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Alpinestars Nucleon KR-2I Back Insert - Black

Alpinestars Nucleon KR-2I Back Insert - Black

Customer Product Reviews

5 Stars from 84 reviews

Our price £37.99 £39.99
Showing 1 - 20 of 84
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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July 26, 2017

Perfect all round back protection

Alpinestars have yet again produced another high quality product to help reduce the risk of serious injury in the event of an unfortunate accident. The back protector molds to your individual shape whilst worn. Wouldn't leave home without it! Essential kit...but fingers crossed I'll never need it!

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July 24, 2017

Great product

Perfect fit for DXR Skybolt Leather Jacket (L). Great advice received by Sportsbikeshop Customer Service Team (Antoine). This Alpinestars Nucleon KR-2I Back insert fits like a glove into my DXR jacket. The material is thick but light and flexes enough to fit into the jacket. It adds great protection to my back and doesn't restrict my movements while riding and the perforations keep my back dry in warm weather. Its memory foam like composition feels very comfortable, I don't realise I've got it on. Great product!

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July 20, 2017

Perfect for A-Star leather suit (with race hump)

Delivery: SBS as always, quick and well packed. Price : reasonably priced as per current market Quality: A-Star cannot be faulted. Feels like a solid piece of armour compared to the ordinary foam that it replaced in the A-Star Challenger suit trouser - Back section. this is a LEVEL 2 protector. Fit: Perfect fit as expected. They seem similar to D3O armor. If you squeeze its soft and if you punch it feels hard. Surely similar properties if I am not mistaken. It does mould to your body to an extent as claimed by some reviews, but that is a good thing. My suit has a race hump (medium size) and inserting this back protector doesn't change the fit and feel of the suit. The suit does get slightly snug but that could be also due to the fact I have also added chest inserts as well. Feel: Doesn't cause any discomfort. Feels as if it was already part of the suit. Also invokes confidence in the suit. Wore it during a very hot day and didn't seem to change the comfort of the suit compared to when there was only foam. It's perforated well so does breathe. Test: Hope will never have to. confident it will do the job. Recommendation: 5/5

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July 18, 2017

Just the job

Fitted perfectly in my Alpinestars summer jacket. Was light and flexible. Hopefully will do it's duty in a time of need. Have bought a few things from Sportsbikeshop. Always good value and prompt.

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June 28, 2017

Snug fit

Just slotted in to my Drystar jacket, light and comfortable. Well made and moulds to my riding position. Well done Alpinestars and well done Sportsbikeshop, top quality service as usual.

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June 20, 2017

Just the job

Snug fitting back-pad for Alpinestar ladies Stellar jacket that fits inside jacket pocket. Size Large for ladies 2XL size jacket. Flexible and unobtrusive - just the job.

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June 5, 2017

Light and unobtrusive

Excellent product at excellent price! Well done Sportsbikeshop, best price in the marketplace.

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June 1, 2017


A very flexible and comfortable back protector. Fits snugly into the jacket and I don't feel it when riding. I only hope I never test out it's protection properties.

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May 29, 2017

Worth it...

It would be great if these were included with the jackets rather than as optional extras, but you can't have everything I guess! The fit is really great in my Alpinestars Vence - These back protectors fit nice and snug in the special pocket in the back of the jackets and are comfortable once in place. All in all, hope I never get to test it, but happy so far!

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May 25, 2017

Cheap at half the price

I'm using this in my Dainese Avro Jacket and it's a spot on fit. I did originally order the Dainese Manis Back Protector, which was easier said than done due to stock levels and when it turned it it was too big for their own jacket. The Dainese item was almost twice the price of this one so I decided to take a punt and it fits perfectly. It's made out of a kind of high density articulated foam, the same material as their chest protectors, and moulds to your back. When the jacket's on you get the reassuring feels it's their but it's not uncomfortable. Would recommend and it's worth a try first if you have a Dainese jacket.

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PLEASE NOTE: The views and opinions expressed in the above reviews are solely those of the author and are not necessarily representative of the views of SPORTSBIKESHOP LTD.