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Nice car; nice rack. I'm not sure about this - but I think you need to be careful when you bolt-down the roof rack stanchions / towers onto the (hidden under-the-little-"doors") bolt-down brackets. Does Mazda give a torque spec or a max. number of bolt rotations in their instructions for the roof rack? The reasons I mention this are i) you don't want the bolt-ends to contact and dent the roof surface / and/or break the integrity of the roof paint - and cause rust to start there (if the brackets WOULD allow that to happen); and ii) some folks have over-tightened the bolts and have caused the roof brackets to bend (upwards) thereby preventing the little plastic "doors" from being able to be put back into the roof seam reveal moulding (when the towers are removed).

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Discussion Starter #3
Nice car; nice rack. I'm not sure about this - but I think you need to be careful when you bolt-down the roof rack stanchions / towers onto the (hidden under-the-little-"doors") bolt-down brackets. Does Mazda give a torque spec or a max. number of bolt rotations in their instructions for the roof rack? The reasons I mention this are i) you don't want the bolt-ends to contact and dent the roof surface / and/or break the integrity of the roof paint - and cause rust to start there (if the brackets WOULD allow that to happen); and ii) some folks have over-tightened the bolts and have caused the roof brackets to bend (upwards) thereby preventing the little plastic "doors" from being able to be put back into the roof seam reveal moulding (when the towers are removed).

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Gotcha, thanks.
 

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How is the noise? I’ve had several cars With racks that made almost no noise and a Honda Fit with roof rack that sounded like a 747.
 

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What's your sense about how either strong- or weak minded the actual brackets are... the ones on the roof, below the roof seam reveal moulding "doors"s? Are they stout?
 

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Rack impressions: Install was very straight-forward and took about ten minutes going slow and carefully. It looks good and feels well made and sporty looking in real life. Without the bungee wrap at low speeds the rack is pretty quiet if it's not windy. At higher speeds 50mph and up it definitely has a rumble like airplane wings. With a bungee spiral it reduces the noise about 75%. At higher speeds or if its pretty windy you still hear it but not terrible. I rewrapped the bars with a wider spiral and I like the look better but the tighter spiral is a bit quieter.
 

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Rack impressions: Install was very straight-forward and took about ten minutes going slow and carefully. It looks good and feels well made and sporty looking in real life. Without the bungee wrap at low speeds the rack is pretty quiet if it's not windy. At higher speeds 50mph and up it definitely has a rumble like airplane wings. With a bungee spiral it reduces the noise about 75%. At higher speeds or if its pretty windy you still hear it but not terrible. I rewrapped the bars with a wider spiral and I like the look better but the tighter spiral is a bit quieter.
I’d be curious to hear your wind noise impressions if a front fairing was added. I never really drove mine without that part, but it is ungodly loud. Unless I have the bikes up there I keep the sunshade closed to block the noise. If I have the sunroof open, it sounds like the inside of a small airplane with the amount of noise it makes.
 

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I have installed the Mazda roof rack on my 2018 hatchback, without any fairing. The wind noise is not objectionable at all to me. I think this is because the cross beams have an airfoil shape, and each beam has a unique angle of attack. I strongly suspect that Mazda designed and tested the roof rack system using CFD and/or wind tunnel testing to minimize drag and noise. IMO that's worth the small price premium that Mazda charges over generic competitors' variants.

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It's a three letter acronym, for Computational Fluid Dynamics. It's an analytical tool, not unllike a virtual wind tunnel, used to predict fluid flow rates, velocities, pressures, etc. The predicted results are usually verified with measured test data.

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Some people like the look and function of fairings but I’m not a fan. Fairings can often vibrate and make noise even worse and rub through the roof paint over time where it contacts . They also make it more difficult to actually use the racks. They also tend to loosen and need retightening. For me bungees is my preferred method to quiet The wind noise. I drilled holes from inside the end caps to start the bungees for a cleaner look.
 

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Some people like the look and function of fairings but I’m not a fan. Fairings can often vibrate and make noise even worse and rub through the roof paint over time where it contacts . They also make it more difficult to actually use the racks. They also tend to loosen and need retightening. For me bungees is my preferred method to quiet The wind noise. I drilled holes from inside the end caps to start the bungees for a cleaner look.
It seems as thought Yakima solved some of the issues you bring up.

The way it secures to the rack is pretty secure and almost impossible to even purposefully get off. They also provide clear shield for underneath the feet, after a season and a half of use, there is no obvious marking at all.

Why do you say they make it harder to use the crossbars?
 

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It's a three letter acronym, for Computational Fluid Dynamics. It's an analytical tool, not unllike a virtual wind tunnel, used to predict fluid flow rates, velocities, pressures, etc. The predicted results are usually verified with measured test data.

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Thx...

Related, I guess the straking with the bungee cord impacts the vortex shedding frequencies in a favourable manner (no sympathetic mechanical natural frequencies coincident with the aerodynamic frequencies - like for the Tacoma Narrows bridge). Std discussion for all Mechanical Engineering students... This matter aside (mechanical natural frequencies are not at issue here); rather it is the vortex shedding frequencies versus the noise they generate, moderated / changed by the straking... and the aero resistance - presumably lessened.
 

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I took a few pictures of my Mazda Whispbar roof rack. Notably, the cross beams are each:
1) arched to match the roof curvature from left to right
2) airfoil shaped (i.e. rounded front edge and pointed tail edge)
3) angled to match the roof contour from front to back
Obviously, considerable thought went into their design. I can't tell from the photos if the 2019+ model roof rack has similar features.


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Discussion Starter #20
I had the dealership install it when I purchased it. Love the look of the Aero package.
 
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