Towbar vs roof carriers on modern cars?

I've got a modern-ish car (2017) and it knows when the towbar rack is attached and switches off the rear parking sensors.  I've got a detachable towbar but when I've left it in place without the rack it doesn't seem to affect the sensors, but if you had one right in front of the tow bar I presume it would.

I was torn on this for a while too and ended up going towbar.

For me, the largest part was how easy it is to remove the rack when not driving to riding spots, as bike theft is rampant here in Bristol.

Also, they seem to suit long wheelbase bikes a little better, whilst someone will probably post below that you can get an XL geometron on a roof rack, they sit more comfortably on my thule easyride tow-rack than friend's roof racks.

Slightly better mpg/less noise too, though for me the above two were the largest concerns.

I would always go manufacturer bars with a car. The feet are made to only fit that model, rather than some generic fitting to suit a dozen cars like Thule. Both work, but if you want the bars off between uses, manuf are best in my opinion

Do you need 4 bikes on the back or could you just load 3 onto a boot rack (saris bones etc) and throw the last one in the boot/seasucker it to the roof? Not a great solution for regular use but saving £800 seems like a good shout

I generally liked my roof mounted carrier but eventually got a bigger car so I could fit my bike inside.

What I didn't like:
1. Muddy water on the roof and windscreen unless you wash and rinse your bike very well
2. Height barrier anxiety
3. Fuel consumption increase was probably around 25%
4. Leaving carrier on the rack at home is a sign for "there are bikes in the garage"
5. Stands out in traffic - would be easy to follow someone home
6. Hate seeing how much it flexes and wobbles on corners and speed bumps (even at slow speed). I don't see my own, just followed other people and know mine must be doing the same.
7. Fear of messing up lifting a heavy wet bike onto a high roof (as a shortish person) and dropping it, damaging the car

If you can swallow the expense, tow bar bike rack is the way to go, plus once you have a tow bar it opens up the option for towing other accessories…

700-900 is expensive - had mine recently fitted for £550. Where are you based?

Find a cheaper towbar fitter.

Much easier and quicker loading and unloading, quicker to mount then roofbars, more mpg's, no forget the low car park barrier etc etc.

I would always go manufacturer bars with a car. The feet are made to only fit that model, rather than some generic fitting to suit a dozen cars like Thule.

To do know that Thule make half the manufacturer own brand bars and feet etc? Mine say Volvo on one lot and VW on the other, and I used to have Halfords Advanced racks - all were rebadged Thule.

Previous car couldn’t have a tow bar so had roof bars for a few years. Went back to tow bar the moment I could on the new car.

Suspect you’ll make back the extra cost in fuel fairly quickly.

Towbar is my preference. Current car doesn’t have one and I can’t have one fitted and have had to the roof at route. Have to use a folding step to get the middle mounted ones on/off safely.

The reversing sensors should cut out when the rear bike rack is connected. But yeah tow bar every time. There is a good fitter near you. I will pm you details.

We switched to a roof carrier when we bought a caravan as you can't tow while using a towbar one.

Much prefer a towbar one, you can see the bikes, it's easier to load, clean roof, better mpg, and you don't drive around with a roof rack permanently fitted.

£450 seems cheap for a rack & Thule bike carriers, last time I looked Thule bike carriers alone were over £150 each.

An independent towbar fitter will be significantly cheaper than a dealer.

Also, when you get an ebike (IMO, we'll all sooner or later), you'll need a towbar rack for the weight, so if you keep cars long term that might be a consideration.

Cheers all. Confirms my initial leaning towards the towbar.

Had a few cars that couldn’t take a tow bar and hat to resort to roof racks. Only good thing is you can leave roof racks on the car if using regularly, in every other way a tow bar is a better option.

Takes me 30 seconds to to fit the detachable tow bar and rack, bikes are rock solid when mounted, options to lock bikes to chassis/tow bar, no mud/chance of damaging roof, no worries with low barriers etc. Best option other than a van imo.

Also - check out second hand offerings.
There's a good selection of Thule available at a lot less than new at any given time.

@ceept how comes you didn't just stick the bikes in the caravan? Often see cars towing a caravan with bikes on a roof rack. I assume I'm missing something obvious.

We've had both options fitted to different Octavia estates over the years.

Roof bars:

only minor change in fuel consumption, less than 10%.

We left ours on the car all the time, so easy to just take a couple of bikes.

Height barrier anxiety is a thing

Reaching across to fit 4 bikes was a struggle for me at 5'9, needed to carry a little step stool

Tow bar:

Got a detachable tow bar for the current car, with Atera Strada rack, so all removed when not required.

