Nose Weight - question for Lutz.

[S_374382905]

I have a problem with nose-weights too, and would be grateful if Lutz or others could advise. The problem is as follows:

1. My car has a maximum noseweight of 80Kg - I know I cannot exceed that (in spite of what some caravan dealers have told me!)

2. The caravan I am wanting to change to has a noseweight (unladen) of 78kg. That is, even before I put anything into the caravan it weighs 78kg at the hitch.

Does this effectively mean that I will never be able to keep the noseweight under 80Kg, irrespective of how I load the caravan? To me, it appears that even a couple of thick books placed anywhere near the front of the caravan will take me over the cars noseweight limit.

Grateful for any comments

 

[Lutz]

No, it just means that you must make sure that the net result of all the payload ahead of the axle and that behind the axle must balance out, rather like an old set of weighing scales. Keeping a balance will ensure that the centre of gravity moves neither forward nor to the rear and the noseweight remains unchanged.

 

[S_374382905]

Lutz

Thanks for your prompt response. I understand the principle of what you are saying, but with such a tight margin, am I likely to realistically achieve it?

For example - two gas bottles (at around 12Kg) in the front will surely present at a similar weight at the hitch - thereby 'taking me over'. Or, do I simply counterbalance this with more items further back?

Sory to sound dense, but this has definitely been a confusing subject for me, and as I am about to close on the deal for the new caravan at the weekend I dont want to find that I am having to fill the car up with everything before I leave.

I guess the simplest way of putting it is "is it practically possible (with careful loading)to ensure that the ex works nose weight (in this case 78Kg) remains at that when I load the caravan with all the gas bottles etc - provided of course I am sensible and check the weights.

Thanks for your patience on this.

 

[ProfJohnL]

Hello S,

The unloaded caravan is a very unnatural condition, and the nose load produced when the caravan is empty is not necessarily the best target weight when the caravan is in its loaded condition.

In fact the nose load only needs to be enough to maintain a stable outfit, so aiming for a lower value is quite permissible, but you have to suck it and see.

It should be perfectly possible to keep the nose weight within limits. As Lutz said its just like a balance scale or see-saw, with the effective pivot being the main axle.

If the nose is too heavy, then move a heavy item that is front of the axle to a position behind the axle. This will reduce the nose force. However do not be tempted to store a gas bottle in any other place than its proper loction in the front locker of the caravan.

A few tips though, Only keep the gas bottles in the front locker, avoid adding the little extras like chocks steadies handle keep them elsewhere. If absolutely necessary only take one gas bottle, or opt for the light weight versions

 

[JTQ]

Its unladen nose weight is not in itself a figure of any importance; the only figure that matters is the laden nose weight.

If the caravan designer [as opposed to the stylist!!!] has done his job properly then a normally laden van will have a nose weight within the chassis and hitches rating. Unfortunately in the past the stylist have on occasion ruled the day, even if there was a designer employed!

The upper limit for most Al-Ko based UK built vans is 100kg.

As you're aware you cant in your case go above 80 kg.

Whether the van you have in mind can be sensibly loaded to get that is something nobody here can tell you unless you quote the model and a contributor has specific knowledge of living with that van.

Hopefully getting to 80kg when loaded is not out of the question even though it might be at that figure without anything in it.

If nobody can confidently help you and even if they can then I would make achieving the 80kg laden a contractual condition and take all the clobber to the dealers and test it; we did a similar sort of thing as weights were critical.

 

[xtrailman]

s

you have little choice but to load heavy items low down and behind the axle, move them further back as required until you achieve the desired nose weight. Remove as much you can from the front locker, i carry only one light weight gas bottle, which weighs 10kg when full.

ensure the ballast is securely held in place, if the load moves your nose weight will obviously be all at sea.

What van is it? If you have the mondeo, the latest version has a 90kg nose limit, so i understand.

 

[Gafferbill]

There is a mine of information in Features on this website.......

Noseweight......

http://www.practicalcaravan.com/features/noseweight.html

 

[S_374382905]

Thanks to all for your replies. I will make my purchasing decision this weekend, but having looked at some depth at the issue of noseweight I do remain slightly concerned.

Put simply, the vast majority of caravans I have looked at all have an ex works nose weight which exceeds the cars limit of 80Kg. In other words, they are already too heavy at the hitch to be legal. Having looked at many saloon cars towing caravans like the ones I have been looking at I wonder how many realise they are possibly invalidating their insurance and warranties?

No amount of 'backloading' will reduce the ex works nose weight of a caravan as safely as it ought to be, and the situation when towing the van empty e.g to and from a service or upon delivery.

