Yakima roof bars package - S46 Aero-X silver bars

Yakima's Aero-X roof rail bars not only include the award winning Whispbar aerofoil-shaped bar but are ultra-low profile; they fit between the roof rails. If you're just carrying a roof box or a couple of bikes or kayaks this might be ideal, but if you want to maximise the load carrying potential of your car then you should be looking first at Yakima's "through bar" system with fitting kit 328. Please note that it doesn't matter if the edge of a roof box rests on the plastic covers at each end of the Aero-X bars - just be sure before ordering that the T-track slot is as long as the distance between the roof bar fitting points in the roof box.

Basic geometry:

• These bars fit to longitudinal roof rails which are between 104cm and 111cm apart (up to 114cm apart when the bars are at full stretch).
• The T-track slots on these bars are between 85cm and 92cm long (up to 95cm long at full stretch), i.e. they are 19cm shorter than the distance between the roof rails.
• If e.g. your roof rails are 107cm apart (inside face to inside face) then the T-track slot will be 107cm less 19cm = 88cm long.

Other features and specifications:

• These bars look good and sound good, but they also feel good. They're beautifully made, are supplied fully assembled, and are relatively quick to fit.
• They have a maximum loading limit of 75kg - but please check your vehicle's load limit as it may be less than this.
• All roof boxes, and all accessories that can be fitted to Atera, CRUZ or Thule T-track aluminium bars, can be fitted to these roof bars.
• Other manufacturers supply a rubber strip that you need to cut and press into the bar between the accessory fixings. But with Whispbar the rubber is already in place, within the slot - it's called Smartfill and is a Yakima patent.
• Locks are supplied as standard.
• Please note that because Whispbars are 85mm wide you will need T-track adapters to fit almost all products except a limited range of roof boxes. If you are buying these bars on their own, check your roof box fittings to see if they are wide enough and be sure to order what you need!

Yakima is (along with Thule) one of the two largest brands in the global car rack systems sector. Their Whispbar profile was the culmination of many years of design and innovation by Hubco Automotive, whose chief designer transferred his aeronautical design experience and know how to the roof rack sector, working closely with the engineering school at the University of Canterbury, New Zealand.

The Whispbar aerodynamic profile was launched at the Frankfurt Automechanika trade fair in 2008, since when many other roof bar manufacturers have launched low drag / low noise roof bars. But none of these is as efficient, as low drag, as the Whispbar profile, partly because Hubco Automotive (now owned by Yakima), who created the whole concept and underpinned the designs with serious science, patented crucial aspects of their design.

The aim of this note is to persuade you that kayaks should always be tied to the carrying vehicle at both bow and stern.

Untied kayaks have, in our experience, the greatest potential for a roof bar or kayak carrier failure. The massive forces that untied kayaks can generate have even been known to snap roof bar fixing bolts with the result that a complete assembly of roof bars and kayaks has ended up on the road. We know that this has happened with almost every brand of roof bar, and regardless of whether the kayaks are on a special carrier or just strapped to the bars.

You need to fix bow and stern lines, probably using the front and rear screw-in towing eyes to get strong and accessible fixing points on the vehicle. Kayak shops should be able to provide suitable 'paracord' for this purpose. Alternatively, we have sets of straps available that are perfect for the job and are really easy to use. Yakima make some excellent Bow/Stern tie down straps and Thule makes the QuickDraw 838 which we have listed together with every kayak carrier we sell.

Please note that kayaks should be strapped to the roof bars, or to kayak carriers, using straps that are suitable for the purpose, e.g. 25mm polypropylene straps with strong buckles. Bungee cords must never be used.

Please also note that all roof bar instructions point out the dangers of carrying unsecured long items, as of course do all kayak carrier instructions.

If you tie down your kayaks properly you almost certainly won't experience a product failure. If you don't you may or may not get away with it. If there is a disaster and the kayaks end up on the road, separated from the vehicle, then you were not using tie downs and you have subjected the roof bars to forces for which they were not designed. The costs of sorting this out are yours, not ours, and you may also have difficulties with your insurers.