Rear sensors deactivate when the rack is plugged in to the socket.

Easier to get bikes on and off.

If its just me, bike goes in the boot anyway.

Towbar rack makes a great bike stand when we've been camping etc, with appropriate locks

After 20 odd years of using roof bars, we got a towbar rack for our Alhambra as Mrs FB couldn’t load a bike on its roof.
We already had a towbar fitted so just had to get the bike rack. I’m a convert to towbar racks now.
Only downside, it used to be easy spotting the cars in car parks when they had roof racks on.

I've always used roof-bars, and always have the racks that mount using the forks (remove the front wheel). I think with these options, you pays your money and makes your choice, both roof and tow hitch systems these days are pretty reliable, both have pros and cons, both effect fuel consumption to a greater or lesser extent.

As far as I’m aware, a detachable ball version means no issues with the parking sensors etc. (Though I don’t know how they behave when the rack is fitted—presumably either they electrically detect the lighting board and switch off, or they constantly go crazy.)

Many modern cars require dedicated wiring and software updates in the car, don't assume it'll be plain sailing.

My OH's car even though it was bought new with a manufacturer supplied and dealer fit towbar doesn't turn off the rear parking sensors when she's her horse trailer attached - so she's to switch them off, which switches off the fronts too...

My car needed 'coding', so I paid a bit extra so it used the BMW loom, but did get it done by a local specialist - trouble is now that when it went in for a recall at BMW they couldn't update the emissions software as the car wasn't supplied with a towbar from the factory.  It does though auto switch off the rear sensors and fully integrate it to all the electrics etc.

And there's always someone who only spent £x on a towbar, and then you find out it's on an old car etc.

@jeffl

Caravans are build really light, and fragile. The payload on our 6-berth is only about 170Kg. If we carried them inside, we'd use a chunk of that, any they's smash the inside. I don't want to think about cleaning after having muddy bikes in it.

Also, they can stay on the roof when we are driving back & forward to trails, or just stopping overnight.

i bought some cheap used roof racks for the wifes berlingo.

But for my car - no one puts roof racks on them(other than those stupid baskets you see on "Scene" cars) so it was mega expensive to buy new.

Tow bars - don't exist.

so given its occasional use i went with a suction cup model ease of fitting and removal cannot be faulted and the tiny bit of space it takes up is amazing compared to a full roof rack or even tow bar rack.

and the cost is less than rack + tow bar or roof bars plus bike racks.

downside is its bike specific

700-900 is expensive – had mine recently fitted for £550. Where are you based?

I looked into this recently for my astra (2015). In the end i bought the whole kit from https://www.just-tow.co.uk/ for £250 and fitted it myself. it wasn't that bad to be honest. As it's a canbus it only required a couple of wires

I'd be more worried about putting an expensive bike on a roof where I can't see it, than having a problem with reverse parking for a few seconds.

It is possible to use a towbar bike rack and still tow a trailer/caravan. You get a two-bolt towbar fitted, plus a rack that clamps with a flat, upright plate between the towball and the towbar.  Witter produce this sort of rack and it's both cheap and cheerful.  You'd still need a separate light board, of course and something to strap the bikes on with.

Personally?  1 bike goes inside the Superb.  For two, towbar and a dedicated Thule compact rack. I'm really not keen on bikes on the roof and haven't done that for many years.  They always seem awfy wobbly and more bikes = more fuel.

I looked into this recently for my astra (2015). In the end i bought the whole kit from https://www.just-tow.co.uk/ for £250 and fitted it myself. it wasn’t that bad to be honest. As it’s a canbus it only required a couple of wires

This what intheborders was alluding to above. Mine would be £420 from there, but then you see "coding required". Would be interesting to see how easy/expensive it would be to get it coded when you've bought all the kit from elsewhere.

My OH’s car even though it was bought new with a manufacturer supplied and dealer fit towbar doesn’t turn off the rear parking sensors when she’s her horse trailer attached – so she’s to switch them off, which switches off the fronts too…

thats pretty poor. On vauxhalls, the sensors are turned off if the lighting board is plugged in, but even if it isnt (as on a thule xpress rack) - it still senses something is 0cm behind you as you drive forwards, decides its something on the back and disables the rear sensors for you

Downside I found with towbar rack was the bikes getting covered in road grime, especially during winter with gritted/salted roads up here. Could've been coincidental but the years I used a towbar rack were the time I had worst issues with bike disc brakes.

