To the teeming millions of well informed dopers, I need some help please.
I am investigating starting a new business venture that involves marketing, selling and renting tandem axel personal car trailers. (the sort that you tow behind your car / truck to take your car to track etc)
Without going into too many details at this stage on exactly what I am doing (I don’t want anyone to steal my idea) I would like your opinions on some background information. In addition to this I will, of course be doing my own research.
For the purposes of discussion, I do know cars in a general sense, I read and enjoy them, I have driven with trailers (but not braked car trailers) in the past, but I have no mechanical skills or engineering knowledge whatsoever. I guess you would say that I am better informed than average, but my knowedge doesn’t rise to that of a true enthusiast.
What can you tell me about tow ratings?
Braked vs unbraked trailers - any differences in handling?(besides the obvious that braked have their own brakes :p)
I am not in the US, if mylocal police required some sort of “certification” that somebody was competent to drive with a trailer, what sort of tests would you recommend?
What challenges would I face in loading cars onto the trailer?
Cars must obviously be tied down - is this easily handled for exoitcs? (Maserati, Ferrari etc)
Accident safety for these sorts of trailers?
Accident safety for rear end collisions for cars with tow balls - does this have an impact (heh) on the car that hits me from behind in terms of safety. (I know not that much difference to my safety - what about his) when I am NOT towing a trailer
How hard is it to rig the tow hitch so that it is removable and doesn’t protrude beyond the rear bumper.
Well I guess that is a lotta questions, and Tuckerfan, if your are around perhaps you would like to recommend a good motorsport discussion board where I may be able to follow up some of these questions?
A receiver-type hitch has (with the square hole in thesephotos) usually doesn’t protrude past the bumper. The ball assembly is secured into the square hole and is removable.
ETA: The receiver itself is not readily removable.
I did a cross-country move about 13 years ago. I rented a truck from Ryder, and a trailer to haul my MGB. Some recollections from that trip:
Loading the car wasn’t bad. I lived on a hill, so I had to find a level spot about a block away. The tiedowns were easy, if I remember correctly there were hooks that went over the axles, and a rachet system to tension the chains. If the Lamborghini owners don’t want to risk scratching their axles, there might be a way to stretch a net over the tires and attach that to the floor of the trailer. The ramps to drive up on the trailer were kinda heavy, but manageable. Of course, that trailer had to be designed to handle any kind of car. If you’re selling or doing longer-term rentals, you might be able to customize them.
Driving the truck with the trailer was so easy I almost forgot it was back there. But that was a heavy truck and a light car. People told me that it handles best with 10% of the trailer weight on the hitch, and the other 90% on the wheels. Maybe I got it just right. There was a mark on the trailer for where the car’s center-of-gravity was supposed to be.
Don’t forget the connection for the lights on the trailer; brakes, turn signals, etc. We had a boat when I was a kid, and I remember it gave my dad fits trying to get that all working right. Maybe it’s a standard connector now.
I also remember my dad talking about the trailer brakes. The master cylinder was built into the trailer itself, so that when the car slowed down the momentum of the trailer pushing against the hitch compressed the cylinder and applied the brakes automatically. But, if you want to back up, uphill, to park the trailer, you’re fighting the brakes as you do it.
I don’t know if that addresses any of your specific questions, but I hope it helps. With no training or practice I was able to load a car, haul it 3,000 miles, and unload it with no problems.
To Gary - good point - I forget about the removable ball. To Robot, yeah the MGB is a really small and light car, I hear you though about the C-G, that is something for me to bear in mind when I am talking to the trailer manufacturer.
Yes I am in contact with one (trailer manufacturer), and it will be generic - I am being very careful abt my size at the moment. I expect that if I get approval for this, part of the process will be some sort of special cert for the driver (trailers like this currently aren’t allowed here).
Hmmm…interesting point about the brakes being activated by pressure on the ball…anybody got more info abt that? I always thought / assumed it would be done via wiring somehow through the plug that puts the car signals back to the trailer.
