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Posts posted by Lutz

  1. 3 hours ago, Steamdrivenandy said:

    Obviously actual kerbweight will vary dependant on component densities etc but I can't think that body panel thickness between individual examples would vary by more than a few kg.


    'Max. towing weight - braked 12% / 8% gradient - kg  1,300/1500

    Max. towing weight - unbraked - kg 620

    Minimum kerbweight (with driver) - kg 1,246-1,409 

    Minimum kerbweight (without driver) - kg 1,171-1,334

    Turning circle - kerb to kerb 10.4

    Nose weight - kg 75' 



    For a start, kerbweight is specific to the vehicle in question whereas mass in service isn't.


    The biggest variation that we, as car manufacturers, identified on otherwise identical cars was in the weight of the sprayed underbody protection. Added to that, sheet metal and paint thickness tolerances accounted for a total of up to 50kg variation. Far bigger is the variation due to differences in equipment specification. Even the same model with the same engine could vary by as much as 150kg depending on the level of equipment and none of that would show up in the mass in running order (unless specified as a range, as above).


    Just a note to the quoted figures above, if with the driver it can't be called kerbweight, because kerbweight, by definition, is without the driver.


    2 hours ago, Black Grouse said:


    The Germans use a 100% ratio to determine speed limits under Tempo 100 - go over the 100% and the towing speed limit is reduced to 80 km/h (49.7 mph)


    The above only applies to caravans and specifically to those fitted with dampers. Different values apply for other configurations. They can be as little as 30% (if no dampers are fitted) to 120% (for trailers other than caravans).

  2. Glad we took the decision to break off our stay and return home from Aguilas (only a stone's throw from Villaricos) just before Christmas when the temperatures were starting to drop and fly off to the Canary Islands tomorrow instead, leaving the caravan in winter storage. Maybe it was a premonition.

  3. 1 hour ago, Mr Plodd said:

    I was trying to relate my post to the type of trailer normally associated with caravans and similar rather than “muddying” the waters over different braking systems that, in general DONT get fitted to caravans.


    I must admit my understanding was that they are now banned in Europe, but having said that I certainly don’t have the depth of knowledge on the subject that you have as a result of it being your business! So thank you for the clarification.


    It does seem somewhat perverse that they cannot be type approved but CAN be IVA’d. They are not type approved for good reason and that reason would still exist on an IVA’d one!! But as someone once said “The law is an ass!” 



    The law is there to cater for the vast majority of normal conditions, but there is always a case to allow for exceptions on a case-by-case basis. How else would one be able to allow special vehicles such as mobile cranes for example, which do not comply in full with Construction and Use Regulations? Such vehicles can be approved under an IVA subject to certain restrictions concerning their use on public roads.

  4. 38 minutes ago, Wildwood said:

    As the guy from the insurance company who did investigate the accidents the fact is I have not seen an accident where the driver has lost control of a caravan with a sensible towing ratio. Yours suggestion is at best unwise and could be fatal. I know that sounds blunt but I have dealt with the results.

    Some insurers do limit the loaded weight of any trailer to the unladen weight of the tow car and that can only be based on their accident experience.

    The towing limit is what the car can restart five times on a 12% incline and has nothing to do with safety. Towing a broken down car at low speed around town is very different to a large flat sided caravan around town.


    I would speculate that the insurance companies are not acting on the basis of accident data, but purely on postulation. There simply aren't enough accidents involving trailers to be able to have enough detailed data from which one can come to a reliable conclusion. For instance, how would the insurance company know that poor weight distribution was not the cause rather than the absolute weight of the towed trailer. Also, lack of due care and attention on the part of the driver could be the cause rather than any weight issue. Besides, weight ratio is, after all based on a worst case scenario, but how many vehicles tow a fully loaded caravan with just the driver and no other payload in the car?

    The manufacturer has full product liability within the limits that he specifies and that means not only five restarts on a 12% incline, but also the way in which the outfit handles and its braking performance.

  5. 15 minutes ago, Flying Grandad said:

    Published "kerbwieghts" can be misleading at best. Have a look in you V5 and find your car's Mass in Service. Base your decision (and other calculations such as car payload) on that figure.


