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Alpinestars Nucleon KR-2I Back Insert - Black

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in Body Armour

CE approved Level 2 back insert for Alpinestars jackets and suits

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Customer Reviews for Alpinestars Nucleon KR-2I Back Insert - Black

Alpinestars Nucleon KR-2I Back Insert - Black
August 15, 2018

Safety first

Lightweight, breathable, comfy and reassuring it's there should the worse happen. Fitted straight into my Alpinestars Brera jacket. A must have. Adding to that great price and speedy delivery, both things Sportsbikeshop provide time and time again. 5 stars for both product and supplier.

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Alpinestars Nucleon KR-2I Back Insert - Black
July 29, 2018


I didn't want to spend the money on the Dainese one, I got this one and it fit in my jacket. 1 week later I had a crash and the back protector sure did help with keeping me safe.

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Alpinestars Nucleon KR-2I Back Insert - Black
July 15, 2018

Top quality back protector!

Thin & light with enough flexibility to mould nicely to your back when riding. Purchased the chest protectors too which all fit perfectly in my Alpinestars Jaws leather jacket. Great product.

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Alpinestars Nucleon KR-2I Back Insert - Black
May 4, 2018

I've been a naughty boy

Rumour has it that the Alpinestars Nucleon KR2i back protector insert also fits nicely into the jackets of their arch rivals Dainese! Have purchased one to try in my Dainese Razon jacket and can confirm the rumours are true. It fits great! The KR2i is lightweight, very flexible, amazingly thin (for a Level 2 protector) and very comfortable to wear. Its also excellent value for money. So whether you are an Alpinestars or Dainese wearer this back protector cones highly recommended. I wonder if Sportsbikeshop will print this? :-)

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Alpinestars Nucleon KR-2I Back Insert - Black
April 24, 2018

Feels good

Fits well in my Alpinestars jacket.

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Alpinestars Nucleon KR-2I Back Insert - Black
March 2, 2018

Hope I'll never need to test it

Fits well. Much better than the foam padding you get as standard on Astars stuff ...

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Alpinestars Nucleon KR-2I Back Insert - Black
February 16, 2018

Fast delivery of a quality product

Fast delivery as usual, the back protector is light and fits perfectly in my leathers. It's designed to contour to your back and is much more comfortable and less bulky than the (temporary) RST, I fitted.

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Alpinestars Nucleon KR-2I Back Insert - Black
January 22, 2018

Nice but should be cheaper

Nice piece of kit, comfortable to wear & fits nicely into my textile jacket but I don't see why it's not cheaper.

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Alpinestars Nucleon KR-2I Back Insert - Black
January 19, 2018

Very good product

Product came brand new exactly as described. Very good bit of kit, hopefully when the time comes it'll prove it's worth. Very fast shipping time and excellent communication from sender.

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Alpinestars Nucleon KR-2I Back Insert - Black
January 18, 2018

Good product, fast delivery

Fast delivery. Good protective product: fits neatly into back of my jacket. Not too bulky and I don't notice it's there too.

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Alpinestars Nucleon KR-2I Back Insert - Black

OptionMaximum heightMaximum width

The latest in back protection inserts from Alpinestars is the Nucleon KR-2i soft back protector insert. Suitable for all Alpinestars jackets or suits that feature a back protector pocket. It's design conforms to the latest back protector standards with it's Level 2 CE-certification (EN1621-:2014). The 'Nucleon' back protector's design has been ergonomically profiled for an optimised fit, whilst the lightweight design and flexibility with incorporated airflow system helps to keep the wearer both cool and comfortable. This highly protective back protector is quick and convenient to insert and offers the perfect fit for the ultimate in safety performance.

Back protector compatibility chart

  • Level 2 CE approved
  • Lightweight, Flexible Design
  • PU Injected Impact Foam
  • Ergonomically Designed Profile
  • Perforated For Breathability & Comfort
  • Channel Ventilation System For Optimised Airflow


Alpinestars, a truly world class brand of motorcycle apparel. Founded in the early 1960s by Sante Mazzarolo, Alpinestars has grown to be a world leading manufacturer of professional racing products such as leather jackets, jeans, boots and 1 piece suits. Whilst their leathers are worn by some of the biggest names in bike racing, they also specialise in high performance textile jackets, jeans and gloves. From F1 to Karting, the World Rally Championship to NASCAR, Alpinestars work with the very best drivers and riders to bring design innovations to all aspects of professional motor-sport.

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Questions and Answers

Questions and Answers

  • Hi I have purchased an Alpinestar Jaws Leather Jacket off yourselves recently- size 42 chest. I'm 6ft 3" and slim. Jacket is snug but good fit. Which size would you recommend re. the back protector?

    September 6, 2018

    We would recommend the medium back protector.

  • Hi, looking at purchasing the Alpinestar GP plus R v2 size 46 U.K. Q1 is this the best back protector? Q2 what size for the 46?

    April 25, 2018

    This is the Level 2 CE approved back insert that Alpinestars recommend. If you were to purchase an Alpinestars Jacket in a UK size 46, you require the Large insert.

  • I have an Alpinestars Motegi Leather Jacket size EU56. Which size do I need as the compatibility chart isnt clear if they are using the Euro or product size?

    August 14, 2017

    You will need a size large for your jacket

  • I have an Atem one Piece suit 3 years old.It has no pocket for a back protector just the press stud fixings. How is the Nucleon held in place as there are no reciprocal stud fittings shown on the photos of the protector ?

    January 26, 2017

    This product is only suitable for all Alpinestars jackets or suits that feature a back protector pocket.

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