Payloads

[Keith T]

On another posting, reference is made to the fact that testers use the manaufacturers quoted payloads in the 'statistics' box. Surely it's not beyond the bound of possibility, or even the ability of the testers, to have the vehicle weighed either totally unladen, and the usual caveat of allowance added, or alternatively add that weight before weighing?

 

I am amazed even using some of the quoted figures how little payload there is especially on some of the 'family' vehicles. Do people really buy motorhomes which even the manufacturers suggest has a payload of around 300kg!

 

I also notice more and more new motorhomes being advertised as based on the new Fiat 'Maxi' chassis (or similar) of 4tons.......no one however sems to raise the issues and implications of going above the 3.5t figure. As far as I am aware, this especially affects speed limits and just where you can take the vehicle (ie max 3.5ton signs), as well as the driving licence problem as we get older. This is something which I feel should be highlighted both in advertising and editorial/reviews. - and also by dealers There may also be other restirctions of which I am not aware, but for me the sensible max is 3.5t, and is it simply a question of wanting more and more inside which seems to have made motorhomes heavier?

[JohnP]

It's not just getting older. A young person with certain types of diabetes will have to notify the DVLA who may restrict them to a maximum of 3.5 tons.

[colin]

Seems the one to look out for is 'essential habitation equipment' this has to be taken into account also.

Should the mags police manufacturers? Do manufacturers lie about weights? If you can't trust them to tell truth about weights can you trust them to build a van?

 

[Keith T]

colin - 2008-02-24 8:38 PM

 

Seems the one to look out for is 'essential habitation equipment' this has to be taken into account also.

Should the mags police manufacturers? Do manufacturers lie about weights? If you can't trust them to tell truth about weights can you trust them to build a van?

 

I think there seems more 'standardisation' now on the 'essential' itms, and it's relatively easy to work out I guess.

 

No I don't think the mags should 'police' the industry, and where they list the models, then manufacturers figures are fine. It is to a degree up to the purchaser to check that it is adequate for the purpose.

 

However, when reveiwing, I do think they have a duty to reveiw all elements, and to my thinking that should include measurements and weights.

 

With many current models not supplying a spare wheel as standard, they would also be wise to state whether or not one is supplied, especially as there is consdierable weight if one of these together with cradle has to be added to the basic (before payload) weight.

[Guest Tracker]

colin - 2008-02-24 8:38 PM

 

Q. Seems the one to look out for is 'essential habitation equipment' this has to be taken into account also.

 

A. YES - ensure that the stated payload is in addition to the above and not inclusive.

 

Q. Should the mags police manufacturers?

 

A. Why not? No one else does?

 

Q. Do manufacturers lie about weights?

 

A. Some of them are perhaps economical with the truth sometimes?

 

Q. If you can't trust them to tell truth about weights can you trust them to build a van?

 

A. In some cases, yes and in other cases, NO!

The trick is to trust no one and carry out your own checks - and don't buy a van with a small stated payload unless you travel very light!

 

 

 

Not everyone is out to get us, although it may seem like it at times!

 

Sometimes mistakes happen through ignorance or over enthusiasm to get the sale - so really just one very important maxim - CAVEAT EMPTOR!

[colin]

Looking at Twin with 120jtd, starts out at user payload 530kg, less est.hab.146kg,towbar 45kg,comfort pack 29kg,sparewheel 25kg, passenger 60kg, suddenly we're down to 225kg of payload, doesn't sound quite as good, especialy if we add in a couple of passengers and their tent.

[Minstrel]

What exactly is essential habitation equipment?

 

[Guest JudgeMental]

 

as a diabetic restricted to 3500KG and also having a family, payload was a critical factor last year when I purchased a new EuraMobil motorhome.

 

German magazines seem to have no trouble weighing their test vehicles and in fact tend to weigh each wheel as well - makes you wonder don't it *-)

[colin]

Minstrel - 2008-02-24 11:45 PM

 

What exactly is essential habitation equipment?

I believe thats gas and water

[bigal55]

passenger 60kg? don,t take me :D

[Keith T]

Minstrel - 2008-02-24 11:45 PM

 

What exactly is essential habitation equipment?

