Aero roof bars worth it?

[Paul_B]

Are Aero bars worth getting? Got old steel, square bars which I can get feet set for my new car. This is my cheapest option but is it worth getting the aero ones?
Aero bars are supposed to be more fuel efficient. I'll only use them with a roof box and take both off after use. Basically to and from camp spot then if we're driving around on the holiday. The box and will stay on as well.
I can only think you'll save if you never take your bars off. If using with a box I can't see aero bars making enough difference. What do you use? Their use is on a car BTW not van or Landy.

 

[bushwacker bob]

If you remove them after use, I'm sure the extra mpg you have with them on wont make a jot of noticeable difference.If your really that concerned about the extra fuel you will burn, maybe you shouldn't use a car.

 

[Robbi]

Hmmm, useful comment Bob.

I use a large roof box on my estate car with standard square roof bars, I'll be perfectly honest and say that the extra fuel consumption is negligable, I do however take the box attached to the bars off when I don't need them, easy to store and put back on when needed.

 

[cbr6fs]

Aero rack with no box will offer a very very small fuel economy gain on some journeys (the slower the speed the less the gain).

Aero rack with a roof box fitted won't make a blind bit of difference.

 

[Paul_B]

What I thought. You hear figures of 15%extra fuel with bars on. Also read on a roof box/bar online retailer site that AA or RAC ran tests and determined bars give you a measurable fuel penalty but add a streamlined roof box and it is less. That doesn't sound right and it was on a retail site without links to the report or summary.
I'm not too bothered by it just curious if anyone has tried both types of bars and noticed any of the supposed advantages. Like reduced fuel usage, reduced noise/drag. My view is I use the bars and the box so I can do what I enjoy. As such I accept any negatives like noise. My old car when loaded up with a roof box full sometimes struggled. It's an old car. The new one has a bigger diesel engine and more power/torque so unlikely to struggle with the box on top.

 

[cbr6fs]

What I thought. You hear figures of 15%extra fuel with bars on. Also read on a roof box/bar online retailer site that AA or RAC ran tests and determined bars give you a measurable fuel penalty but add a streamlined roof box and it is less. That doesn't sound right and it was on a retail site without links to the report or summary.
I'm not too bothered by it just curious if anyone has tried both types of bars and noticed any of the supposed advantages. Like reduced fuel usage, reduced noise/drag. My view is I use the bars and the box so I can do what I enjoy. As such I accept any negatives like noise. My old car when loaded up with a roof box full sometimes struggled. It's an old car. The new one has a bigger diesel engine and more power/torque so unlikely to struggle with the box on top.

Problem with many of those figures are that they're too vague, throw in sales or a ad department and they're outright deceitful many many times.
If you were driving from the North of England to France on motorways then a aero bar would likely offer a noticeable saving.
If you were to pottle around the Lake district during the summer holidays then it's not going to make any real difference as you travel between traffic jams.

As i say with a roof box on the drag from any roof bar be it aero or not is going to be inconsequential in comparison.

Had a roof box for a while when the kids were younger, what with wind noise and loading/unloading it drove me crazy, once the kids grew out of pushchairs we just packed the car in with soft bags everywhere, it's surprising how much stuff you can fit in a car if you start cramming stuff into every nook and cranny.

Bit of a car nut and speed addict so even the family cars tend to be more on the sporty side, so i can't say as i noticed much in the way of drag, as we were holidaying on a Greek island there isn't much of a chance to get to motorway speeds either.

Did have aero bars on my 911 but that was for the pushbikes, it never had a roof top box fitted.
I did notice a a drop in MPG the odd time i left the bars on, no square bars as a comparison though.

The other thing is that you should add the cost of replacing the bars for aero ones into the equation.
If you only use the roof box once or twice a year, you don't do many motorway miles with it and have the roof box fitted i'd be very surprised if the aero saving was enough over say 5 years to get the cost of the aero bars back.

 

[Bucephalas]

I thought i had lost my aero bars and bought some square lidl ones. Quite a difference in noise but could never notice a fuel difference.
When my roof box was returned to me by a friend after a year he returned my aero bars too which i had forgotten he had.
No noise now.

 

[Paul_B]

Found old Thule square bars so academic now as just buying the fixing kit not bars as well. Was tempted at about £50more for aero over square bars when I needed the bars as well. I like the T fixing strip on them. Looked a good way to add attachments.

 

[rancid badger]

In my experience , the only real difference is in the amount of noise the square bars make, compared to the aero bars. My last three Fiestas have had Ford aero bars fitted from new and they're significantly less noisy than the Thule square ones I used to use. That said, they still make a noticeable racket, and I tend to remove them when I'm not heading off paddling or carrying something else on the roof.

On the question of fuel economy, I never notice any difference with the bars on, even when I'm carrying a 15-16 ft canoe, at motorway speeds.


I don't think I'd go back to Thule square bars but then neither would I use any Thule or other system for that matter, that didn't bolt to the roof like my Ford ones do.

 

[Paul_B]

I've got roof rails but theyre recesssed or slimline ones which only just stick up and not like a handrail on the roof but more solid along its full length. If it was the handrail type I'd have tried to fit my old Vauxhall ones from my Astra. I believe they fit a lot of roof rails just not these low level ones like on my SEAT.

