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Quote: Originally posted by Greendemon315 on 13/3/2013

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I can confirm that. I've had a separate control as well.

Beanpark, yes it does.

For anyone wondering, Nader the in was originally typed as under the sun.   iPad with a mind of its own. Sorry.

Jim

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So do you think the 85% rule is as relevant these days with modern technology?

My answer is no, as you've already said both cars and caravans have come on leaps an bounds since that rule was introduced and legally you can tow right up to 100% unless a limit is in place.  Regarding the 2 cars your looking at you may find that if you were to weigh them on a bridge they could be heavier than the brochure weight, remember the higher the spec the heavier the car. 

The brochure weight for my car is 1557 kg towing a 1500kg caravan makes it a 96% match on a weigh bridge the car weighs in at 1630 empty add the 75kg driver as per european guidlines takes my match percentage to 87% perfect.

if you are confident in your outfit then just go for it, I used to tow with a s max which was  heavier than my mondeo and would sing it praises all day long however my mondeo is far more stable than the s max ever was. I think this was due to the higher car body, going past a HGV and then being overtaken by a large van (sprinter)  or coach in the outside lane would be a a##e twitching moment to say the least  the mondeo never budges

bessie    

Quote: Originally posted by beanpark on 13/3/2013

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So does that mean the lower it is down from 85% the better

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Basically yes as it's all about balance. If you imagine a see-saw with equal weight both sides, the plank will be horizontal which is identical to a 100% ratio match of car and caravan combination. The 100% match in theory is based on this principal so this helps to understand more the way it works in terms of a balanced weight. So, if you reduce the weight on one end of the plank then the balance alters respectively which in theory is the same principal in terms of the 85% guide. Also if you get two blocks of the same size in volume, one made of light wood and the other made of metal, connect the two by a short length of string in the middle and firstly pull the combination with the wooden block with the metal behind then do it the opposite way around and ask yourself, which of the applications felt more stable of the two? The answer will be that the combination with the heavier block pulling the lighter one was more easy to control. The light one will actually pull the heavier one but if you violently sway the front one (identical to a snake) then the rear block being heavier will eventually take control of the lighter one in front. The debate constantly goes on about what's right and what's not regarding a safe match but the science behind the 85% rule has been mathematically tested for our safety so basically to put it in a nut shell you either take the advice or you don't. But don't let your ignorance just leave it at that, do your own basic test and work it out for yourself. At the end of the day it's not only your own life you are putting at risk plus others road users and pedestrians too so the choice is yours whether you try to achieve a sensible match or not. 

WRONG trailer brakes can be applied independently of the tractor .
I my learned freind hold a class 1 and have done for 30+ years and the unit that I drove untill i retired had a trailer brake on the dash which applies
the brakes on the trailer independently of the tractor IF REQUIRED
The foot brake applies the lot
Some of the newest tri axles DO have an ABS sensor on every axle


Ok the brake that your refering to is the jake brake/exhaust brake/engine brake, this is unit only nothing to do with trailer as it doesnt apply the trailer brakes it's designed to slow you down when your brakes start overheating. i learned all about that 23 years ago when i passed my hgv class 1

Regarding the 6 abs sensors we've got a fleet size of 10,000 trailers and tankers all with 2 sensors , no need for 6 sensors. The axle with the sensors on set the braking for the whole trailer i learned about that when training to be a trailer fitter

A compression release engine brake, frequently called a Jake brake or Jacobs brake, is an engine braking mechanism installed on some diesel engines. When activated, it opens exhaust valves in the cylinders after the compression cycle, releasing the compressed air trapped in the cylinders, and slowing the vehicle.

Although Jake brake properly refers to the Jacobs brand of engine brakes, the term has become a genericized trademark and is often used to refer to engine brakes or compression release engine brakes in general, especially on large vehicles or heavy equipment.

Bessie  

Quote: Originally posted by bessie500 on 13/3/2013

WRONG trailer brakes can be applied independently of the tractor .

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I my learned freind hold a class 1 and have done for 30+ years and the unit that I drove untill i retired had a trailer brake on the dash which applies
the brakes on the trailer independently of the tractor IF REQUIRED
The foot brake applies the lot
Some of the newest tri axles DO have an ABS sensor on every axle


Ok the brake that your refering to is the jake brake/exhaust brake/engine brake, this is unit only nothing to do with trailer as it doesnt apply the trailer brakes it's designed to slow you down when your brakes start overheating. i learned all about that 23 years ago when i passed my hgv class 1

Regarding the 6 abs sensors we've got a fleet size of 10,000 trailers and tankers all with 2 sensors , no need for 6 sensors. The axle with the sensors on set the braking for the whole trailer i learned about that when training to be a trailer fitter

 

A compression release engine brake, frequently called a Jake brake or Jacobs brake, is an <A title="Engine braking" href="http://en.wikipedia.org/wiki/Engine_braking">engine braking</A> mechanism installed on some <A title="Diesel engine" href="http://en.wikipedia.org/wiki/Diesel_engine">diesel engines</A>. When activated, it opens <A class=mw-redirect title="4-stroke cycle engine valves" href="http://en.wikipedia.org/wiki/4-stroke_cycle_engine_valves#Internal_combustion_engine">exhaust valves</A> in the cylinders after the compression cycle, releasing the compressed air trapped in the cylinders, and slowing the vehicle.

