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Alpinestars Nucleon KR-1i Back Protector Insert

Item: P295328

The Nucleon KR-1i form fits to your body. Great airflow and lightweight, the Nucleon KR-1i replacement back protector insert is CE Level 2. Read More

$79.95
Learn More

Product Details

Alpinestars Nucleon KR-1i Hybrid Back Protector Insert

The Nucleon KR-1i Hybrid Back Protector Insert is CE certified Level 2 to the latest back protector standard revision (EN1621-2:2014). Fusing together a lightweight, perforated hard shell and energy absorbing foam, this hybrid protector insert offers excellent impact resistance while being flexible and anatomically contoured. With its innovative cooling airflow channel system the Nucleon KR-1i Hybrid Back Protector Insert offers optimized levels of protection and comfort for sport and street riding.

Fitment:

  • Women's Stella Jackets:
    • XS-SM: Small Nucleon
    • MD-2XL: Medium Nucleon
  • Men's Jacket:
    • 48-50 or XS-MD: Medium Nucleon
    • 52-64 or LG-4XL: Large Nucleon 
Product Style RevZilla Item # MFR. Product # Availability
Product Style SM RevZilla Item #1012260 MFR. Product #6504115-12-S AvailabilityIn Stock: Ships within 24 hours
Product Style MD RevZilla Item #1012261 MFR. Product #6504115-12-M AvailabilityIn Stock: Ships within 24 hours
Product Style LG RevZilla Item #1012262 MFR. Product #6504115-12-L AvailabilityIn Stock: Ships within 24 hours

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Product Description
The Nucleon KR-1i form fits to your body. Great airflow and lightweight, the Nucleon KR-1i replacement back protector insert is CE Level 2. Read More
Part Numbers
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Shipping & Returns
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Reviews & Questions

4.8 / 5.0
58 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
46
12
0
0
0
Bang For The Buck
4.6 / 5
Protection & Durability
4.8 / 5
Features
4.4 / 5
Comfort
4.7 / 5
Style
4.7 / 5
Air Flow
4.7 / 5
Fit
Small
True
Large
Bang For The Buck
5 / 5
Protection & Durability
5 / 5
Features
5 / 5
Comfort
5 / 5
Style
5 / 5
Fit
Small
True
Large
Air Flow
5 / 5
Useful
hopefully i never have to use it in a crash, but like a condom, better safe than sorry
October 26, 2015
Purchased
over 2 years ago
Ride:
2015 Kawasaki Ninja ZX-6R ZX636
Bang For The Buck
5 / 5
Protection & Durability
5 / 5
Comfort
5 / 5
Style
5 / 5
Air Flow
5 / 5
Worth it!
I love this product. I also purchased the Alpinestars Stella Eloise Air Jacket in a size Small and the Alpinestars Nucleon KR-1i Back Protector Insert in a size Small. This is a bit thicker than my previous protector, which takes up more space in my jacket. I ordered my new jacket a size up and it fits perfectly. This protector is made with a memory style material so it form fits to my body. It has great airflow and it's light weight so it's worth the few extra bucks to upgrade. Keep in mind, if your jacket is already tight through the chest, this may not fit comfortably.
June 15, 2015
Ride:
2014 Kawasaki Ninja 300 ABS
Bang For The Buck
4 / 5
Protection & Durability
5 / 5
Features
4 / 5
Comfort
4 / 5
Style
5 / 5
Air Flow
4 / 5
Great back protector insert
Fits my Alpinestars T-GP Pro Air perfectly. High level of protection with minimal weight and bulk plus fair amount of wind flow. Comfortable -- don't really notice it's there while riding. Great product although a bit pricey.
August 2, 2016
Ride:
2004 Yamaha FZ6
Bang For The Buck
4 / 5
Protection & Durability
5 / 5
Features
4 / 5
Comfort
5 / 5
Style
5 / 5
Air Flow
4 / 5
Can't tell it's even there
I purchased this vs the KRR or KR 1 because of price and the fact it goes into my jacket instead of strapped onto my body. I only do basic track days at this point and may upgrade to the Nucleon KR1 later as I improve. But the quality and safety rating of the KR1i is about as good as the others. I cannot even tell its in my Atem jacket unless I turn sideways in a mirror. The air flows the same as it did with the jackets factory supplied foam insert. I hope I never need to know how well it works.
May 29, 2016
Purchased
1 year ago
Ride:
2014 Ducati Monster 1200 S
Bang For The Buck
5 / 5
Protection & Durability
5 / 5
Features
5 / 5
Comfort
5 / 5
Style
5 / 5
Air Flow
5 / 5
Great fit
Makes jacket slightly heavier but not bad at all. Flows air well also
November 30, 2015
Ride:
2008 Honda CBR600RR
Bang For The Buck
4 / 5
Protection & Durability
5 / 5
Features
5 / 5
Comfort
5 / 5
Style
5 / 5
Air Flow
5 / 5
A Practical and Affordable Insurance Policy
Taking a point off bang-for-buck is probably because I'm unsure how 1KN of force translate into nearly double the price? But since it's something that would probably keep my back and spine from shattering, it's either go big or go to the hospital. Of course, the while plastic insert increases the protection level, but adds a touch more of rigidity, the edges still feel soft and with it facing my back, it conforms exactly to it without being a radiator I'm carrying on my rides.
July 20, 2015
Purchased
over 2 years ago
Ride:
2015 Honda CB500X
Bang For The Buck
5 / 5
Protection & Durability
5 / 5
Features
5 / 5
Comfort
5 / 5
Style
5 / 5
Air Flow
5 / 5
Excellent lightweight protection
I installed a medium size of this back protector in the zippered pocket of a Vanson leather jacket, also size medium. It doesn't fit the pocket well (too loose), but it wasn't made for this jacket either. Nevertheless, it doesn't move around while riding. After a couple of rides, I literally cannot tell it's there anymore. It doesn't affect comfort at all. My jacket has zippered airflow panels, and the back protector does not impede ventilation. I recommend this to anyone who wants the extra peace of mind of added spine protection.
June 11, 2015
Ride:
2009 Buell XB12Scg Lightning
Bang For The Buck
4 / 5
Protection & Durability
5 / 5
Comfort
5 / 5
Style
5 / 5
Air Flow
5 / 5
Unnoticeable noticeable protection
Fits perfectly in both my Alpinestars textile and leather jacket. The only time I noticed the back protector was the first time I inserted it in the jacket, simply because the stock insert is soft and mushy. Air flow is fantastic. I'm riding in 75-85 degree weather and it adds no discomfort.