I'd go for aero bars too but the extra money needed is not available. I need as reliable but cheap option as possible. I ain't getting a Paddy Hobkirks roof rack again!! They detach at speed with kayaks on them. Aero bars seem to be a lot more than square bars.

 

[palace]

My Audi Q5 came with factory aero bars apparently they "interface" with the stability control system!. With previous 4 X4's fitted with roof rails I had used Thule square bars, both types of bars unloaded make similar amounts of wind noise @ 70 mph, however with the aero bars when we strap my sons 4 meter Feelfree Corona sit on kayak on the roof the noise diminishes to a whisper??? also with an aero style cycle mount & mountain bike the noise also reduces though not by such an amount. I have also used ski mounts the guillotine type with sprung rubber edges perfect for 7 or 8 beach fishing rods though I normally have 4 rods they are also slightly quieter than unloaded rails.

 

[Paul_B]

Anyone with aero bars got a roof box?

I've got an Exodus 470litre box which is fixed by a u shaped double ended bolt. It goes up around the bars and into tubes through the base of the box and clamped tight by a mechanism inside. The trouble is an aero bar looks too wide to fit inside this fixing.

That might rule out aero bars. Can anyone with aero bars and roof box explain how they work together? I'm guessing the T bar fixing in the middle of the aero bars has a role in it but I just can't think how.

 

[benp1]

T track allows a single bolt to be used for a fixing

the wide U bars fit fine, it's also easy to fit to a roof box, you can drill holes easily in it the holes don't fit

i have Thule Wingbars and both roof boxes I've used have been fine

 

[Duggie Bravo]

I was able to buy the u-shaped bolts in the larger size to fit on the aero bars on my Disco. I think I got them from either Halfords or Land Rover main dealer, as they were the only two places I ever bought car accessories from in those days.


Sent from my iPhone using Tapatalk

 

[Paul_B]

Thing is on my roof box the holes in the fixing mechanism is a set distance apart. That distance is less than the width of aero bars I think. That means any u bolt wide enough would have to go in to fit those holes which would lift the box off the bars. Unless you put one side of the bolt through the centre of the aero bar somehow.

 

[benp1]

I had the problem on my first roof box, I just drilled extra holes in the right place. The U bolts are use a metal plate to brace the wing nuts (or similar) against so the actual hole doesn't really matter

 

[Mike_B]

I've had aero bars back in the day, and these days I use square bars. I can't honestly say there is any noticable difference in noise, and the aero bars certainly didn't seem to be any more efficient in terms of fuel usage. Depending on speed, with either bars on the car I reckon about a 10% increase in fuel usage. That set up includes a pair of "J" cradles to carry sea kayaks. Interestingly, even with two boats on the car I still see the same 10% differential.

The aero bars created a minor problem in that the rounded profile made it slightly more challenging to fit the cradles - and I had to source longer bolts. When I changed the car, I just bought Halfords square bars (which I suspect are made by Thule anyway and are the exact same size) and a Thule fitting kit. The end result has now transferred easily between several vehicles. I would strongly council against Halfords own fitting kit though - and I'm not that impressed with the other Thule offerings for kayak transport - KariTek cradles are significantly better. As with all things, you get what you pay for.

When not needed, the set comes off the car - that 10% at todays prices makes a difference!

 

[cbr6fs]

I've had aero bars back in the day, and these days I use square bars. I can't honestly say there is any noticable difference in noise, and the aero bars certainly didn't seem to be any more efficient in terms of fuel usage. Depending on speed, with either bars on the car I reckon about a 10% increase in fuel usage. That set up includes a pair of "J" cradles to carry sea kayaks. Interestingly, even with two boats on the car I still see the same 10% differential.

The aero bars created a minor problem in that the rounded profile made it slightly more challenging to fit the cradles - and I had to source longer bolts. When I changed the car, I just bought Halfords square bars (which I suspect are made by Thule anyway and are the exact same size) and a Thule fitting kit. The end result has now transferred easily between several vehicles. I would strongly council against Halfords own fitting kit though - and I'm not that impressed with the other Thule offerings for kayak transport - KariTek cradles are significantly better. As with all things, you get what you pay for.

When not needed, the set comes off the car - that 10% at todays prices makes a difference!

A lot depends on the car though Mike.

With something modern with a half a decent drag coefficient doing motorway speeds it'll make more of a difference than something with the aerodynamics of a garden shed like say a Defender doing 50mph flat out.

 

[Mike_B]

That's true! I've had a 110 Station Wagon or two. All had the box section roof racks on them - the rack added noise and certainly had an impact on fuel consumption, but as the thing only did 12 - 18 mpg it was all academic anyway. They were all V8 - thirsty beasts! - Once got 8mpg on a run to the Lakes, fully loaded inside and topsides, with a massive 4 wheel trailer behind it, also loaded. Taking the rack off wasn't an option! Taking cross bars off the car is though!

Anyway - back to cars - I've got an old'ish Audi A4 Avant these days - and back in the day had new Passatt's, a few A4's and an A6 - all gave approx the same increase in consumption with the rack, and the aero bars were on an early A4. I'm not convinced they're worth the cost.