Single or twin axle?

[Lutz]

You've lost me now, Jason. You said yourself, quote."....the twin is a far better tow and far safer .....". I was just replying that a single is not unsafe and now you're dismissing the argument. Other than that you have not mentioned one convincing reason why a twin is better. What then is so much better if it's not the safety aspect?

 

[Hamer_5041128]

Jason R,

In all my years of caravaning i have never met anyone who arriving on site gets in their caravan ,moves everything to the rear to move the caravan.

Myself and all my caravaning friends prefer a relaxing holiday, nearly all have motor movers fitted, but as i said it is a matter of choice.

Hamer

 

[Clive-Cardiff]

While I agree with a lot of the points that Lutz has made, I think that comparing the stability and load carrying of a commercial vehicle with a caravan is not really valid.

Caravan suspensions are really a lightweight solution to the needs of the caravan. Most vans use the Al-Ko chassis which relies on rubber bushes to do the job that on a commercial vehicle is done by a complex suspension with shock absorbers.

I have read that a caravan relies as much on the tyre pressure as the suspension to cushion the ride.

The other point I would make is that manufactureers will fit a tyre on a van that is just within the weight range, because it's cheaper.

This meant on my last van that the tyres were running on the maximum pressure and maximum loading.

 

[JasonR_374341560]

Are you two on something strong?

One thing being "safer" does not make another thing a danger!

You don't have to move "everything" either Hamer. I can assure you that being retired we take things easy and we've only rarely used the up jockey wheel tactic. But the odd little trick is a useful aid.

I prefer to spend money on other things and maintain my vans carrying weight, you say you need a mover Hamer and thats fair. I can assure you that a mover is not essential equipment and in many instances it seems to be wastefull one upmanship status symbol, nmany would do better spending the money on their van or tow car.

 

[Lutz]

If the tyre equipment that the caravan manufacturer has provided is on the limit, Clive, then that is something that he is accountable for and cannot be used as an argument against a single axle, in principle. If the tyre equipment (and the chassis design) is appropriate to the demands, as in the case of commercial vehicle trailers, then I see no reason why a single axle is any worse, on the whole. And there is also no reason why caravan manufacturers should not be able to follow the same design principles as their bigger counterparts.

Maybe some people set their priorities concerning the advantages and disadvantages of the one vs. the other differently and therefore prefer a twin to a single, but that doesn't mean that the twin wins hands down. After all, a second axle must weigh more and it doesn't come for free, quite apart from the well-known issue concerning poorer manoeuvrability by hand. When comparing apples with apples, the only real advantages that I see of a twin is that it, by principle of its design, should have better braking performance and may have have marginally better straightline stability, but at a price. If the twin were really the best thing since sliced bread, then why is the proportion of really heavy single axles increasing all the time? Many years ago, most caravans over 1400kg were twins, but today even an 1800kg single is no longer unusual.

 

[Moderator2_5083849]

Please keep the debate about the merits of twin vs single axle vans.

There is no need, nor will it be tolerated, for silly personal comments to come into topics.

 

[ValA.]

Doesn't the basis of this question go back to size, layout and towability. Barry was looking for a van which could accommodate six people. In the UK twin axles are generally bigger with more internal room, therefore a van layout accommodating six people in comfort is more likely to be bigger, and therefore more likely to be a twin axle. Towability depends upon the van and the towcar - and if you have anything other than a 4X4 of a decent kerbweight then you're not likely to find a twin axle that you can tow safely. (Although we did see an old twin axle in France, once, which was about three feet shorter than our current 490)

As a generalisation I imagine the main reason people have single axles is that they need (or can manage with) less room. This is also likely to mean that the caravan can be towed with a smaller car, meaning less 'on the road costs'.

 

[Del_374232870]

As others have said there are advantages and disadvantages to both single and twin axle vans. Towing experience is also something to take into account, if you have very limited or no towing experience do you want to take the plunge and go for 27 ft 1900kg twin also is your tow car suitable for a big van. You may wish to consider towing classes if your towing experience is nil or limited,

We started of with a small Sprite (14ft over hitch) and I can still remember that first tow, From there we gradualy moved up to our current 26ft t/a. Interestingly whilst I will say that when well loaded the t/a is the most stable van to date, our last s/a which was a Lunar Lexon EB was also very stable on the road when well loaded. We use the van 12 months a year and it is windy conditions that I really feel the improvement, the extra pair of wheels and weight means very little tail waging saying that if I don't load it correctly I soon notice it.