Although Jake brake properly refers to the <A title="Jacobs Vehicle Systems" href="http://en.wikipedia.org/wiki/Jacobs_Vehicle_Systems">Jacobs brand of engine brakes</A>, the term has become a <A class=mw-redirect title="Genericized trademark" href="http://en.wikipedia.org/wiki/Genericized_trademark">genericized trademark</A> and is often used to refer to engine brakes or compression release engine brakes in general, especially on large vehicles or heavy equipment.

Bessie  

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Quote: Originally posted by tango55 on 13/3/2013

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Quote: Originally posted by beanpark on 13/3/2013

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So does that mean the lower it is down from 85% the better

---

Basically yes as it's all about balance. If you imagine a see-saw with equal weight both sides, the plank will be horizontal which is identical to a 100% ratio match of car and caravan combination. The 100% match in theory is based on this principal so this helps to understand more the way it works in terms of a balanced weight. So, if you reduce the weight on one end of the plank then the balance alters respectively which in theory is the same principal in terms of the 85% guide. Also if you get two blocks of the same size in volume, one made of light wood and the other made of metal, connect the two by a short length of string in the middle and firstly pull the combination with the wooden block with the metal behind then do it the opposite way around and ask yourself, which of the applications felt more stable of the two? The answer will be that the combination with the heavier block pulling the lighter one was more easy to control. The light one will actually pull the heavier one but if you violently sway the front one (identical to a snake) then the rear block being heavier will eventually take control of the lighter one in front. The debate constantly goes on about what's right and what's not regarding a safe match but the science behind the 85% rule has been mathematically tested for our safety so basically to put it in a nut shell you either take the advice or you don't. But don't let your ignorance just leave it at that, do your own basic test and work it out for yourself. At the end of the day it's not only your own life you are putting at risk plus others road users and pedestrians too so the choice is yours whether you try to achieve a sensible match or not. 

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Thanks Tango that is exactly what was needed to get a picture into my own mind to see. I knew that it had to be balanced that is why I bought my Bob bits & pieces for him to be able to get the nose weight right. Between us it works well. We both check the unit to see if it looks straight right through. Very conscience of putting the awning & poles over the axle and follow the diagram of what to put where shades of colour.

We have a Skoda Yeti 2.0 and pull a 2 berth Lunar which is 1000kg without the rest. It is very easy & smooth riding and hills never bothered us. But as not very technical I have never really understood this 85% and I asked Bob and even though we have towed since 1964 various things we must of been doing ti right as we have not had a problem, then we have never taken the everything + the kitchen sink with us.

Now we have a clear picture of what is what.

Thanks again.

Chrissie

Were not talking about jake brake ,engine brake nothing to do with that .
Go an check yer facts , I can remember having a tractors that had an independant lever on the dash that applied the trailer brakes independantly .
If pulled on fast it was possible to lock the wheels up on the trailer and on release you could hear the air releasing on the trailor.
I could stop on an incline and without touching the handbrake the trailor brake would hold you secure.
I'll give you a clue the badge on the front had 92m   " long before your day"

Ok i'll take your word for it an old 80/90's scania may well have a trailer lever on the dash but they certainly don't now i've had 6 drivers in here today and asked them all if the could operate the trailer brakes via the cab. I even asked the guy from vosa as he's onsite MOTing  trailers/units all looked at me blank

Fact is to stop a caravan or hgv it's the same process.......you jump on the middle peddle

Greendemon315 the problem with caravans these days is they are just getting heavier and heavier thats why the question keep popping up as people are getting caught out, so yes if you've never towed before 85% is a great guidline but thats all it aint law, once you have experiance then its up to you.

The fact  is the op was asking as he was comparing 2 cars, my advice is only he has the  answer if your confident in your own ability then go for it, I always advise people to weigh their cars 1st as your risk element could be greatly reduced.

Bessie              

Thats what they include empty car 90% fuel + 75kg driver gives you true kerbweight.

The brochure weight already includes 75kg driver in the published weight

bessie