Struggle to put N/Weight ON!

[Gagakev]

Just been checking nose weight and am struggling to get to around 85-90kg but it's the other way round, I'm too light on the front and am around the 70-75kg mark!
In front locker; I have two full 7kg propane gas bottles, spare wheel, wooden chocs, awning pegs, EHU cable, mallet, steel hammer,
picnic table, etc etc.
The battery is near front, mover on front side of wheels, clothes in lockers at front, lockers in rear empty.
under bed storage at rear has 2 ali fold up chairs, ali washing line, 1 wind break.
I've even got water in the heater near the front!!!!
Is this right for newer vans? It is an 8.0m (includes A Frame) single axle.
Any suggestion's or shall I get a few cates of beer!!!!

 

[ProfJohnL]

Hello Kev,

Teh nose weight only needs to be bigenough to minimise or delay the onset of instability. What that figure should be no one can tell you as its unique to each outfit.

However teh EU does set out minimum nose weight values : It must be a minimum of 4% of the MTPLM, or 25kg, which ever is greater, and of coures it mut not exceede either the cars tow ball vertical load limit or the traier s hitch limit.

The general concensus is you should aim to set the nose load towards the top of then available window of limits, from my experience, most caravans tow adequately with nose load of about 70 to 75kg.

It yous tows happily at that then thats fine. If you have a stable outfit, adding extra nose load will not have a proprotionate increase ]in safety margins, but it will add extra laod to the car suspension for no real gain.

 

[Gagakev]

Hi Prof,
Tow Hitch = 100kg
Tow Ball =105kg
MPLTM = 1700
So you are saying it's ok to tow at around the 70-75kg mark. ( I have read and understood your signature he he)
Its just the previous van was 1275kg and i used a nose weight of 80-85kg and found that to be a good stable tow
so thought I would try and stay around the same margin, Its just what I felt comfortable with.

 

[Lutz]

I hope you don't mind me throwing in a comment. I think that John was implying that 70-75kg noseweight shoud be adequate, bearing in mind that lots of caravans of the same weight are being towed quite safely by vehicles that have a 75kg noseweight limit.
My own car has a 2000kg towload limit, but the noseweight must not exceed 80kg.

 

[Gagakev]

Hi Lutz, the more comments the better,
Thanks for the input and it seems I am worrying tooooo much.

But here's a thought, if the MTPLM is at it's max @1700kg
Min N/W @ 4% = 68kg
Recommended @ 7%= 119kg (Obviously illegal due to tow hitch and ball weights)
So I could technically go betwen the 68kg and 100kg.

 

[Lutz]

That 7% formula seems to have originated straight out of the blue. No-one has ever explained how it was arrived at or why 7% is better than 8% or 6%. I imagine that someone, a long time ago before there was anything better to go by (no EU Directives, no manufacturer's limits), thought 7% was about right (which it probably was at a time when caravans were, on the whole, a lot lighter) and this has been carried over over the years without anyone really questioning the sense of it all.
The 85% weight ratio "rule" is a bit like that, too. I wonder who determined that stability is seriously threatened if that magical figure is exceeded. I have yet to see any proof. Not that I'm condemning it, but it does seem a bit meaningless without convincing arguments to support the recommendation.

 

[Gagakev]

Lutz, think it's that operative word GUIDANCE note.
I work in the scaffold trade and most of our H + S info start with those words GUIDANCE Note.
So the argument from the lads is "its only a guidance note" which technically they are right.
But if say for example they dont wear there harness when the Guidance note says so, it is a sackable offence.
So who is right and who is wrong??????

 

[Gafferbill]

....... whatever you move from your rear under bed storage to the front will have a ' Double Whammy' effect on your nose weight.
I agree with your first instincts Gagakev..... the higher the nose weight the better, within the limits of your outfit.

 

[colin-yorkshire1]

hi all.
personally I would not worry too much if the noseweight is under by too much as long as the unit is stable and rides ok.
mine is about 20kg under max for the car @ 55kg and seems about right given the loading in the van and car it also reduces pitching a fair bit and the van seems to sit better on the bar.

 

[Lutz]

Lutz, think it's that operative word GUIDANCE note.
I work in the scaffold trade and most of our H + S info start with those words GUIDANCE Note.
So the argument from the lads is "its only a guidance note" which technically they are right.
But if say for example they dont wear there harness when the Guidance note says so, it is a sackable offence.
So who is right and who is wrong??????

But even guidance should be based on information which can be substantiated by facts or at least convincing judgment. However, I've never come across either. Nowhere is there any basis to be found that says, for example, by how much the risk of instability increases between an 85% and a 100% weight ratio. If it's only marginal, then the 85% recommendation has little or no justification. If it's significant, like double, then there would be more point in heeding the 'guidance'. But there's nothing tangible to help one make one's own decision.
In the case of wearing a harness above, the risk is much more obvious as it's a case of black or white. In the case of caravan weight ratios one is in a very grey area. But how grey is it?

 

[Cruzer]

Gagakev, so you've managed to get it to around 75kg, how does it tow at that weight? If it's ok i wouldn't go out of my way to try and get it higher.

 

[Gagakev]

Hi Cruzer, havent towed with it at that weight yet just getting it ready for the off tomorrow.
Confession time; When I towed it home from the dealer last time i have to admit i did'nt weigh it because the gauge I had with me was covered in grease from prevoius tow ball. I did however lift the A frame with a bit of effort. Did read somewhere that if you could do this
it would suffice as a temp measure. (Waiting for the onslaught)
However, would like to be some where near the correct weight, hence the original question.

 

[ProfJohnL]

Hello Kev,
I hope your questions have been answerd by the other correspondents, but close th circle on your post of Thu, 21/04/2011 - 8:26am,

I cant give you a "yes or no" answer to the specific question "So you are saying it's ok to tow at around the 70-75kg mark." All I can say is that if your outfit is easy to tow without undue evidence of instability with a nose load between 70 to 75, then the answer is yes, But as i said in my first reply, each outfit (even the same models of car and caravan but with differnt owners and thier loading arrangments and driving habits etc) will display differnt charateristics.
Lutz has quite correctly pointed out that your model of caravan is probably towed very happily by many motorists who only have a 75Kg upper limit, so there is every chance it will be fine. Carefuly try it and see.
It would be lovely if there were some formula that you could use to tell you if you outfit was good or not, but the fact there isn't demonstrates how variable these things can be. That's one of the reasons why I and some others so stronly argue against the oft sugegsted 7% and 85% figures so often misquoted and misused as "rules"
Its worth noting, that some outfits may tow well on the way to site, but are less good on the way back or vica versa, It very likely the fact that the loading is different on the return journey, thisngs like less gas less food, perpaps the toilet cassette is full, the childrens collection of beach stones, or the awning or poles is not quite in the same position, etc Its unlikely any one of thse by them selves would cause a major problem but a combination might. Its just worth noting.

 

[TD42]

Hi Lutz, Just for infomation,CCs & C&CCs tow car off the year tests are all carried out with the 7% noseweight formula. they have a special unit much like an engine removal hoist with which they check all caravans are loaded to a 7% nose weight.one would assume that each car tested must be coupled to a suitably loaded van??
this seems to be where the 7% formula is derived from

 

[Lutz]

Yes, but both the CC and C&CC must have got the 7% from somewhere. Someone must have determined it in the first place and it would be worth knowing what they did to arrive at that figure.
Somehow I doubt whether the CC and C&CC still use it in their tests as 7% would limit the average family car with a 75kg max. noseweight to a caravan weighing less than 1100kg but most today are heavier than that.