I would 1st look at the limiting factors of the potential new van and wouldn't go for something unless I was confident with it and confident in myself towing it.

As for manoeuvring, yes twins can be more difficult to manoeuvre of the car but I find reversing with the twin to child's play as te van is less responsive to slight steering movements and easier to keep in a straight line. We have a mover fitted to our van but in the last year have only had to use it once, and that was to get it into a pitch at Rothiemurchus (pitch we always choose) which is surrounded by pine trees and impossible to reverse into with either a single or twin.

 

[Lutz]

Not quite, Val. Only the very biggest caravans actually need a second axle because of their size. For the vast majority, a twin is just a matter of preference. There are plenty of models up to and including the 580's with just a single axle and that probably covers more than 90% of the market.

 

[Dustydog]

Barry wants to know which way to go. He has the car & the budget so cost and weight don't come into it.

I've towed both and will say a good modern correctly loaded sa is safe. However I do find the ta more stable in cross winds and when being overtaken by those express coaches.

My faithful Pageant tyre pressures were nearly at the maximum pressure permitted ie 42 psi. No problem because the tyre is designed for that psi at top speed 24/7. However the ta psi is 28. As far as I can tell the tyres are the same so it follows my ta tyres are not as highly stressed etc. And so the semantics continue.

Barry, with your circumstances go for space and luxury and have a ta. You will not regret it. It is the luxury end of the market and that's why there are more sa vans about. I agree with Lutz percentages but why can't you and I be part of the 10%?

Cheers

Alan

 

[Lutz]

Don't get me wrong. I'm not hitting out at twin axles, in fact, in my previous replies I have mentioned a couple of advantages. But, contrary to Jason's remarks, I'm saying that the single axle has just as many advantages, so it's up to everyone to weigh up the pros and cons against one's own priorities and then decide. The result cannot, however, be a foregone conclusion (unless you happen to be in the market for a caravan which is so big that a twin is unavoidable, but that starts at over 1800kg or around 25').

 

[JasonR_374341560]

T/A eliminates much of the pitch/yaw that you get with S/A.

T/A rides imperfections such as pot holes better than S/A

T/A design gives resistance to lateral/sideways movement, a "natural" damper.

T/A does not mean twice the axle/chassis weight. T/A design enables loadings to be better distributed.

T/A wants to track in a straight line a single will wander where it wants, this natural tendency of the twin helps keep you out of trouble.

Comparing T/A van to 4 engine transatlantic aircraft is nonsense. The aircraft argument is to do with reliability and probability re engine failure.

There are other braking and handling advantages of twin over single, even tyre types give twins a better ride and inflict less shock on the caravan.

Cars are designed to carry people in comfort, towing is an after thought. Commercial trailers towed by commercial vehicles with harder suspension more suited to the job in hand is a long way from a Laguna towing a caravan with family and two weeks of their needs crammed in to car and caravan and commercials are unlikely to be towed at the speed many car/caravan combinations can attain.

Whilst on commercial trailers. The majority are twin axles!

Whatever van you choose, badly loading or over loading is a no no, and towing stability electronics in car or caravan do not mean you just throw what you want anywhere in the caravan with hope and the belief that a chip will save you if something untoward happens.

We've towed for long enough to know how to load a van and have gone to twin axle and back to single and now with fourth twin axle, the third since getting rid of the last single.

If you want to believe theories and speculation that single axle is as good for towing as twin. Enjoy the dream.

And no doubt Reliant Robins were as good as 4 wheel cars

 

[Lutz]

I challenge you to produce any quantifiable data to uphold your statements, Jason. I strongly suspect that all the reasons given are purely speculative based on your own perspective. If your arguments were so overwhelming, as you state them, then large single axle caravans would have disappeared from the market a long time ago. However, quite the opposite is true. More and more are appearing at the top end of the size scale. Like I said, 1800kg 25' single axles are not unusual any more.

 

[Dustydog]

Lutz

I think Jason has given a pretty fair overview. I cannot disagree with his findings in fact most I have experienced and believe correct. Ok so there is no Professor of caravan technology Uni of Bath to support the views but they do not seem flawed to me.

As far as I am aware the Swift single 540 comes in at 1600kgs. I haven't seen the type you mention which is more heavy than my Wyoming and only 11 inches shorter. Must be one mother of a van.

Personally at that sort of weight I think I would give it a miss an dstick with a twin.

I do like singles and have owned a number , no problems but a single at 1800kgs seems topushing the boundaries of science to me.

So do we tell Barry to go for a massive single or twin axle??

That was his original question!

