GiroRadix MIPS Adult Dirt Bike Helmet

After some shopping and research, I went with the Radix primarily for two reasons. First is that the sizing. I wanted a fitted helmet, not a ‘One Size fits most’. I figured getting a fitted helmet would be more comfortable and more secure. My head was right at 56 CM and the medium fits me well. The second reason was colors. Other models, like Fixture, had some real issues with grey and the visors not color matched to the helmet. The Radix had some great colors and I kept going back on forth. I went with the two-tone grey/lime. I really like the color. The top is a is a dark matte grey and the lime is more green than yellow, but is glossy in finish. Overall happy with the helmet. Good price, good ventilation, looks good, and good adjustability from the Roc-Loc.

I have been riding with a fox helmet for the last 7 years, and I always bike through the winter without one because it is not large enough to fit over a beanie, and no one will make a large enough helmet, and I don't want to sweat inside a ski helmet, even though they really look cool. After looking for smith everywhere and never being able to find the XL version, I finally found this, and ordered the largest size. It fits great at about 23.5" with nothing but a bandanna, and the mips is a huge huge improvement in comfort, and was very easy to adjust. I did not think I would like the "y" connectors beneath the ears, but they actually work really well. Set the female buckle side first, pull the cord through to the other side, set the other side, and clip off the excess webbing, and singe the end with a lighter; good to go. The visor flips up just enough to fit a headlamp for night riding, and the helmet tilts back and fits large snow goggles. The only complaint I had, was...why don't helmet manufacturers put headlamp and goggle guides on every single helmet? Haven't we figured that out yet? So I spent a day looking at all the terrible 3m glue things that I know will melt and mush off my helmet and make it look like crap, and then I finally settled on using black midgrade size zipties, the 8" black ones. You can position them and route them under the mips so you don't feel them. If you are looking at the helmet from the rear, don't use the middle holes, but the holes to the left of the middle, and to the right of the middle. And that would be the holes on the upper and the lower, with the middle ones left open. So you put four ties, one in each corner, and position the part that zips down so the nub is sticking out. They make perfect little permanent non-glue goggle and headlamp catches, and it doesn't clutter up the helmet and make it look bad. I also added two on the front where the visor flips up, in the center hole, so you can shake your head like crazy as if you were riding over logs, and now your headlamp won't slide off the front of the helmet and slap you in the face. 6 zipties, and you are good to go. Awesome helmet, so comfortable and easy to adjust. Incorporate goggle straps and it is great!

My head is basically exactly at 23in so I took a gamble getting the medium size instead of the large since it was cheaper and in a cooler color. The size guide says medium only goes to 23in for the biggest and large is 23in at the smallest. After getting it though the box says 21.75-23.25in. So it fit perfectly! If you're head is in-between the two sizes, keep in mind that the medium actually goes up to 23.25in and not 23in.The helmet looks great, fits perfect, and is exactly what I was hoping for! Would recommend!

Commuter, low speed recreational cyclist here. I like the color and it doesn't look horrible. Lets be honest, all bike helmets look dorky, but they are important safety gear that should be worn. The Roc Loc system let me dial in the helmet for a comfortable and secure fit. This is so much better than the last helmet I bought in the 90's. I don't want to put it to the test, but if I crash, I feel that this helmet will protect my melon.

We have owned several different Giro helmets and they are generally a good value. The Radix is another great helmet. Lightweight and well built. Decent coverage for this stye of helmet. Comfortable and enough adjustments to get a good fit. Enough venting to keep it comfortable on hot days.

good fit, could use a little longer bill for the morning sun

Very comfortable, lightweight and good looking.

The fit on this helmet is great. I realize that's a very personal thing and just because it fits me doesn't mean it will fit you.I've had several Giro helmets over the years. (Including the first one with a Roc Loc system in the early 90s!) The last time I bought a bike helmet I got a good deal on a Bell and it was fine. But helmets age out after a few years and need be replaced, so here we are. Also, I recently replaced my motorcycle helmet with a Bell MIPS and I wanted to upgrade to a MIPS helmet for the bike, too.I had forgotten how well Giro helmets fit me and I'm loving how comfortable this one is.If I had to come up with any negatives, I only have a couple minor nit picks. The visor is a little shorter than I like, another half inch (12ish mm) would have been good. Also, I did like the no pinch buckle on the Bell. I'm in my 50s now and the skin under my chin is a little looser than it used to be. The first time I tried this one on, I pinched myself because I was out of the habit of ensuring the buckle wasn't against my skin when I snapped it closed. Ouch.