Offroad trailer drawbar length?

This is an interesting question.....when you look at some of the dearer offroad campers the distance from the hitch to the axle is long to say the least and certainly not balanced it seems.

I have been going to measure a few at the 4x4 show and enquire about the legal aspect and load/ balance issues however it does not seem to effect towing performance.

Just don't try to pick it up...lol
But they pack a bit on them.

Hi Crackles,
ADR 43/30 covers it I think.
http://www.comlaw.gov.au/ComLaw/Legislation/LegislativeInstrument1.nsf/0/043FB838C0BD224FCA2571640013091C/$file/ADR+43-04+%5BFINAL+FRLI%5D.doc
I find the longer the drawbar the easier generally to back as it doesn't react as quick.

Rgds

There is also another consideration. The length of the drawbar affects how the trailer tracks behind your vehicle. in other words how it follows your vehicle wheel tracks.

Don't know how it's calculated butthere must be a formula somewhere.
Below is an extract from this site

http://www.expeditionswest.com/equipment/adventure_equip/Jumping_jack.html

For the trailer to track inside the path of the tow vehicle, the coupler to axle hub distance should not exceed the tow vehicle wheelbase. The only real trail restrictions would be as a result of its size (mostly related to the 91" width).

Gem of a subject. However, I reckon the questions you should be asking are 'ramp-over' angle and 'rear departure' angle i.e. account for clearance / underbody features also. Applicable to trailers as well to 4wd's. Ultimate campers are only manufacturer (to my knowledge) that state these. Some drawbars are so long and it would have to affect ramp-over as well as hitch load a great deal. One subtle factor in ramp over is hitch mounting height - we've mounted ours as high as we can without stopping rear doors fom opening (got about 10mm clearance!!). Obviously wheel / tyre size can have a large affect as well. Cheers JD

..good topic, I just happened to look up 'www.Alibaba.com'

http://www.alibaba.com/product-gs/206238847/OFF_ROAD_trailer.html

..dead scary pricing, the whole trailer kit, tent, etc., $US 1100-1300, min order 25 units. Check the details.

Just ran the tape measure over my 04 Campomatic Hard floor (flip over) camper (ind coil, suspension). The actual box is 2300mm long (not including the rear swing away spare wheel). The road wheel centreline is 1100mm from the BACK of the box. The drawbar reaches to 2050mm from the front of the box (tip of the hitch). This trailer has a wedge shaped storage box on the drawbar, to accommodate tight turns. Been good for us to date - has seen plenty of twisty turning bush travel and creek beds etc.
With the 120L water tank full (underside - right at the back) the 'ball-weight" is about 90kg.

I tow a few trailers.
No 1 has a short drawbar of 1200mm.
Tows OK but a b*gger to reverse.
No 2 - My box trailer is 1500 long and not bad. Good compromise.
The CT is a 2m draw bar and tracks well, but can still jack knife it.

For clearance over humps the CT is as good as the others, if not best as it has a higher hitch.

All have 15" or 16" wheels for clearance.

Go the 2m, more space on the draw bar to mount stuff, like spare wheel and tool box.

Craig, a few of the Kimberley Karavan owners are fitting drawbars extended but over 400mm from standard. We reckon we get better control and better balance on the towbar. Of course it can lesten the weight applied to the back of the car. Will measure it up tomorrow. It has been up in the HC to no particular disadvantage.

Has anyone looked at a fairly short drawbar setup, within reason, still with room for a box or what ever on it. But, to make backing easier make the A frame with an extendable middle beam that can be pulled out to give greater manoverability when reversing or for more stability at speed?
Just a thought I had awhile ago after folding my little rubbish trailer under the back of the ute... :(

Just measured mine..(trailer that is)...

From axle to pin of Treg hitch = 2700mm
From front of 'box' to pin of hitch=1590mm
From axle to rear of box=900mm

Gday Craig,
I asked a similar question a few months ago. I have a H/D offroad box trailer, the box is 6' x 6' with internal guard with the draw bar being 1000 mm from the front of the box. I find that with the short drawbar,the trailer waddles behind, especially on dirt roads at speed. Also getting to the barn doors on the Patrol is difficult. I have decided to make a telescoping single bar and have it adjustable at 1200mm and 2200 metres. I have all the metal tubes and bit fabricated and i was hoping to have it complete before Innamincka next month but i have just ran out of time to put it together. So the short, although a little longer than in have now will be good for tight tracks and i can stretch it out for the highway.. I hope i can complete by Xmas.. Michael

My new home built one appears to be working out fine Craig.

Its essentially a 2.4m by 1900mm wide flat box with a 1300mm from tow ball to front of box.

This makes it 2500mm from tow ball to axle but this increases by 50mm as suspension takes up under load.

This allows it to carry 3 bikes with bolt on channels , and these can be removed and other top deck arrangements used in future.

Finished weight was $300kg of which 104kg is in the 3 235/85/16
Patrol wheels.

Just looking at it you would think the axle is to far back but it balances very well with 15kg down thrust unloaded onto the front jockey wheel.

We thought about it a lot and ended up putting the spare wheel underneath and just behind the axle.

We have throughly checked its clearances in use and it seems to be fine, we can almost put trailer at right angles to the car.

Handles bumps well after fitting some new shock bump stops.

The trailer coupling can be attached to the car in 4 different ways by mounting above and below the cars tongue.