    But there is a big difference between kerbweight and mass in service. Mass in service, by definition, will almost invariably be less than the kerbweight even though it includes 75kg for the driver, which kerbweight doesn't.

  6. 32 minutes ago, Jacko1 said:

    OK so, have really looked into this RX450 business, my budget would get me into a MY 17 car. Have just discovered that after MY15 there is NO aftermarket towbar available and nobody can tell me why, is it technical or volume related?.

    The only option is OEM fit at factory and from what I can see a MY17 car with a factory fit towbar is about as rare as rocking horse doo doo....


    Sat here now waiting for a few 'told you so' comments......:P


    Still dont fancy a plug in job, so its back to a dirty diesel option.


    Here's a response from an RX450h owner in the Lexus Owner's Forum which may be of help:



  7. 8 hours ago, AJGalaxy2012 said:

    Why is that? I would have thought the ability to run at a high load for a reasonable length of time would have made that quite a simple installation.

    When the vehicle is running primarily on electric power and the diesel is only charging, but not providing any or much propulsion, the diesel will only be running at relatively light load, a condition that is not encountered so very much with a pure diesel. Emissions control must be specific to take this into account.

  8. 1 minute ago, AJGalaxy2012 said:

    The emissions aspect can be fairly quickly sorted, the diesel engine would start, be run at optimum RPM for all systems, turbo, dpf, catalytic converter etc. It would be run under maximum load avoiding lightly loaded diesel issues and would run long enough to fully charge the batteries again. The system could be made intelligent by use of GPS, if it knows where your destination is and if charging facilities are there it can make the optimum decisions.


    It is very true the petrol hybrid is good at hiding when it's running etc, the Outlander PHEV that we have it's hard to tell when it's running.


    The diesel market issue is only a relatively recent development, hybrids have been around for quite some time.


    True, but a diesel hybrid still requires specific exhaust emissions systems that cannot be transferred directly from an equivalent diesel, so manufacturers will only embark on such a project if the expected sales volumes are large enough to justify the development costs.

  9. 42 minutes ago, AJGalaxy2012 said:

    I have to say Im amazed in the lack of Diesel Hybrids. A diesel engine could be run under it's optimum conditions, plenty of heat fed into the DPF to minimise emissions, batteries charged it could then shutdown, all of the drive being accomplished by electric motors.


    The reason why there are fewer diesel hybrids lies in the high investment costs associated with the development of exhaust emissions control of a diesel in conjunction with hybrid drive. It is much easier, and consequently less costly, with a petrol engine.

    • Like 1

  10. 18 minutes ago, ianbrown said:

    We towed with a Lexus 400h for several years. The caravan was either a Baily Senator Indiana or a Swift  Archway Twywell - both approx. 1500kg. The Lexus towed brillianty so I better explain why we only kept it for about two /three years. The reversing lights were hopeless and made it very difficult to  get in or out of  home and secondly the very small battery under the bonnet was  soon pulled down to about  11 volts if you left an door or the boot open so all the interior lights on! Consequently you could not start the vehicle as this same little battery fed all the relays to allow the large batteries under rear seat to come into play .They needed a fully charged battery to open them.Lexus had the car in several times but could find  no fault . I used to carry  a 12 volt jump-pack  so we would  always be able to  move!! I believe  that both of these design faults were put right on the  450h with a much larger battery and changes to the reverse lights.




    I can't make the same comment about the reversing lights. For me, they were ample to light up the rear adequately on the rear view camera display, but I do agree about the inadequate size of the starter battery (which happened to be identical to the Nissan Micra - a much smaller car).

    A negative comment about the RX400h that I would make, though, would be the very torque sensitive steering, especially when towing. When moving off briskly from traffic lights with the caravan on the back, one had to hold the steering wheel tight in order to stay in a straight line.

    Otherwise it was a very nice car and I have no further reservations about it.

  11. Towload limits are often dictated by engine cooling performance. In the case of a hybrid, which has two modes of propulsion which both have to be packaged under the bonnet, there could be so little air space left in the engine compartment, that cooling becomes a real issue, resulting in a lower towing limit than what one would otherwise expect.

