I bought 1 a couple weeks ago. XL size, seems snug and great for running around town. However this week I've been on the highway riding with strong winds blowing and there is a lot of noise in that helmet! Even with the ear plugs in!! Also feels like the helmet is being pulled up. Is this normal? Only going 60 mph.
I was wondering if a size smaller (L), would eliminate the problems?
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Shake your head vigerously side to side as if you were saying no. It should be firm. If you feel pockets of space open up it might be too big.

What I did on my helmet was put some clear tape over the vents on the top. This eliminated much of the noise and it's still cool enough to wear on a hot day. Before I did this it sounded like a 747 was about to land on me.

I had similar problems with my Shark RSI. Helmet aerodynamics are extremely important and any shortcoming is exaggerated by riding a naked bike at high speeds. Problems can come both in noise, such as a lot of booming from underneath the chin, and in lift or other forms of wind resistance. When you're riding and noticing the problem, try to tilt your head forward and chin down to see what effect that has. If that stabilizes the helmet or reduces the noise, there's at least part of the answer.

There are a lot of solutions at that point. Here in Texas, taping up vents is not remotely acceptable - but maybe that'll work well for you. Some prefer to spring for a windscreen while others change helmets. It's up to you what you'd prefer. I picked up an Arai Corsair and I'm an Arai Fanboy now.

Also, what sort of earplugs are you using? I've noticed huge differences in noise between some of the options out there.

I noticed that when I tilt my head, it adjusts better.
I also really tightned the strap down!
Ear plugs, foam, in deep!
I ordered a wind screen today, hope that helps!
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