BTW - the lighting / signal plugs are (or at least were) one of two generic types, so that is not such an issue now I don’t think. I have had them installed to my cars before and am used to using them.
On the business side: these sorts of rental trailers are very common in the US. They are much more often rented for moving house across the country than for taking a race car to a track or an exotic to a show. The folks who do that do it often enough to own their own trailer.
The value of the rental proposition for the person moving is that they can rent it here & turn it in there. IOW, the business model only works after you’ve got multiple locations in multiple cities.
On the technical side: There is also the half-trailer, which is a just cradle for the front wheels of the towed vehicle. The towed vehicle rolls on its own rear wheels. The advantage is easier loading & much cheaper.
These guys Your moving and storage resource | U-Haul are the leading US outfit, with about 15,000 locations. There’s nothing they don’t know about towing or the rental business. You may be able to learn a few things poking about on their website.
What are you planning on using for a tow vehicle? It sounds like you want to tow a car hauler with a car? That just isn’t going to happen. You’ll need a heavy duty truck to haul that much weight.
If you are planning on just towing the empty trailer with a car - maybe. But, not with a car loaded on it.
Ok - I really don’t want to go into specifics here, because it is still just an idea that I am gathering background information on to see if it is viable (and I don’t want my idea stolen) BUT
These sorts of trailers are not currently legal here - so **nobody **has one
There are no race tracks here, so I have different things in mind than hauling a car to track
Thaks for the link to uhaul though - its appreciated
Hmmm… I have seen them hauled by midsized pickups and large sedans. But this is part two of my research, that I don’t need to do here - it is being done via manufacturer websites to get tow ratings on specifics models of cars, so thanks for the thought (I have contacted a trailer manufacturer who advises that the trailer is about 600 kg, meaning my tow car needs a tow rating of 2600 kg for a 2 tonne car)
Dude - thanks a million for this, anecdotal information like this is invaluable in giving specs to the trialer manu, and seeing if this is really viable. THe sort of truck seen here is what is being used now, I am trying to see if there is a cheaper and faster option for people that want to get their cars from one place to another.
Again, what are you planning on using for a tow vehicle? My Jeep Cherokee has a tow rating of 5000lbs (2300KG) and that’s with a tow package. Thats a 200 HP engine, 225 FtLbs of torque and a beefy suspension system. I wouldn’t pull a car hauler more than a few blocks with it.
The hydraulic brakes that are activated by the trailer pushing into the tow vehicle are called surge brakes. They’re OK for short term, lightweight use, but the preferred system is electric brakes managed by a brake controller that’s wired into the tow vehicle. More and more larger pickups have controllers built in at the factory. Otherwise, vehicles that are built with towing in mind will have a plug under the dash to connect the controller to.
You might be able to get away with surge brakes for trailering a very lightweight car, but having towed things with surge brakes and with electric brakes, the electrics are far better. One thing you can do with electrics is to push a button on the controller to slow down only the trailer - immensely useful if the trailer starts fishtailing. It’s impossible to do that with surge brakes. And, as mentioned earlier, you may wind up fighting surge brakes when backing up.
On wiring - yes, there are several types of plugs out there. Around here, everyone seems to have settled on a 4-pin design for light trailers with no brakes and what’s called a 7-blade plug for larger trailers and RVs with electric brakes. Once in a while, you’ll run into 6-blade plugs, but they’re pretty uncommon. Some tow vehicles are being built with both the 4-pin and 7-blade connectors, and are ready to tow almost anything.
Look up hitch receiver “classes” - these are broad categories of how much weight can be safely pulled and controlled, ranging from the itty-bitty Class 1 that clamps onto a bumper and can handle the weight of a couple bicycles on up to Class 4 weight-distributing hitches that are part of the vehicle’s frame and effectively transform the trailer into an extension of the tow vehicle, rather than a heavy lump to be dragged behind. For a car trailer, Class 3 is probably what you want to shoot for.
that I don’t need to do here - it is being done via manufacturer websites to get tow ratings on specifics models of cars, so thanks for the thought 