I can't say whether or not it actually works, fortunately, but it does add peace of mind in case I go down.

Trying to think of anything realistically negative about the product but nothing comes to mind.
October 12, 2015
Ride:
1997 Yamaha XV535 Virago
Bang For The Buck
5 / 5
Protection & Durability
5 / 5
Features
4 / 5
Comfort
4 / 5
Style
5 / 5
Air Flow
5 / 5
Great price and definitely addd a sense of protection.
Bargain priced, CE rated protection. Doesn't get any better
September 15, 2015
Purchased
over 2 years ago
Ride:
2012 Ducati Monster 796
Bang For The Buck
5 / 5
Protection & Durability
4 / 5
Features
4 / 5
Comfort
5 / 5
Style
5 / 5
Air Flow
4 / 5
Very worth it to have your back protected
I got this back protector to be used on the GP plus Air perforated leather jacket and it fits good. I don't even notice that the back protector is on there when you wear it. Little price to pay for some good back protection. I would recommend this to anyone.
October 5, 2015
Ride:
2013 Honda CBR600RR ABS
Start typing your question and we'll check if it was already asked and answered. Learn More
Browse 28 questions Browse 28 questions and 72 answers
Why did you choose this?
RevZilla Store
Does what it is supposed to do better than most.
J N on Oct 4, 2017
It fits in my alpinestars Andes v2 Drystar Jacket
Jeremiah T on Aug 30, 2017
Does what it is supposed to do better than most.
J N on Oct 4, 2017
Wanted to improve the protection of my leather cold weather and my Textile warm weather AStars jackets. Definitely worth the $$$
Robert K on Sep 13, 2017
It fits in my alpinestars Andes v2 Drystar Jacket
Jeremiah T on Aug 30, 2017
Recommended in review of Oxford Estoril Air 2.0 jacket that I recently purchased - Thanks!
Paul S on Aug 17, 2017
needed more back protection
Jack R on Aug 4, 2017
I have an Alpinestar jacket and wanted more protection
Christopher R on Jul 29, 2017
I wanted the best protection possible from my A-Stars Jacket
Brandon U on Jun 24, 2017
Goes with the jacket. Anthony uphold me with his video.
john D on Jun 22, 2017
extra protection. Brand
Jianping L on Jun 22, 2017
Fits the A-star GP Plus R
Steven R on May 29, 2017
This fits into the back of my Alpinestars Durban suit as an upgrade
Daniel D on May 23, 2017
great for ice-blocking down hills
Mark A on May 20, 2017
Improved safety
Victor B on May 19, 2017
... because it is what fits into my jacket.
Michael L on May 16, 2017
It goes into the jacket I just purchased.
Ryan L on May 8, 2017
Extra Safety
Enrique V on May 7, 2017
good protection
Philip C on May 6, 2017
Works with the jacket I bought
C A on May 6, 2017
Technical specs plus it will match the gp plus Leather jacket i have
Rey Nicolas T on May 5, 2017
Forgot to order it when I bought my vest at the cycle gear shop in Orange Park FL. The seller forgot about it too ...
Sebastien F on Apr 25, 2017
Chose this product to go with the ALPINESTARS JAWS LEATHER JACKET
A C on Apr 19, 2017
extra protection
john h on Apr 5, 2017
I've been hit head on by a car before and I know what good back armor can do.
Marc W on Mar 28, 2017
Wanted some decent back protection for my Brera jacket
John M on Mar 19, 2017
Added protection
Thomas C on Mar 12, 2017
style an protection and decent pricing
Dean M on Mar 8, 2017
Reviews and wanted that better protection in my jacket.
Eric S on Mar 7, 2017
most protection and best combo of technology
dani w on Mar 5, 2017
Looked like the best protection with airflow.
F A on Feb 22, 2017
Looking for added protection in my A* leather jacket.
William N on Feb 19, 2017
Highly recommended, upgrade from lower model for greater safety for just a few dollars more.
Gregory Y on Jan 12, 2017
Great protection capability rating plus its made specifically for the Valparaiso 2, which I have...
Sean B on Jan 12, 2017
Better protection than 2i for only 20 additional dollars.
Griffen R on Dec 29, 2016