  12. 1 hour ago, Jacko1 said:

    Am seriously looking at the RX450, so it’s good to hear somebody is using a Lexus. Think the RX has a 2000kg limit so is more than suitable as a replacement for our current XC60.


    For over 6 years I towed an 1800kg caravan with a Lexus RX400h hybrid.

  13. 1 hour ago, DACS said:

    Can you be sure that the trailer hitch is completely free of grease?  I grease  the ball when towing my trailer and clean it when towing the caravan, using brake cleaner and paper towels.


    I bought my trailer new so I know that it must be free of grease. I've used it like that for 10 years now without any noticeable wear and tear due to running dry.

  14. 19 hours ago, Jezzerb said:

    We saw a very nasty moment as a caravan tyre burst on an outfit coming the other way-the caravan was all over the place and smoke everywhere-luckily  car driver was going slowly and pulled over safely but it could have been far worse. Scarey to see. Tyres to me area  safety item and always better safe than sorry0if in doubt change them! Well done BTW-sounds a great dealer and I would reward them with my custom eg for servicing etc as much as possible with that sort of treatment!


    I find that rather strange because when I experienced a blowout at motorway speeds I wouldn't have noticed that I had one except for the big bang and seeing bits of rubber flying through the air in my rear view mirror. The outfit behaved absolutely impeccably although  I was towing at 100% weight ratio and I even needed to negotiate a bend in a slip road before being able to come to a halt.

  15. 31 minutes ago, CommanderDave said:


    The extra 54 kg would be part of the combination trainweight however it is carried so he would have to loose 54 kg from the vehicles payload to stay legal .


    But the 54kg (or whatever the noseweight actually is, so it would normally actually be more) are part of the payload so nothing is lost.

  16. 2 minutes ago, CommanderDave said:

    Just knock 54kg off the maximum payload in the car as towing allowances from car manufacturers  are usually based on a fully laden vehicle .


    Check your weight plate .


    The 54kg that you refer to would be the minimum noseweight which one would have to allow for anyway when measuring the car's overall weight.

  17. 40 minutes ago, Oscarmax said:


    Our 2016 Swift Conqueror 480 was  stock model we had to pay for the payload upgrade to 1554kg, however, we are changing our towcar this year, the manufacture has put a 1500kg maximum towing limit, I have contacted Swift they have informed I need to contact my supplying dealer to downgrade the payload to 1500kg.


    Why would you need to downgrade the caravan to 1500kg? Even if it were fully laden to its 1554kg MTPLM you would only be exceeding the towing limit if the noseweight is less than 54kg. The towed load is, after all, only the axle load of the caravan, not its total weight. Besides, the towing limit only refers to the actual load, not the plated maximum, so if in doubt just don't load it right up to the MTPLM.

  18. 1 hour ago, 664DaveS said:

    The suv antis change their tune when there cars get stuck in snow!

    We have rescued a few caravans and a small campervan from muddy pitches!


    33 minutes ago, FrankBullet said:

    Nothing to do with ‘SUV’ and everything to do with tyres and 4wd, the two don’t always go hand in hand



    Besides, it would be rather poor economic strategy to purchase a 4WD purely on the off-chance that one may, once in a blue moon, get stuck on a muddy pitch. If you have a non-4WD you will soon learn the limits of its capability and you will try to avoid pitches that are likely to get muddy.


    ps: It may come as a surprise to know how many SUV's on the road are actually 2WD.


  19. 11 hours ago, Black Grouse said:


    4% is a legal minimum in Europe - the 7% isn't really a recommendation, it's just the maximum a 100 kg hitch limit will permit for most caravans.


    A figure of more than 7% will give better stability but few UK outfits can achieve that because of limitations.


    4% is the minimum that the manufacturer must provide. It is not the minimum that must be maintained in service.

  20. I've only ever changed my caravan due to a change in circumstances. The last change was because the old caravan had bunk beds for the children, but as they now have their own ideas about holidaymaking, it was traded in for a fixed twin bed. I'll probably keep that now for as long as I continue to go caravanning and hopefully that will be a good many years.

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