Twin axle noseweight

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Nov 6, 2005
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Prof John L said:
We have been through the aerodynamics debate before, and my own thoughts on the matter agree with Roger L's comments regarding the Swift airflow study, basically the issue is so full of different variables depending tow vehicle types, such that little value can be extracted that would significantly influence caravan design.
That was Swift's stance in the 1970s - their recent fluid dynamics study has shown them which factors are consistent regardless of towcar and caravan length - their current Challenger and Conqueror design incorporates specific features from the study which give them a claimed 10% reduction in drag compared to a Bailey Pegasus II. They've stated that future models will incorporate additional features.
 
Mar 14, 2005
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One should not forget that a caravan is basically a big box on wheels and, as such, has a drag factor probably of around 0.8 or more compared with a modern car of less than 0.3. Therefore, even a 10% improvement is not particularly earth shattering in absolute terms.
The only measure which would offer a really major improvement is to reduce the overall height of the caravan to below roof level of the towcar, i.e. like a folding or pop-up caravan.
Theoretically, it would be possible to compensate for reduction in noseweight with increasing speed even without aerodynamic improvements. One alternative would be to move the caravan axle backwards relative to the chassis frame as the speed increases. Obviously, such a solution would be very involved and costly, but technically possible, nevertheless. A movement of a couple of inches would probably be sufficient.
 
Aug 4, 2004
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Okay hitched up to day etc. Firstly checked caravan in situ and it was very close to level. Raised it and placed it on Reich TLC. Nose weight read 95kgs. This seems to be about 4 - 5 kgs less than when usingt he bathroom scale. Height of towball almost 19 inches, but when caravan hitched up minus TLC towball height approximately 15.5 inches. Caravan showing as slightly nose down when checking level. Took it down rough A road, smooth A road onto M5 motorway. Towed like a dream with no pitching etc.
Reich TLC a lot easier to use than a conventional methods and also very easy to read. I would recommend the product.
 
Aug 4, 2004
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It also resolved a nearside ext mirror problem. I always maintained that having a nearside ext mirror made very little difference. I fitted one yesteday and it made very little difference as it is clamped onto the mirror casing which does not move and by nature is at a sharper angle towards the body of the vehicle. It did allow me to see slightly more, but the difference was negligeable.
I am confident that as I have adequate vision on the nearside of the vehicle with the normal mirror I am operating within the law as the legislation is not very clear. It is also very difficult to find the exact legislation regarding mirrors, but I guess this would be dredging up an old thread.
 
Nov 6, 2005
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It's easy to apply logic to towing mirrors - if the mirrors don't project beyond the width of the caravan you can't see both rear corners of the caravan - and if you can't see both corners you have an increasing cone of blindness behind you.
By fitting mirrors which do project beyond the width of the caravan you give yourself the BEST field of view behind you.
With apologies in advance to Prof John and anyone else - sod the law, we should all get and use the best vision - if that's more than the law requires as a MINIMUM (however vaguely worded) then it's a good thing.
 
Jul 15, 2008
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…….unless the towing vehicles mirrors project beyond the width of the caravan then they cannot comply with the law.

They will not give the prescribed field of view that the law requires.
 
Nov 6, 2005
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Prof John L said:
Hello Roger,
Why do you feel the need to appologise?
To pre-empt you having a go at me for "sod the law".
The problem with slavishly sticking to the law is that many people lose sight of common sense.
 
Aug 4, 2004
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RogerL said:
It's easy to apply logic to towing mirrors - if the mirrors don't project beyond the width of the caravan you can't see both rear corners of the caravan - and if you can't see both corners you have an increasing cone of blindness behind you.
By fitting mirrors which do project beyond the width of the caravan you give yourself the BEST field of view behind you.
With apologies in advance to Prof John and anyone else - sod the law, we should all get and use the best vision - if that's more than the law requires as a MINIMUM (however vaguely worded) then it's a good thing.
If I was to stand at the rear nearside corner of my caravan and look down the nearside I probably would not be able to see the nearside ext mirror. However if I moved a foot away from the caravan, no problem. In order to see the ext mirror when standing at the rear corner, the mirror woudl need to project out from the vehicle body by more than the maximum allowed for a projection. Catch 22!
 