In my case, I think I will wait unti the time comes to change my car and then choose one which will tow the caravan of choice at that time - ie the nose weight of the car in particular, bot especially the 85% rule, which I have no real concerns about.

Thanks again to all for your contributions though.

 

[ProfJohnL]

Hello S

You are right to be concerned at 'back loading' and getting the nose weight right.

But at the risk of being accuse of repeating my self, you should not pay any great attention to the ex-works nose weight. It bears no relation to the finished nose weight of a loaded caravan.

As soon as you add any item to a caravan the nose weight will change. the trick is to load your items, then check the nose weight. You might be surprised and find its fine, but even if it isn't it may not need as much movement of items to bring it into range. Don't forget that if you remove 10Kg from the nose and put it at the back, the overall weight has not gone up, but the nose weight will reduce by more than 10Kg. If an outfit becomes unstable because of only a 10Kg mass change, then in my book the outfit is too close to being unstable anyway.

But for reassurance on this, look at the number of caravans that have been trimmed to get the right nose weight who experience no problems!

You must of course make your own mind up about this, but I do think you are perhaps being unnecessary cautious about this point.

 

[ProfJohnL]

Thanks to all for your replies. I will make my purchasing decision this weekend, but having looked at some depth at the issue of noseweight I do remain slightly concerned.

Put simply, the vast majority of caravans I have looked at all have an ex works nose weight which exceeds the cars limit of 80Kg. In other words, they are already too heavy at the hitch to be legal. Having looked at many saloon cars towing caravans like the ones I have been looking at I wonder how many realise they are possibly invalidating their insurance and warranties?

No amount of 'backloading' will reduce the ex works nose weight of a caravan as safely as it ought to be, and the situation when towing the van empty e.g to and from a service or upon delivery.

In my case, I think I will wait unti the time comes to change my car and then choose one which will tow the caravan of choice at that time - ie the nose weight of the car in particular, bot especially the 85% rule, which I have no real concerns about.

Thanks again to all for your contributions though.

85% is not a rule. It has no magic ability to ensure a good tow, some outfits can be bad at less than 85%, and others can be quite satisfactory up 100%.

85% is only guideline, Good towing is down to keeping a range of criteria under control, weight ratios are only one and in my book speed and the driving habits of the driver are probably more influential on stability than the weight ratio.

but it does make sense to keep a trailer as light as possible compared to the tow vehicle

 

[Glenn_5132962]

While its possible to balance the outfit by careful loading it'll probably been a right pain. Unless its a fixed bed model most vans have much more storage in front of the axle than behind. This being the case do you really want all the bits & bobs such as leccy cable, aquaroll, wastemaster, chocks etc loose at the back of the van?

The heaviest items you will carry are probably battery, gas bottle & food. If the battery box & fridge are both fwd of the axle it'll be hard work to maintain noseweight limits without having putting things against the back wall & this is bad as it increases the moment of inertia (dumbell effect).

BTW how do you know what the empty noseweight is? I've not seen this data published. If you measured it yourself did you put the scales under the hitch or under the jockey wheel? If you measured the wheel you would get a false (high) reading.

 

[S_374382905]

Glenn

To obtain the 'ex works' noseweight I rang the caravan manufacturer - you are right, they do not normally publish this figure.

I think I may have caused some confusion in relation to the nose weight issue by the way I framed my questions too.

My concern isnt about 'trimming' the noseweight to get it down to the maximum allowed for the car, rather it was about the 'starting point'to achieve this.

What I have found is that many caravans already weigh (at the nose)far more than the car is allowed to have on the tow bar, when they leave the factory. Therefore, it is not possible to reduce this without moving stuff to towards the back. This may or may not be achievable - but the main issue is (for me)that when I collect the van (from new)or when I take it for a service etc, I will be faced with having to unecessarily pack it with things just to keep it legal and safe, which I really dont fancy doing.

My current van has an 'unladen' noseweight' below the cars maximum, and I can easily maintain this by loading it correctly. I can also tow it empty of everything and still be legal and safe.

Also, I know that the 85% rule is just a guide. I am not at all concerned about this, and have enough experience and common sense to make a judgement on how far to exceed this. My personal prefernce is to keep as close to it as possible - if for no other reason than the cars performance/fuel economy etc.

Everyone has been really helpful as ever on this topic, but as I say, the way I framed my questions might have caused some confusion. Personally, I dont think anyone can be too careful about nose weights, which is why I raised the issue. Trimming the weight by loading is 'standard caravanning practice, but I really do wonder how many people are buying caravans without realising the nose weight of the caravan is already heavier than their cars are allowed to take before they put so much as a single item in them?

 

[Gafferbill]

...... by definition you are measuring and adjusting the noseweight when the vehicle is stationary.