Roofbars are my preference. Manufacturer-specific as mentioned above as first choice, then Thule. Even better if the car has some sort of fixpoint where the roofbars bolt directly to the car with zero paintwork touching (BMWs and VWs often have this).

Downside I found with towbar rack was the bikes getting covered in road grime, especially during winter with gritted/salted roads up here. Could’ve been coincidental but the years I used a towbar rack were the time I had worst issues with bike disc brakes.

easily solved with some rotor covers, or a shower cap if you're classy

expensive bike on a roof where I can’t see it

Panoramic roof ftw!

Our Alhambra is a 19 plate- no problems fitting the bar a couple of years after getting it and sensors & camera automatically turn off when the light board is plugged in as per comments above.

One thing to consider is how long you want to keep a car. If you're a serial changer it'll add up getting towbars to each new vehicle. At least with roof bars like Thule you can change the fitting kit/footpack.  I've had bars that are long enough to fit over several cars I've had.

how comes you didn’t just stick the bikes in the caravan?

Yeah I've done this, it trashes the inside very quickly. They bounce around a lot, having very crude suspension generally.

The Swift Basecamp has a hard floor and lashing points for your bike, I think - and the whole back opens to get them in and out, but that's a very specific caravan.

I’d be more worried about putting an expensive bike on a roof where I can’t see it

What d'you think is going to happen to it? I think a lot of the worries (like @bikesandboots list) are really non events. I've been using various roof racks for 20 years now, and nothing has ever happened to put me off them. They're cheap reliable, transferable, and you don't need to arse about with the car's electrics.

To do know that Thule make half the manufacturer own brand bars and feet etc?

Half? And the rest...

My last couple of cars have had the "universal" rails. So it's now a standard fit for the clamp.

My OH’s car even though it was bought new with a manufacturer supplied and dealer fit towbar doesn’t turn off the rear parking sensors when she’s her horse trailer attached – so she’s to switch them off, which switches off the fronts too…

Sometimes the lightboard/trailer doesn't switch off the sensors if it's not set up properly, i.e. you're using an adaptor, or the trailer doesn't use "standard" pin layout. I know my mates trailer doesn't, but my caravan does...

Dedicated wiring kit and coding if you don't want parking sensor issues.

Some cars have parking sensors that are more sensitive to tow bars. On our current car we were advised to go removable because there is a known issue with fixed towballs interfering with the parking sensors due to their placement. If I leave the removable on then it does interfere.

Previous car, same fitter no issues with a fixed ball.

Last time I had 13 pin wiring for the ability to have reversing lights, to future proof and for the better bayonet plug. About £70 more. Probably not worth it for a bike rack though.

About 5 years ago there was a spate of bike thefts in our village over a couple of weeks. All the bikes that were stolen came from properties that had a car parked in the drive with bike carriers on the roof. Something to consider.

It's worth checking which of the driver aids get disabled when you've got something plugged into the electrics.  On my car, you lose the blind spot lights, but the cruise control/lane keep still work.  On my wife's Volvo, you also lose the "Pilot assist", which is a bit annoying.  Obviously it's not the end of the world, we used to drive cars fine without them, etc. but something to consider.

I've ended up with both roof racks and a tow bar rack, and prefer the tow bar rack for long journeys because of the wind noise with the roof bars, but beyond that don't have a strong preference.

I prefer roof carriers. Bikes on a rear carrier are going to be sprayed with all kinds of muck, think about how minging the boot of the bar gets. My mates a bike mechanic and can tell when someone uses a rear rack by the state of the bikes brakes etc through corrosion.

I'm not keen on adding more length on a car either, the rack is going to be hanging out of parking spaces.

But putting a bike on the roof of my RAV has worn thin, one of the reasons I'm going back to a regular car.

Bikes get sprayed with muck on roofs as well...doesn't really make any odds, but on a rack on the roof the bike is facing the direction of travel so a smaller frontal area but bike still gets sprayed (see the amount of spray when a truck goes past). Bikes on the rear, the bikes are sideways so have more surface to collect the mank, but I've not found much difference between the 2 in terms of keeping clean.

I prefer the towball - less effort to get them loaded; better fuel consumption than having them on the roof; I think they are more secure (they don't tend to wobble like they do on the roof) - however, they are probably easier to pinch, but you do tend to have a towing eye to secure a locking solution to.

Actually this talk has reminded me that I need to go check my roof carriers - they haven't been used for about 5 years and I've no idea if the locks still work!