 

I think it depends on th manufacturer - my last 2 motorhomes according to the brochure include driver (all 75kg), 90% fuel and fresh water, (no waste water), cables and 13kg gas again 90% I think.....but others are not so generous!

[Keith T]

Minstrel - 2008-02-24 11:45 PM

 

What exactly is essential habitation equipment?

 

I think it depends on th manufacturer - my last 2 motorhomes according to the brochure include driver (all 75kg), 90% fuel and fresh water, (no waste water), cables and 13kg gas again 90% I think.....but others are not so generous!

[Derek Uzzell]

(This is a variant of my article originally published in “Caravan, Motorhome & Camping Mart”, October 2003. It's getting a bit long in the tooth now, but it still might be useful.

 

The guidelines apply to all motorhomes, but will be of particular importance if you are looking for a ‘family’ ‘van. Beware of designs offering lots of seats and/or berths at a bargain price as the vehicle may well be constructed on a light payload chassis. Also be careful if buying abroad or purchasing a LHD import. The maximum weight of Continental European motorhomes (particularly French ones) is often deliberately restricted to 3500kg to meet home market requirements and can result in a very limited useful payload.)

 

 

PAYLOAD CALCULATIONS

 

Thinking about a new motorcaravan?

 

We all recognise that our motorhome should have enough load capacity. We also know that calculating payload is easy – refer to manufacturer’s brochure, note vehicle’s maximum permitted weight, subtract ‘empty’ weight and the result’s the payload. Well friends, the first statement’s true, but, for the second, as they say up North, “Think on!”

 

Motorhome constructors don’t standardise on language. So brochure-terms used to describe a ‘van’s basic weight may be “ex-works”, “unladen mass”, “roadside weight”, “mass in running order”, etc. And, whatever the wording, this figure may, or may, not include certain crucial weight factors.

 

Let’s choose “Mass in Running Order” (MRO) for a motorhome’s empty weight. Constructors use two significantly different ways to define MRO. Formula A involves the weight of the vehicle in ready-to-drive condition, plus the weight of a driver and fuel. Formula B includes the vehicle, driver and fuel weights, plus a further allowance for “essential habitation equipment”, which actually means on-board fresh water and gas storage.

 

The ‘driver weight allowance’ is usually 75kg (close to 12 stone), while the ‘fuel weight allowance’ may relate to a fuel tank either 90% or 100% full. Fresh water and gas allowances are usually 100% or 90% of the maximum weight of the motorhome’s water-tank contents and 100% or 90% of the weight of full gas-bottles. But the most frustrating thing for the motorhome purchaser is when the beggars don’t explain their sums.

 

Some advertising brochures will inform you whether the quoted MRO involves Formula A or B, while others tell you sweet nothing. It’s a fair bet that all motorhome builders include driver and fuel allowances in their MRO and an equally good bet that, if water/gas allowances aren’t mentioned, then they aren’t included. If there’s any doubt over an MRO figure, the wise thing to do is to seek advice from the motorhome constructor (not the dealer or salesman!). As a VERY general rule, UK manufacturers have tended to use Formula A, while European converters prefer Formula B.

 

OK, you’ve confirmed how the MRO is made up for the motorhome at the head of your shopping-list - now you must decide whether the payload will be adequate.

 

Firstly, if the manufacturer has used Formula A (vehicle + driver + fuel), then you need to add water and gas weights (and that should mean as much water and gas as the ‘van will accept). Water weighs 1kg per litre, a full 6kg (propane) gas-bottle about 14kg and a 13kg bottle about 29kg.

 

If Formula B has been employed then water and gas weights are already included in the MRO, but if these are 90% weights then add in the missing 10%.

 

Now subtract the motorhome weight inclusive of vehicle, driver, fuel, water and gas from the ‘van’s maximum permitted weight. What’s left has to cover all accessories, baggage, passengers, pets, etc. that will accompany you on your travels. Let’s call this figure “Remaining Payload” (RP).

 

Next, subtract from the RP the weights of any ‘must have’ vehicle options, conversion options and accessories (eg. cab air-conditioning, auto-gearbox, tow-bar, bike-rack, awning). There is a ‘Euro Norm’ (EN 1646-2) that defines how motorhome weights/payloads should be expressed and we’ll follow its guidelines. So now subtract 10kg per metre length of the motorhome. This is on the basis of “the longer the motorhome the more storage: the more storage the more junk you’ll carry!”