Nov 6, 2005
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Surfer said:
If I was to stand at the rear nearside corner of my caravan and look down the nearside I probably would not be able to see the nearside ext mirror. However if I moved a foot away from the caravan, no problem. In order to see the ext mirror when standing at the rear corner, the mirror woudl need to project out from the vehicle body by more than the maximum allowed for a projection. Catch 22!
There's no Catch-22.

Towing mirrors are allowed to project beyond the width of the trailer by the permitted projection - when you unhitch then you must remove the towing mirrors if they project beyond the car body more than the permitted amount.
 
Aug 4, 2004
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RogerL said:
Surfer said:
If I was to stand at the rear nearside corner of my caravan and look down the nearside I probably would not be able to see the nearside ext mirror. However if I moved a foot away from the caravan, no problem. In order to see the ext mirror when standing at the rear corner, the mirror woudl need to project out from the vehicle body by more than the maximum allowed for a projection. Catch 22!
There's no Catch-22.

Towing mirrors are allowed to project beyond the width of the trailer by the permitted projection - when you unhitch then you must remove the towing mirrors if they project beyond the car body more than the permitted amount.
Still is a Catch 22 as you cannot get a pair of mirrors with one having a longer reach than the other.
 
Apr 7, 2008
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Surfer said:
Still is a Catch 22 as you cannot get a pair of mirrors with one having a longer reach than the other.

Try a pair of milenco-grand-aero-towing-mirror they are easy to adjust,
Or you could use a pair of these to get that bit further out & get the extra angle
smiley-undecided.gif

For your truck, your mirrors may project up to 20cm.beyond the widest point of the caravan.
I can see everything ok when towing a 2.3mtr wide van
smiley-wink.gif
............
& my towball is central
smiley-foot-in-mouth.gif
smiley-laughing.gif
 
Aug 4, 2004
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Sproket said:
Surfer said:
Still is a Catch 22 as you cannot get a pair of mirrors with one having a longer reach than the other.

Try a pair of milenco-grand-aero-towing-mirror they are easy to adjust,
Or you could use a pair of these to get that bit further out & get the extra angle
smiley-undecided.gif

For your truck, your mirrors may project up to 20cm.beyond the widest point of the caravan.
I can see everything ok when towing a 2.3mtr wide van
smiley-wink.gif
............
& my towball is central
smiley-foot-in-mouth.gif
smiley-laughing.gif
Thanks for the links. The mirrors are Pyramind mirrors and are very similar to the Milenco mirrors. I doubt if they woudl make mmuch of an improvement. The only issue is the nearside as I cannot see down the side of the caravan, however the view that I have is more than ample for safety purposes as I cna see 40 metres or more down the nearside.
 
Aug 25, 2010
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After towing with various types of mirrors for the last 30 odd years I have found the Grand Aeros to be the best I have used and have no problems seeing the back corner of by 2010 Delta when they are adjusted to the full width. With the standard Aeros I didn't have such a clear view.By the way Surfer your findings about the Reich noseweight device toes in with what I have found and that is it constantly reads 5 - 6 KG lighter than mean using the bathroom scales method. My guess is the bathroom scales are possibly out by a couple of kgs and the figures I have tie in with your 4 - 5 kg that you have found. At least you took the effort to test rather than go with the various theoretical possibilities. It would be a nice little exercise for PC to run a lab test aver a range of caravans to validate the findings and to finally dispel the fud factor and old wives stories about noseweights. /p>
 
Mar 14, 2005
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Hello Graham,

You state:
"At least you took the effort to test rather than go with the various theoretical possibilities. It would be a nice little exercise for PC to run a lab test aver a range of caravans to validate the findings and to finally dispel the fud factor and old wives stories about noseweights."