In practice, pitching causes shock loads which can cause noseweight to vary widely.

 

[xtrailman]

s

I think as you that the ex works nose weight so be made known, when i bought our Avondale in 1976 all the nose weights were declared, ours a 2 berth end kitchen was 35kg. So from this we actually took ballast and loaded up the bottle box, this got us to the 65kg that our car was happy with.

However i remember when we bought our bailey in 2004, no one could tell us the nose weight!

I find this quite incredible, so we took our nose gauge to check, along with some ballast. I cant remember the nose weight but on this occasion the nose weight was ok .

But yes as you say there are occasions when the van has to be towed unladen.

 

[Royston]

I have read with great interest , the information given freely that to attain the correct noseweight load the heavy items behind the axle, this is a very dangerious thing to do, why do you not think that all the caravan manufactures place all the heavest items in front of the axle, to place any heavy item behind the axle can cause the caravan to have a pendalum effect , where the slightest twitch of the stearing wheel can encourage a snake to occur.

It has been mentioned that Baileys do no provide a nose weight, all the baileys that I have purchased, within their very extensive manuals provided , the maximum static nose weight for all baileys is 100Kg, should never be exceeded,The nose weight should be approx 7% of the actual laden weight(i.e.between 50 and 100 Kg.

My nose weight is governed by the towball , with all my vans I have managed to keep within the towball limits without the need to counter balance the van , also tow with a 92% never had any problems.

This area of trying to achieve the correct noseweight by fair means or fowl , really needs looking into, legislation of some form to clarify this very grey area .

To improve safety, why cannot the nearside axles on all vans have

left hand threds on the studs ,My gas cylinders has them so why cant they be fitted , This is becoming a major problem with alum wheels where despite the nuts being correctly torqued they are still becoming loose.

Royston

 

[Lutz]

The 7% formula can be safely ignored despite it being recommended by various sources as there has never been any substaniated evidence that it is actually the optimum. It is normally much better to just stick to a noseweight which is just less than the lower of the two limits specified for car and caravan, respectively.

As for never placing loads behind the rear axle, some 2010 Adria models have two interconnected onboard water tanks, one at the front and another at the rear, with the express object of using water as ballast to adjust the noseweight.

 

[Royston]

Using water as a ballast is even worse , water is the most unstable thing to have swishing around inside the rear of a touring caravan when the van is on the move, I always empty my heater which is positioned at the rear offside of the van.

With motor homes it is a much lesser problem.

Royston

 

[ProfJohnL]

Hello Royston

I think you may be misreading the situation. Yes manufactures do locate most of the appliances in front of the axle, and that might be to create a positive nose load, but that does not mean you shouldn't load heavy items behind the axle. You just have to be sensible about it. In actual fact, even heavy items in front of the axle will provide the inertia that can perpetuate the pendulum effect, BUT, provided the caravan has been loaded sensibly there will still be a significant load margin before an uncontrolled pendulum effect ensues.

I am not sure where you get your limits of 50to 100Kg from. The towing regulations set the minimum value of the nose to be 4% of trailer MTPLM a minimum limit of 25kg. The upper limit is determined by the lowest mechanical specifications of the tow vehicle and the trailer hitches.

That is in essence the legislation.

I don't see any realistic method of tightening it up, without it compromising the safety of some outfits. We regularly see on this and other forums contributions that show there is a wide variety of nose loads in use, so a one size fits all is just not going to work.

 

[Royston]

Hi John,

The limits quoted form part of Baileys Manual instructions,which I have always abided by and hence have had trouble free towing.

Royston

 

[xtrailman]

royston

The 100kg nose weight quoted in the bailey handbook, refers to the MAX nose weight for the ALKO chassis.

The recent posts were discussing UNLADEN nose weight, ex works.

While ballast behind the axle is not ideal, if securely fitted and low down, then it is perfectly acceptable, my end wash room already has ballast fitted in the form of two wardrobes, a sink unit, a fitted shower, shelves, ducted air, plus a toilet.

You are correct re your comment about carrying water in the onboard water tank, but that is only because the bailey onboard water tank, is not designed or fitted to cope with 40 litres of water, that is not to assume that applies to OTHER makes.

 

[Lutz]

I haven't had a close look at the 2010 Adria models in question, but I presume that if they have two water tanks then neither of them will carry more than 20kg and 20kg is not going to have a significant effect on stability. Maybe they even have internal baffles, which would make the situation even less critical.

 

[JTQ]

Lutz wrote:

"Maybe they even have internal baffles, which would make the situation even less critical."

It's even possible with the correct design of the "water tank system" for it to be a distinct advantage in damping the natural frequency snaking motion!!

Akin to the "Flume tank stabilisation systems" for boats and ships?