Honestly... My wife insisted that I upgrade my back protection after the salesman at a local dealership brought it up when I was trying on gear. I've thought about it a lot over the past 2-3 years but it always just seemed like money that I could spend elsewhere on my bike to make me happier. As I age, my safety seems to be more important to me, and I'm sure I'd have ordered one soon without the loving nudge.
Anthony B on Dec 16, 2016
Best protection for my wife's jacket. She feels better protected than having the standard jacket pad.
Alex L on Dec 10, 2016
It fits my jacket and offers good protection.
Daniel H on Nov 25, 2016
It will fit the jacket.
Virgil J on Nov 15, 2016
safety is first
Jorge R on Nov 10, 2016
Safety first
kimbo f on Oct 15, 2016
I wear all alpine stars gear
Francis Y on Sep 15, 2016
The insert that the jacket comes with is just a place holder from this superior protection, when I went down my first time I was thankful I was wrapped in CE rated gear under my alpinestar GP-R leather jacket, walked away unscaved, invest in your life, it's worth it!
Jonathon D on Aug 17, 2016
Added protection. I need my spine.
ChuckRep on Jul 26, 2016
never can be to protected
P B on Jul 26, 2016
To protect my back, insert it in my Alpinestars GP Plus Jacket
James H on Jul 9, 2016
Just bought the blacked out Alpinestars T-GP Pro Textile Jacket and wanted that extra protection
H M on Jul 8, 2016
necessary
Eric J on Jul 1, 2016
Wanted high end armor for my new Alpine T-Jaws Air Jacket.
J O on Jun 24, 2016
want to protect my spine in event of a crash
Joshua L on Jun 22, 2016
Just to get a litle more from the jacket.
Mark C on Jun 22, 2016
I always upgrade my jackets inner protection. This fits great and doesn't make my jacket bulky or awkward to wear.
Raul G on Jun 17, 2016
Wanted to improve the protection of my leather cold weather and my Textile warm weather AStars jackets. Definitely worth the $$$
Robert K on Sep 13, 2017
Recommended in review of Oxford Estoril Air 2.0 jacket that I recently purchased - Thanks!
Paul S on Aug 17, 2017
What are the measurements of this Back Protector? Does it need be same size as foam insert?
Kenneth S on Jul 2, 2016
In the video review, Anthony says it only transmits 6kN or energy to the body. How does this compare to the new Forcefield Pro Lite K Back Insert?
John O on Feb 19, 2016
BEST ANSWER: I can't speak of the lite but I know the Forcefield sub 4 is below 4kN
Can i use this insert with a Joe Rocket Phoenix Ion jacket?
A shopper on Jul 16, 2015
Will this work with old Alpinestars CELER Jacket? Is the Nucleon KR-R better for leather jackets that have snaps?
A shopper on Sep 24, 2015
can i use it in my dainese alien jacket ?
Tony P on Apr 6, 2015
BEST ANSWER: Yes but the Dainese insert is better.
Will this insert fit the joe rocket ion jacket?
A shopper on Jul 16, 2015
My jacket has "comfort foam" where the insert goes, does this replace the foam? Or does it go in the pocket with the foam?
Michael H on Feb 11, 2016
BEST ANSWER: Yes, this replaces the foam. This will give full protection for your back on impact and sliding in case of an off.
Will this to fit into Dainese Hydra Flux D Dry?
A shopper on Jul 25, 2015
BEST ANSWER: I just compared this in a store and the large really close to the Dainese Manis D1 G2 insert (that Dainese's CE Level 2 back protector insert, in the larger of its size options).
Can it be used in the Textile Reaver jacket by Icon to upgrade the level 1 D30 armor to level 2 protection?
A shopper on Sep 20, 2016
Will this fit in my Alpinestars GP Air?
John M on May 14, 2015
BEST ANSWER: I believe it's supposed to fit with all A* jackets that accept an insert. I have an A* TZ1-Reload Jacket, which is an older model jacket than those out the same time this insert dropped and it still fit perfectly.
58 Customer Reviews
58 5/5
Read All Reviews
28 Questions & 22 Answers
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