Alpinestars Nucleon Kr-2i

Alpinestars Nucleon KR-2i Back Protector Insert Alpinestars developed the Nucleon KR-2i represents the evolution of the Bio Armor Back Protector [read more]
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  • > EN1621-1 Liv 2

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Regular Price: € 59,95

Price: € 53,90

  • Price without VAT for extra UE countries € 44,18

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Alpinestars Nucleon KR-2i Back Protector Insert Alpinestars developed the Nucleon KR-2i represents the evolution of the Bio Armor Back Protector Insert. The Italian brand has thoroughly reviewed its back for its jackets and jackets with ergonomic structure, enhanced ventilation, reduced weight and a new resistance levels. With the CE level 2 certification, back Nucleon KR-2i provides a level of protection thanks to its exceptional advanced materials. Nucleon KR-2i is designed to fit the compartment provided for this purpose in the back of the jackets in leather and fabric Alpinestars latest generation. Nucleon KR-2i ensures greater security without compromising your comfort.

Additional Info

Product Code A650161510
ID 550
Color Black


Review by
Ordered this for my Alpinstars Atem jacket. Item fits well (is about 2.5 - 3 cm shorter than default Styrofoam insert), is light, extremely well perforated and seems to be very mold-able (will contour around your back when worn). The only downside I can see with it (and it's really more of a minor concern) is that the Large is only about 45cm whereas the jacket insert pocket is about 50cm, thus it's not utilised to it's fullest potential, however luckily the jacket has a hump between the top of the protector and the helmet, so I imagine it's save coverage. Was told to order this in size Large for jackets 52 and medium in jackets 50- (Posted on 27/01/2015)
Nucleon is a solid piece of protectionReview by
I was searching for a decent CE Level 2 back protector to replace the foam insert in my 10 year old Alpinestars TZ1 Jacket (size60). I found this insert at Motostorm and just added it to my order. The large fits right in the back pocket, although there is some play. I could have used an XL size but the material is not very flexible and it would not fit in the pocket opening. However, I am very satisfied with my purchase and feel better protected. Once again great shopping experience with Motostorm. (Posted on 31/03/2015)
Solid protection at a great priceReview by
I ordered this back insert for my Alpinestars GP-M jacket. I ordered a size Medium for my size 50 jacket. It fits the pocket inside my jacket very well, it is not overly bulky but yet feels like it would be very protective.. (Posted on 25/08/2015)
Great DesignReview by
Ordered for a size 46 Alpinestars jacket and fit perfectly. Protector is flexible and moulds over a short period of time to the shape of body. Good ventilation and can also feel the level 2 protection. Currenty riding with it in a Dainese Jacket. (Posted on 30/08/2015)
It doesn't noticeably interfere with the back ventilation. It's flexible enough Review by
A universal fit, at least for Alpinestars' jackets. It fits comfortably into my Valparaiso jacket and doesn't noticeably interfere with the back ventilation. After several months of riding with it I know It's flexible enough so that I may shift on the motorcycle without feeling resistance. I'm happy with this product, especially knowing it's ranked for the CE-2 standard. (Posted on 19/09/2015)
ExcellentReview by
Coming up to 3 years use and I'm very happy with its durability, lightweight, mouldability and compact shape. makes it an easy fit in most of my jackets. Very confident in the level 2 CE protection. (Posted on 25/11/2017)
Lightweight and comfortableReview by
I used the Nucleon Kr-2i (size M) for two years in my Alpinestars Andes jacket (size M). It fits in the pocket easily and once installed it is hardly noticeable even when riding with a backpack for hours. (Posted on 19/03/2019)
You need thisReview by
This back protector is 100% worth it for the small price it is. When I am riding I don't even feel like I am wearing this back protector, it doesn't add much more weight to the jacket and doesn't hurt my back (Posted on 15/02/2020)
Good stuffReview by
Used this in my viper air v2 for last season, never fell but I know if I did this would have been great protection! I think you should decide if you want even more protection with CE-2 protection. I ordered a Large with a Large Viper Air v2 jacket (Posted on 09/05/2022)
Solid Back Protector, Fits Alpinestars Jackets perfectlyReview by
The large is a perfect fit for the size 52 jacket, and offers full coverage since this is the smallest jacket size that fits the large protector. Other than that, it's a back protector and it feels like it should absorb impact pretty well but I don't want to test it! (Posted on 15/05/2022)
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