Let me first assure that the possibilities are more than theories, they are based just as much on real testing as Surfers and your own results. The theories support the findings which show that twin axle nose weight is a complex issue and there is no simple relationship between hight difference and weight difference for TA's.

The results that both you and Surfer have demonstrate there are differences in the readings depending on the method used. However I cannot make the same assumption that the error is only a few Kg. It depends on exactly how you made the measurements. The differences may be much bigger compared to the measurement at the ride height of the coupling which is where the limit is applicable.

There would be no practical results produced if anyone tested the nose weights of a selection of caravans, as the noseweight changes when loads are added or moved inside a caravan,and they also depend on the measurement height.

I'm sorry but your ill advised if to make simple assumptions about TA nose weight measurements.
 
Dec 30, 2009
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You may not be able to buy unequal length mirrors, but my pair of mirrors can be slid in/out on the fixing rod that goes along the top of the door mirror,( held by clamps to the top of the mirror frame and a strap down the back). I extend the nearside mirror more than the offside one, as the angle of sight of each is different, given my position relative to each mirror. And my towball is central (on the towcar, but not on my ride-on mower!)
 
Aug 4, 2004
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Prof John L said:
Hello Graham,

You state:
"At least you took the effort to test rather than go with the various theoretical possibilities. It would be a nice little exercise for PC to run a lab test aver a range of caravans to validate the findings and to finally dispel the fud factor and old wives stories about noseweights."

Let me first assure that the possibilities are more than theories, they are based just as much on real testing as Surfers and your own results. The theories support the findings which show that twin axle nose weight is a complex issue and there is no simple relationship between hight difference and weight difference for TA's.

The results that both you and Surfer have demonstrate there are differences in the readings depending on the method used. However I cannot make the same assumption that the error is only a few Kg. It depends on exactly how you made the measurements. The differences may be much bigger compared to the measurement at the ride height of the coupling which is where the limit is applicable.

There would be no practical results produced if anyone tested the nose weights of a selection of caravans, as the noseweight changes when loads are added or moved inside a caravan,and they also depend on the measurement height.

I'm sorry but your ill advised if to make simple assumptions about TA nose weight measurements.

You do not have a twin axle and you do not have a Reich Towball Load Control so I cannot understand how make comments about being ill advised unless I am mis-reading your post. If any one is ill advised it is you as you have no experience with the Reich TLC and twin axles therefore you are making assumptions. Others on this forum have found the Reich TLC to be very effective and fairly precise.
 
Mar 14, 2005
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Hello Surfer
you say;
"You do not have a twin axle"

Incorrect, as I have stated on several posts I have TA box trailer. and whilst I choose not publish my current caravan outfit, I have had both SA and TA caravans, and I have towed with many different vehicles, including 5th wheel set ups.

You go on to state;
"and you do not have a Reich Towball Load Control so I cannot understand how make comments about being ill advised unless I am mis-reading your post."

This is partly correct, I do not have, and have not used a Reich device, but the reason for that is I know how they work, and I know the additional height they give to coupling means they do not measure the actual noseweight applied to the tow vehicle. This is particularly pertinent and important to TA's.

You continue;
"If any one is ill advised it is you as you have no experience with the Reich TLC and twin axles therefore you are making assumptions."

Surfer, as you don't know me or my experience or qualifications, you cannot verify one way or another your written statements about me.

Finally you state;
"Others on this forum have found the Reich TLC to be very effective and fairly precise"

That statement can only be true if the same people have made proper comparisons with devices of know accuracy and taken measurements with the hitch at ride height. No other comparison can be assumed or used to confirm precision.

The only safe way to measure noseweight is to have the hitch at ride height. Any other height gives an inaccurate reading.
 
Aug 4, 2004
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Strange as in an earlier post I thought you indicated that you now had a single axle. BTW in case you never realised it, I would say there is a big difference between a twin axle trailer and a caravan unless it is a horsebox.
When you have used the Reich TLC please feel free to comeback and add a really constructive comment instead of a long boring dialogue that only serves to confuse every body at times. Would you liek to borrow mine?
 

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