OFF-ROAD trailer construction has always been a compromise between providing enough rigidity to handle the extra-rough terrain and enough travel in the suspension to prevent damaging the boat.
Ruhle Trailers in Brisbane was presented with exactly this challenge about four years ago by a fishing guide working out of Darwin. His 17-foot aluminium boat was spending more time in the workshop being repaired than it seemed to spend on the water. The damage was being done on the road, not the water, and the over-rigid trailer suspension was the root of the problem.
Alex Duff and Peter Ruhle, the men behind Ruhle Trailers, rose to the challenge and modified an existing suspension system. Their new system offers a much smoother ride than the traditional leaf suspension system used on boat trailers. Not only did their suspension offer a smoother ride but, because of the way it is mounted, it increased the clearance – which is another problem in really rough terrain.
The unique system involves a square torsion bar mounted inside a box section, with four rubber mounts filling the corners of the box section between the wall and the torsion bar. Called the Rubber Torsion Bar Suspension System, this fully galvanized design offers a far smoother ride but also independent suspension. After four years and 50,000km on Northern Territory roads, many of which were dirt corrugations, neither the boat nor trailer have had any repairs other than general maintenance.
Quay Marine in Cairns heard about the new suspension and worked in conjunction with Ruhle Trailers to develop a specialist off-road trailer suited to conditions in the Cape and Gulf, where many north Queensland fishos travel.
The trailer, which is available through Quay Marine, has a number of unique features which include:
Mesh walkway (or ‘toe saver’ as it's called in croc country);
Swing extension drawbar for beach or steep bank launching;
Checker-plate mudguards, with fill-ins to prevent stone damage;
Off-road poly block coupling;
Choice of wheels - 205 R 16 alloys as standard;
Heavy-duty winch post;
Heavy-duty swing away jockey wheel;
Rubber suspension - fully galvanized; and
NSK bearings as standard.
The off-road poly block coupling allows maximum range of movement for negotiating the likes of steep creek crossings without the worry of the coupling popping, which can be a problem with standard ball and socket couplings.
The swing extension drawbar is a cinch to use. You just remove the lock pin, swing the draw bar around to the front and use the same pin to lock it in position again. The off-road poly block coupling on the end of the extension bar allows maximum movement, and the tilt draw bar allows even more flexibility in launching and retrieving in those really hard-to-get-at situations.
The mesh walkway gives you more confidence when guiding the boat on and off the trailer, making it that bit harder for a flat dog to take a snap at you.
The fill-ins on the checker plate mudguards reduce stone damage, while the checker plate makes them safer to walk on when wet, as well as being structurally stronger than standard guards.
The swing-away jockey wheel means one less thing to be stowed away or lost in transit.
Not satisfied with the results of just one trial, Peter Ruhle has run four more trials, two using rubber suspension and another two using an off-road shackle spring system. Peter described all trials as “a resounding success”.
An extensive search for a suitable off-road leaf spring eventually came up trumps, with a longer and wider leaf used than on standard boat trailers. The reason for searching for alternatives to the Rubber Torsion System was to accommodate those who prefer to stick to conventional suspension systems.
Other options available for Ruhle off-road trailers include:
Spare wheel and carrier;
Choice of lights from the standard types to the new Hella LEDs;
U-Bolt mounts for bracket and roller mounts to prevent movement;
Off-road shackle springs and axle galvanised; and
Spare spring and frame mounted spring carrier.
The Ruhle off-road trailer is sure to find plenty of takers in the north, as well as those more adventurous souls in the south-east corner. For more information contact Ruhle Trailers on (07) 3376 8200 or Quay Marine on (07) 4041 3166.
1) Profile of a Ruhle off-road trailer showing mesh walkway and checker plate mudguards, with fill-ins.
2) The offset mounting of the Rubber Torsion Bar Suspension provides increased ground clearance.
3) The off-road poly block coupling.
4) The swing extension drawbar is pinned to the A frame for easy access.
5) The swing extension drawbar locked in position ready to use.