 

EN 1646-2 says that a ‘standard passenger’ weighs 75kg and has a minimum of 10kg of personal baggage. So now subtract 10kg from the RP for the driver’s baggage. What remains of the RP has to cope with all other passengers + their baggage at 85kg each (75kg + 10kg).

 

Take away 85 from what is left of the RP – that’s 1 passenger you can carry – and continue doing this until the RP is less than 85. The number of subtractions you have made represents how many passengers the motorhome can transport without going overweight. You can now match up the number of ‘portable’ passengers with the number of travelling positions in the motorhome. (This is where things may get interesting.)

 

Let’s consider the popular Hymer C544K coachbuilt motorhome. In entry-level form this has a maximum permitted weight of 3000kg. Its MRO is 2790kg and, as Hymer use Formula B (100% version), this includes a 120kg allowance for fresh water (120 litre water tank) and 50kg for gas (2 x 11kg German bottles). That leaves an RP of 210kg (3000-2790). To make things simple, we won’t specify any vehicle/conversion options or accessories.

 

A C544K’s length is 5.61 metres, so we’ll next subtract 55kg (10kg x 5.5 – let’s keep on keeping it simple!), plus 10kg more for the driver’s baggage. That’s 210kg-65kg, leaving 145kg for passenger carrying. 145kg minus 85kg leaves 60kg. So you can carry one ‘standard passenger’ (in addition to the driver) and have 60kg of payload remaining. However, what may give you pause for thought is that a Hymer C544K has a 4-person dinette and could carry six people overall in front- or rear-facing travel seats.

 

Before anyone goes rabid about Hymer marketing potentially illegal motorhomes, it must be emphasised that the above figures were derived from Hymer’s brochure where “maximum permitted passengers” for the basic C544K is stated as two (driver + 1). If you reckon the payload of the base-model won’t be enough for your needs, or you want to carry more passengers, there is a chassis upgrade to 3200kg raising passenger capacity to four (driver + 3). There are also 2 versions of this motorhome with alternative motor/chassis combinations that (based on the above calculations) would allow 6 people to travel and still leave some payload spare.

 

(In fact, of all manufacturers’ brochures, Hymer’s is arguably the most informative for payload details. If you buy a Hymer and subsequently find the payload’s insufficient, it really will be your own fault.)

 

Some readers will now be saying, “But we are a family of 2 skinny adults and 2 tiny children, so this 75kg ‘standard passenger’ thing doesn’t apply”. Or, “But we will never run the ‘van with a full water-tank”. Well, that’s fine – this is not a Delia Smith recipe where everything is exact, so you can fudge the figures to your hearts’ content. But, if you discover you are massaging the numbers to keep within your favourite ‘van’s maximum weight limit, you really should ask yourselves whether that particular motorhome design is right for you.

 

Anxious enquiries or unhappy tales about motorcaravan-payload appear regularly in leisure magazines. As everybody’s motorhome requirements differ, it’s down to you, the prospective owner, to decide how much ‘spare’ payload you need to make you feel comfortable, or how little you are prepared to tolerate. The important thing, surely, is that some elementary maths will help you make an informed decision.

[Roamer]

Hi All

 

A very comprehensive post, Derek, but one item that I always take into account, due to being caught out once, is the 5% tolerance allowance in the manufacturers figures. Remember this includes the values supplied for added extras.

 

Taking your example, the Hymer C544K coachbuilt motorhome with a MRO is 2790kg would have an unladen weight (taking off the fixed mass objects, driver fuel etc) of approx 2400 Kg. This gives an actual 5% tolerance of 120Kg.

 

The “Remaining Payload” (RP) in the worst case situation, but still within manufacturing tolerance, is only 90Kg ( 210 kg [RP from derek's post]- 120kg [tolerance]) and it this figure that I would use, which just about allows for a passenger and very little else.

 

I know I have added this to a number of previous threads but it is very important, as in the above example, any purchaser of a vehicle that had the worst case situation could not rejected it based on its poor payload.

 

Looking on the brightside, most vehicles will not be at this end of the scale, which means that after using a weighbridge you find you have additional payload to cope with those unexpected purchases when on route.

