Motorhome Magazine Dinghy Towing Guide

Getting Your Dinghy on the Road Without a Headache

I've spent roughly a decade lashing cars to tow-behinds and figuring out why they don't rattle themselves apart every time you hit a pothole. The Motorhome Magazine Dinghy Towing Guide covers the basics well enough — flat-towing, base plates, tow bars, brake systems — but the real world has a way of complicating things the article doesn't always address. Here's what actually matters when you're setting this up. The guide breaks down the legal and mechanical requirements clearly: your motorhome's plate weight, your dinghy's kerb weight, whether your car can be flat-towed or needs a trailer, and the mandatory braking equipment. It also runs through some popular base plate kits and tow bar combinations. Useful starting point. Not the whole picture though. The legal bit in the UK is straightforward after the 2015 updates. You can flat-tow a vehicle up to 750kg over the motorhome's unladen weight, or up to 85% of the car's kerb weight — whichever is lower — without requiring the car to have its own brakes. Above that, you need a separate braking system on the dinghy that can be activated from the cab. That's usually an electro-pneumatic unit like a Stop Tech or Al-Ko unit. It's fiddly to fit but not rocket science.

One thing most people get wrong is the maximum towing speed. The Motorhome Magazine Dinghy Towing Guide mentions it, but it bears repeating: many base plate kits and tow bars are rated to 60 mph, not 70. If you're doing motorway miles regularly at higher speeds, check your specific kit's rating. I learned this after one of those quiet, expensive moments where you glance in the mirror and notice your tow bar arm is oscillating like it's trying to escape the mounting points.

The Setup: What Nobody Tells You

Base plate selection comes down to two things: ground clearance and frame access. Some cars, particularly the newer ones with complex front-end aerodynamics and sensor pods, make base plate mounting a nightmare. I spent an afternoon last year working on a Ford Kuga where the crash box had to be partially removed just to get the lower mounting brackets seated. The base plate kit was supposedly universal for the model range, but "universal" in this industry usually means "it fits if you're willing to compromise." The tow bar itself is simpler. A swivelling tow ball is worth the extra money — it lets you back into tight spots without twisting your car into a geometry that makes sense only in a third dimension. Non-swivel bars work fine on straight routes, but the day you need to reverse into a narrow layby to let an oncoming vehicle pass, you'll wish you'd spent the difference. Brake controllers need to be mounted so you can see them and reach them without contorting. Most people install theirs on the dashboard near the windscreen. Fine. But if you're tall and your steering wheel adjusts, make sure your viewing angle still works when the wheel is lowered for comfort driving. I've seen owners completely blind to their brake controller's status because they repositioned their seating and never reconsidered the mount.

Common Pitfalls and the Things That Go Wrong

The most common problem I see is people towing cars that shouldn't be flat-towed. Not all four-wheel-drive vehicles can go on all four wheels. Some part-time 4WDs will destroy their transfer cases if driven with the front wheels rolling. The Motorhome Magazine Dinghy Towing Guide touches on this but it bears repeating: check your vehicle's handbook before anything else. If it says "transmission in neutral" and doesn't mention a specific procedure for flat-towing, it probably can't be done without modification. Another issue is the auxiliary battery. Most brake controllers draw power from the car's electrics. If your dinghy is going to sit for weeks at a time while the motorhome is in use, the auxiliary lead will drain the car battery flat. A simple solenoid relay or a dedicated leisure battery wired to the tow bar connector solves this. It adds about £40 to the bill and saves you from jump-starting your dinghy every time you want to move it. Tire pressure matters more than people think. A dinghy tire at the wrong pressure doesn't just wear unevenly — it changes the tracking behavior of the whole setup. I once spent thirty minutes adjusting tow bar tension on a Vauxhall Astra before realizing the left-rear tire was 8 psi under spec. The car was pulling to that side and no amount of spring adjustment was going to fix it. Check pressures when the tires are cold and recheck after the first few miles of towing.

Weight Distribution and Synchronisation

Unladen weight distribution on the tow bar matters. If your motorhome is lightly loaded and the dinghy is near its maximum allowed weight, you'll get tail-heavy behavior on the motorhome itself. This affects steering response and braking. The sweet spot is usually around 50-55 kg on the tow ball, give or take depending on your motorhome's design. Too light and the tow bar bounces. Too heavy and your front axle becomes underweighted. Synchronisation between the motorhome and dinghy brakes is something the cheaper brake controllers handle poorly. When you apply the motorhome brakes, the dinghy should respond within milliseconds. Older electro-mechanical systems can lag by 0.3 to 0.5 seconds, which at 60 mph means the car is pushing the motorhome for a meaningful distance before its own brakes engage. Modern proportional controllers are better but still not perfect. A brief test in a safe, empty car park after installation is absolutely worth the ten minutes it takes.

What the Guide Gets Wrong or Misses

The guide is thorough but it assumes you're working in ideal conditions. In practice, mounting points on older cars can be corroded to the point where they need reinforcement or replacement. I've stripped threads on BMW front subframes that looked fine until I actually applied torque. Using a threadlocker on every base plate bolt is non-negotiable. The guide mentions this but the emphasis isn't strong enough. Another gap is the question of insurance. Many policies require you to declare the dinghy as part of the motorhome setup rather than as a separate towed vehicle. If you don't, you may find yourself with a claim that's partially or entirely rejected. Call your insurer before you buy the kit. It takes five minutes and prevents a very unpleasant surprise later. The guide also doesn't discuss what happens when you need to drive the dinghy separately from the motorhome. If the tow bar is fitted, you can't just unhitch and drive away — the tow ball stays on the car. Some people fit removable tow balls, which solve this but add another failure point. It's a trade-off you need to think about based on how often you'll actually separate the two vehicles.

Practical Checklist Before You Hit the Road

Verify your motorhome's maximum authorisable mass and your actual laden weight. Check that the combined weights don't exceed the tow bar and base plate ratings. Inspect the wiring connections — corroded contacts are the most common cause of brake controller failures. Test the lights: brake, indicator, running, and horn if applicable. Make sure the dinghy's steering lock is disengaged and the ignition is in the correct position for towing. Check the tow bar arms are secured and the safety chains are crossed under the tow ball. Verify tire pressures on both vehicles. Confirm your brake controller is charged and responding correctly. Write down your setup weights and keep them in the motorhome so you can reference them at the border or if asked by enforcement. Dinghy towing is one of those things that seems simple until you're on a B-road in the rain and the car behind you is tracking slightly left. The Motorhome Magazine Dinghy Towing Guide will get you 90% there. The other 10% comes from experience, patience, and not skipping the tests.