Ian Barkley Posted June 3, 2002 Share Posted June 3, 2002 I found this weekend when towing if the speed crept up to 70 the trailer would start swaying from side to side, slowing down cured this. It feels quite stable up to about 65 but after being passed at about 80 by similar rigs I feel that something could be improved. Tow car 2 Ltr Audi 80, Brian James Minno with 7 on board. I checked the tyre pressures and set as recommended. Would it be more stable with more wieght on the tow hitch? Should I move the car forward? or back? Any ideas? Thanks Ian Link to comment Share on other sites More sharing options...
tic Posted June 3, 2002 Share Posted June 3, 2002 I've been advised by those in the kno to have weight distributed with approx 50lb bias towards the tow hitch. I've always done this and had no probs (until I loaded it too far back - then it started to swing :-( Also, there are many more ruts on the inside lane... :) Cheers Link to comment Share on other sites More sharing options...
Paul Turner Posted June 3, 2002 Share Posted June 3, 2002 I towed with a Golf for several years and set up the trailer to have the recommended by VW 50kg on the tow ball, it was no problem but on the recommendation of a caravan towing colleague I bought a stabiliser, after using it I would never tow without one. Paul Link to comment Share on other sites More sharing options...
F355GTS Posted June 3, 2002 Share Posted June 3, 2002 Minno with 7 towed by BMW 540 I found the trailer swayed if the car was further back, I now line up the number plate (front of nosecone) with the front crossbar of the trailer and have no problems Mark Link to comment Share on other sites More sharing options...
Alex Birtwisle Posted June 3, 2002 Share Posted June 3, 2002 Be careful as the boys in blue take a very dim view to trailers going over 60mph. The rutting in lane one can sometimes help stop the trailer swinging if you have a wide enough wheelbase and you can drive it straight. And as everyone else says, 50kg at the nose helps balance things. Alex Link to comment Share on other sites More sharing options...
stevefoster Posted June 3, 2002 Share Posted June 3, 2002 Not enough nose weight is the cause of the problem. 50lbs sounds too light to me. My little 1.9D ZX likes about 50kg of nose weight. Max recommened in the manual is 65kg. Get some flat ground and pop some scales under the jocky wheel and move the load (7) until you get a reasonable weight. Also helps to inflate the rear a bit more. The ZX normally runs 2.1 bar rear and I go up to 2.4 bar when towing. Link to comment Share on other sites More sharing options...
Paul Ranson Posted June 3, 2002 Share Posted June 3, 2002 I think nose weight is a bit of a red herring as long as you have some. Park on flat ground, drive onto the trailer, the right place is when the back of the tow car starts to dip. A few inches either way don't matter. I found with a Minno and Audi A4 loaded with a Caterham that it was stable up to 80. What usually causes stability problems (IME) is weight at the ends. If you move the weight on the trailer towards the front or rear (regardless of the resultant nose weight) then the moment of inertia is increased, which reduces the natural frequency of the trailer about the tow hitch. So it will be more prone to waggles. So if you've loaded your tools and wheels onto the front of the trailer, and moved the car back to compensate that might be bad. But in the end, you cannot safely tow at speeds over 70mph, and apart from the legalities and safety issues it costs a small fortune for any decent distance. Get used to cruising at 65mph and swapping drivers without stopping... Paul Link to comment Share on other sites More sharing options...
Silver 21 Posted June 5, 2002 Share Posted June 5, 2002 As Mark has highlighted earlier I line up the front of the nosecone with the front edge of the deck on my minno (I have a block that sits between the front wheel and the edge of the neck). I used to tow with the front wheels up to the front edge but the balance was wrong, once you've fouund the right place your trailer sway will be solved as long as you don't drive too fast especially downhill!!! Towcar: Seat Alhambra 115bhp Turbo Diesel/6 speed box!! Graham cool.gif1700 Live Axle X/Flow, got the engine upgrade, got the new tyres, now got to lose some weight [red]cool.gif id=red> Link to comment Share on other sites More sharing options...
Mark Durrant Posted June 5, 2002 Share Posted June 5, 2002 Also avoid overloading the boot of the car as this will lift the front giving less grip, very dangerous in the wet, especially with front wheel drive. In addition I always tow with a stabliser which dampens down any snaking of the trailer. Money well spent in my book. Link to comment Share on other sites More sharing options...
John Howe Posted June 5, 2002 Share Posted June 5, 2002 Having spent 35 years, plus, towing all sorts, from, hay, straw, horses, cattle, sheep... to what ever. Is your trailer single or twin axles... if the former, (IMHO) buy a new trailer or drive slower! If twin axle, do not let the weight balance on the trailer lift the rear end of the tow vehicle but rather increase the weight to the drive wheels on the trator unit. In the USA they have wonderful pickups and swan neck trailers, were all of the weight is balanced on the tow vehiles drive wheels... excellent results in terms of wheel grip. JH Link to comment Share on other sites More sharing options...
stevefoster Posted June 5, 2002 Share Posted June 5, 2002 Does the above apply to front wheel drive cars...? The bigger and heavier the tow vehicle the less critical the weight dist becomes. What might be fine for a big heavy Passat or Disco won't be ok for my pathetic (but it gets me there) ZX. Edited by - stevefoster on 5 Jun 2002 15:55:07 Link to comment Share on other sites More sharing options...
