design produces different effects.
Some of the modern caravans have quite smooth front edges, and in fact in some cases the deflection of the airflow over the front of the caravan could push the nose down - increasing the actual nose weight
But that isn't the only effect of windage you need to consider, you must also consider the airflow over the roof and under the caravan both of which will produce areas of lift and down force. Where they occur will affect the nose weight but in some cases the net effect may be negative or it could be positive. and the scale of the effect may only be net change of a few Kg rather than 10's of Kg.
Car manufacturers will be well aware of these dynamic changes and will factor in appropriate safety margins in the design of the tow bar arrangements, just because the towbar can handle larger dynamic loads does not mean you can overload the static limits when towing.
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