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Why wait? We now provide some of the best finance packages around to help spread the cost and get you on the road. We now offer finance on most orders from as little as £280 with 0% packages starting at only £300. The online application process is super simple too and takes around only 5 minutes to complete! The best part is, there's no paperwork to print and in most cases you'll have a decision in under 10 minutes. Just select finance as a payment method and take it from there!

10+ Years Online

We've been serving the motorcycle community for more than 10 years now and in that time we've grown to be the largest online retailer of motorcycle clothing & accessories in the UK.

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We now offer free returns on any UK Mainland order (excluding Highlands) over £25. Most importantly, returning an item to us is super simple. Just click here or on the 'create a return' link located at the bottom of every page, and create your return in under 1 minute. You can choose from any UPS Access point close to you where you can drop off your return at a time convenient for you.

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We simply don't believe in making the sale and moving on, we want to make sure our customers are happy with their purchase. That's why we now offer a full 365 day returns period. Simply relax, take your time and make sure it's right! All we ask is that you try the items within your own home and return with the tags intact.

190+ Top Brands

There simply isn't a better selection of biking brands anywhere in the UK and we're constantly updating every range to ensure you have the best choice available.

80,000+ Products

Our stockholding is now in excess of £10 million with over 80,000 items in stock, ready for next day delivery. We also believe in offering our customers the very best choice, with more than 190 brands on offer and a range to suit every budget.

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

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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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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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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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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December 26, 2017

Very comfy

Excellent value, easy fit into the jacket, very comfy and well worth purchase. Pity it wasn't a standard fit but very happy, thank you.

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November 10, 2017


Fits nicely in jacket and doesn't feel like you have a board on your back!

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October 10, 2017

Feels great

Fit nicely into both my Scorpion and Alpinestars jackets. It feels light and doesn't rub or press in anywhere. Haven't crashed yet, but I'm optimistic!

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September 2, 2017

Brilliant product

Fits well, light, with enough flex to work with while not riding.

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August 30, 2017

Good unobtrusive back protection

The Alpinestars Nucleon KR-2I Back Insert was very simple to fit into my Drystar textile jacket although at first it seemed a bit stiff, but once wearing the jacket it soon softens and moulds to your shape. After a short ride I didn't even notice wearing it. So very pleased with the extra protection it will provide if a ride doesn't go to plan. It was also delivered earlier than predicted.

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August 7, 2017

Great light-weight back protector

I bought this to use with the Alpinestars Amok Drystar Textile Jacket, which it fits perfectly. Wanting something with good protection, whilst being light-weight, this product is barely noticeable whilst wearing and also with the holes gives great breathability without compromising the CE L2 protective ability.

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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

  • 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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