John Howe Posted June 5, 2002 Share Posted June 5, 2002 The law states and has produced a table of tow vehicle weights and the allowed weight of laden trailer they may tow. Start backwards, what does the car plus trailer weigh... is the car heavy enough to tow it. The tow vehicle's weight is more important than its engine power... assuming it has the power to tow! JH Link to comment Share on other sites More sharing options...
John Howe Posted June 5, 2002 Share Posted June 5, 2002 The law states and has produced a table of tow vehicle weights and the allowed weight of laden trailer they may tow. Start backwards, what does the car plus trailer weigh... is the car heavy enough to tow it. The tow vehicle's weight is more important than its engine power... assuming it has the power to tow! JH Link to comment Share on other sites More sharing options...
bl0498 Posted June 5, 2002 Share Posted June 5, 2002 John, A Minno is a very small 4 wheel braked trailer weighing approx 375kg - so with a 550kg Caterham the all up towed weight is about 925kg. An Audi 80 will be well into 1.4 tonnes I would guess. Like Mr Butty (hello Graham) and F355 I have found that the most stable position behind my Saab 9-5 estate/900 hatch is to line the front edge of the nosecone with the front cross member of the Minno. Works a treat - but any rig will feel much more unstable going downhill. Ian - the boys in blue particularly watch out for trailers in the outside lane on motorways too! Brian Link to comment Share on other sites More sharing options...
Nifty Posted June 5, 2002 Share Posted June 5, 2002 Most likely due to previous weight issues. Other points to note:- Is your towball greased? A lack of grease can cause the trailer to swing from side to side as the friction causes a small torsional build up and then release, causing over movement and a repeat process coming back. Hence a build up to an equilibrium quantity. I am assuming the trailer is not twisted at all and therefore crabbingquestion.gif. The worse case of trailer swinging will be caused by excessive weight on the towball causing weight transfer from the steering wheels. Any undulation will cause the front wheels to momentarily leave the road surface whilst more often than not simultaneously causing the trailer to move away from straight ahead and thus swinging the vehicle around a pivot of the back axle. This can lead to a very serious accident in a matter of seconds due to a natural tendency to throw bags of opposite lock on which then suddenly bites and throws the vehicle the reverse way, weight transfer exaggerating this and so on....BANG!! Too much weight at the back lifting the rear towing vehicle wheels will obviously cause reduced traction for rear wheel drives. More importantly it reduces the braking effect of the trailer hitch brake and will cause the vehicle to jack-knife under breaking as the trailer pushes the vehicle(further lifting the rear). Nifty. Edited by - Nifty on 5 Jun 2002 21:09:30 Link to comment Share on other sites More sharing options...
Ian Barkley Posted June 6, 2002 Author Share Posted June 6, 2002 Thanks for all the suggestions and information, I've moved the weight forward a little and it seems more stable, and I will watch the speed... Thanks Ian Link to comment Share on other sites More sharing options...
stevefoster Posted June 6, 2002 Share Posted June 6, 2002 My ZX can tow 1100 kgs according to the manual. This is to do with hillstarts fully laden. The rule of thumb is 85% towed weight of car weight for comfortable towing. I am ok with this using a Minno. I borrowed a Brian James A series, these are heavier and it was very stable with 60 kgs nose weight but took a lot more lugging about than the Minno! Edited by - stevefoster on 6 Jun 2002 10:40:40 Link to comment Share on other sites More sharing options...
Fun to Drive Posted June 6, 2002 Share Posted June 6, 2002 First port of call has got to be the vehicle and trailer manufacturer. They should be able to offer advice on correct loading condition. Some good comments on loading, nose load and inertia. In my experience (some bad) these are hugely important. In general though nose-load is crucial. The best nose load will reduce the tendency to swaying, and improve the cornering behaviour. In general there is a trade-off between swaying and 'oversteer'. If the rig is swaying try increasing the noseload, and make sure the rig behaves o.k. when cornering. From experience, the best nose load tends to be between 5% and 10% of the trailer load, 7% is usually the best starting point. Nose load can be very important with twin axle trailers. Large loads at either end of the trailer will have less effect on the cornering behaviour than the swaying, large loads will make the rig more unstable. Haynes do a good basic book on towing. Or maybe call to a caravan centre. We may hate caravan owners at times but they may give you invaluable advice, especially in respect of friction dampers, measuring nose load. Keep the revs up Link to comment Share on other sites More sharing options...
tic Posted June 6, 2002 Share Posted June 6, 2002 Did I say 50 lbs .... oops ... meant Kgs :-) slightly important ! Cheers Link to comment Share on other sites More sharing options...
stevefoster Posted June 6, 2002 Share Posted June 6, 2002 That's more like it tic! Steve My racing pics hereid=red> Hants (North) and Berkshire area club site hereid=red> Link to comment Share on other sites More sharing options...
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