Cheers

Alan

 

[Del_374232870]

I am interested to find out which single axle van weighs in at 1800kg and 25ft long. Not saying there aren't any but cant recall seeing any

 

[CarolineSimon]

" I do like singles and have owned a number , no problems but a single at 1800kgs seems topushing the boundaries of science to me.

So do we tell Barry to go for a massive single or twin axle??

That was his original question!"

Hmm,

We have a S/A 1800kg 2007 UK model Burstner & its not even close to pushing the limits!

 

[Dustydog]

Caroline

You mean they even have bigger heavier ones?

I am amazed.

What model is yours?

Chers

Alan

 

[JasonR_374341560]

"I challenge you to produce any quantifiable data to uphold your statements"

What utter garbage, and caravans are built and sold with the buyers budget and the manufacturers profit margin as a major factor.

I would loook at that before trying to justify a single against a twin.

We and numerous caravanning friends and aquaintances over many years have noted the superior behaviour of twin axle versus twin.

This is a caravan advice forum, most of us give advice based on our experience. I feel that our experience over the years with both singles and twins more than qualifies a valid comparison. Apart from our own caravans we've also towed many other caravans and twins always stood out as a better towing experience.

Sorry Lutz but you are a dreamer, "data" is no challenge for comprehensive towing experience of both set-ups.

 

[Dustydog]

Do I detect an anti twin axle lobby out there?

I hope not!

My twin tows like a dream and is very balanced. Why do I want to have an even heavier caravan on a single axle? I just don't understand the logic? I am sure Swift ,Bailey and others would love a massive Conqueror or Wyoming on a single axle. Think of the savings they could make. So why do Bailey and Swift produce much lighter caravans on twin axles as indeed do a number of other manufacturers?

The thought of a Jumbo jet with one engine doesn't float my boat. Give me a good four engined 747 any day.

Cheers

Alan

 

[RichardS1]

I am aware of some of the top end Hymer and Knaus vns that weigh around 1800kg, however the bodyshells do not appear to be as long as a modern twin.

If you require long front settees, a fixed bed and a spacious washroom for example twin axle are the way to go this layout is not really available on a single axle.

While I said earlier in the thread that out current twin is extremely stable so were all the singles we have owned, so I do not think I could justify owning the twin for improved stability.

I can however justify owing it on increased interior space over any other single axle currently available

 

[CarolineSimon]

Hi Alan

Our Van is a 540TK model on a single axel & is a 5 berth with fixed double bed & fixed rear bunks & small double/large single side dinette all beds sleep adults as well as children.

The layout was the reason we bought it & not how many axles it had which I think is down to personal choice & what van layout you want.

It has had an upgraded chassis as a optional extra put on in the factory when we ordered it so it now has an 1800kg payload.

Funnily enough most of the European manufacturers seem to prefer single axles for the UK market.

Anyway it is well balanced & tows happily so we don't even think about it being on a single axle. That's not to say we wouldn't have one with this layout but none are UK legal as they are all too wide or too long!

Such is life!

Caroline

 

[JasonR_374341560]

That's fine Caroline, we would have said exectly the same about our old single axle caravans. it's just that the twins are still better to tow.

 

[Lutz]

Jason, I am really impressed by the way you avoid answering my question but beat around the bush with 'comprehensive towing experience'.

Let me repeat once more, I am not against the twin in principle. If your priorities are such that the twin meets your needs beter tahn a single, so be it. But to claim that the twin vs. single is a no contest issue that is valid for the whole caravanning community is, to put it bluntly, contemptuous.

 

[CarolineSimon]

I try not to tow it as its blooming massive so makes no odds to me what axles is or has not or how stable it is my darling husband has that job! We are just getting a mover for it so I may well tow a bit but can't reverse to save my life even though I have been on a course!

Joking apart if we could have had this layout in a UK legal twin axle we probably would but it wasn't available and we bought on layout alone so had to have european as no UK manufacturers make this layout.

Caroline

 

[JasonR_374341560]

Lutz. I'm equally impressed with your persistence no matter how you try to twist your argument.

Having owned and towed both styles the way you try and twist the discussion is not valid.

Singles are valid and have their place, the size of van we own and the layout we like has nothing to do with the overall superior towing experience a twin axle caravan provides.

I would just add that my wife and I also collected and delivered caravans in the past.

Twins win Lutz!

If I thought a single was as good and cheaper I would by a single, that is not the case. If I were to downsize to something where twin was not available, I could live with that, but I know that it would be a backwards step in the towing experience and handling on the road.