 

 

 

[Tomo3090]

Definition of "essential habitation equipment" as follows:

 

Hairdryer, curlers, hand mirror, make up, minumum of 8 pairs of shoes, warm weather clothes, cold weather clothes, wet weather coat(s), various lotions, potions and powders not included in the definition of "make up", assorted brushes and combs, books, clothes in case we "go anywhere nice", Chennay wine X4, Martini (Rosso and Bianco), chocolate and the dog!

 

This is a list of essential stuff, the optional equipment is longer!

[Guest JudgeMental]

 

an international flight allows approx 32 kg per person, so how on earth do they come up with 10 kg *-)

 

what about pots and pans, beach stuff, outdoors stuff etc.....

 

I posted extensively on this before and after buying my new van last year. and it is possible for 4 to travel and just about stay legal @ 3500kg.

 

personally if purchasing a van you were unsure about I would make a weight slip a condition of purchase. EuraMobil are a reputable manufacturer and I found published weights were correct when I visited weighbridge. I also visited again fully loaded with family before trip just to make sure.

 

 

[Mel E]

Just to add a little complication:

 

You may not actually be able to use up the full MAM (3500Kgs, say) in practice, so your payload may be smaller than it would appear.

 

Why not? Because, as well as staying within the MAM (Max Authorised Mass) you must also stay within the max load on each axle. Any large weight near the rear will add 160% to 180% of its weight to the rear axle because of leverage.

 

This only becomes a potential problem once you get close to the limit of MAM. There is normally adequate latitude (the sum of the two axle weights exceeds the MAM by a reasonable amount), but this may not be the case and is well worth checking. It's often a very real problem with motorhomes that have been up-plated to a higher chassis weight.

 

Mel E

====

[Brian Kirby]

It gets worse, because the converters do not all make clear that different versions of the base vehicle chassis/engines have different weights.  As a generalisation, the figures quoted to arrive at payloads will be for the base chassis version with the smallest engine offered, without reference to any of the chassis manufacturer's options that may be offered, i.e. cab air-con, ABS, airbags, larger engines, different gearboxes and so on.  Generally, the German made vans are quite good with these, but you have to get the technical supplement to the glossy brochure to find out how much these chassis options weigh.  Even uprating the rear axle by 100Kg can add 10Kg to the weight of the vehicle, so that the net gain to payload falls to 90Kg.

The dealers should know all this, but my general impression is that they don't, or can't be bothered to find out.  Almost any van with an MTPLM of 3,500Kg should be regarded as a vehicle with payload limitations, and should be approached with great caution.  As Mel points out, to all this must be added the individual axle loading limitations. 

I hope he'll forgive me for revealing this, but Mel has a rather snazzy spreadsheet which calculates how your added load affects individual axle loadings.  In the past he has offered to pass on copies, and I have one that I have adapted.  If you want a blank of my adaptation I'll be happy to e-mail you a copy, or if you want the "authorised version", maybe Mel still has his available.  Mine is in Excel, so I don't think it will work in Microsoft Works. 

However, it isn't a panacea.  You have to individually weigh every bit of kit you take, including driver and all passengers, you have to measure wheelbase and rear overhang, plus the positions of all your seats/cupboards/lockers relative to the rear axle centre line, and you must first get the individual axle weights of your van at a weighbridge - ideally in its unladen state i.e. with no water, no gas bottles, no waste, and all cupboards and lockers empty. 

You then decide where the kit goes, add it to the spreadsheet, and the spreadsheet tells you what effect this is having on your axle loads.  It also allows you to play with, for example, the effect of driving around with the waste tank full rather than empty, or leaving the bikes at home, or whatever.  You'll need a bit of familiarity with Excel though, as there are a number of linked worksheets, and a few moderately advanced formulae.  If you're into macros, you'll eat it, but I'm not, so it doesn't go that far!  PM me with your e-mail address if interested.

[RonB]

As I mentioned elsewhere, if a converter chooses not to comply with the standard EN1646-2 formula you should ask yourself, and them, why? In most cases you can bet your bottom doller that if they did their final payload figure, listed or brochured, would come out less than they are claiming.

 

The payload situation is a farce and I feel for the newcomers to our hobby who cannot really on much of the published info.