We're sorry to be so firm about this, but "things coming off the tops of cars" is the stuff of nightmares, and we want to do all we can to prevent accidents of this sort from happening.

Delivery charges and arrangements:

We charge a contribution towards delivery costs, depending on what you order, where you live, and how quickly you want the goods.

These are our standard charges; there are usually surcharges for all offshore destinations and some remote postcodes - for details please see our delivery information page.

Delivery of other items

Delivery times

Delivery times are calculated in working days (Monday to Friday, excluding Bank holidays).

Cut-off times for Express Delivery orders
Express Delivery orders placed before before the cut-off times shown below will usually be desptached on the date of order. Express Delivery orders placed after these cut-off times will be despatched the next working day.

Delivery FAQs

When will my order arrive?
There are no deliveries on Saturdays, Sundays or Bank Holidays, except for postable items where Royal Mail has a Saturday delivery. Express Delivery orders placed on a Friday (before 1pm) should be delivered on the Monday or Tuesday, Express Delivery orders placed on a Saturday or Sunday should be delivered on the Tuesday or Wednesday. The arrangements for Very Heavy Items are different and are shown above.

What about Next Working Day delivery?
Most Express delivery orders will arrive on the next working day, if the order is placed before the cut-off time (see above). Some will arrive on the second working day if there has been a "split-delivery". So-called “split deliveries” happen when the couriers do not have enough trailer space for everything that should be moved around the UK, so they will load what they can and leave the rest for the next trailer.

Is my delivery day guaranteed?
No retailer or courier company can ever "guarantee" a Next Working Day delivery. As well as split deliveries, all courier companies occasionally have the same transport problems as can happen to everyone else, including snow blocked roads, closed roads, traffic jams, mechanical breakdown, an inability to find the delivery address, or to gain access to it if, for example, it's in a block of flats. We work with some of the best couriers in the business, and overall they provide an outstanding service.

Do I need to be at home?
We are very flexible with our deliveries and will aim to deliver to an address which suits you – this does not need to be your home address. Goods can usually be left without signature - we prefer this with roof boxes. There's a "Special Delivery Instructions" box in the checkout area where we'll ask you to choose a typical instruction and then amend it to suit your particular requirements.

Payment options:

We take the following cards, and also PayPal. Please note that the entry on your card statement will be from "The Roof Box Company".

Secure payments

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Yakima's Whispbar roof bar profile is still the most aerodynamic shape available, with less drag and less noise than any other roof bar shape. Reduced drag means better fuel efficiency.

The aerodynamic profile was launched at the Frankfurt Automechanika trade fair in September 2008 - a mini wind tunnel was shipped in from New Zealand to show off the new technology. This was a long time ago now, but the fundamentals haven't changed.

Note that the Whispbar profile was developed by Hubco; their business was later purchased by Yakima.

Hear it for yourself. The commentary is a bit long-winded, but this video is still a unique insight into the noise that roof bars make, and the difference between square bars and aerofoil-shaped bars. Competitors have caught up as much as they can, to the extent that the human ear cannot tell the difference between the noise generated by several brands of roof bar profile - but the patented elements of the Whispbar profile still give it a much lower drag coefficient than its competitors.

Roof top tents should not be fitted to these bars!

Roof top tents should only be carried on through bars, the type of roof bars where the cross bars stick out beyond the feet.

There are concerns for both safety and damage if flush bars are used.

Flush roof bars have a plastic-covered foot at each end of the bar. Even if the cross-bar part is wide enough for the roof top tent to be fitted, the tent will certainly be wider than the bars and the weight of a person pressing down on the raised foot can damage the plastic parts. From a safety perspective, the base of the tent is unlikely to be touching the cross bars, so it will be difficult to tighten the fixings correctly, and the fixings of some tents can loosen when people are in the tent, and it flexes.

Full size platforms such as the Thule Caprock and the Yakima LockNLoad platform should also not be used on flush roof bars; they tend to be heavily loaded, and to be walked on.

This is an easy problem to solve; please choose a pair of through bars - the type of roof bars where the cross bars stick out beyond the feet.