Log In / Register
Cart (0) Checkout
Alpinestars Nucleon Back Protector Insert
Zoom
  • Alpinestars Nucleon Back Protector Insert
  • Alpinestars Nucleon Back Protector Insert

Please select a Size to check availability, or to add this item to your Shopping Cart or Wish List.

Select Size:

Size Chart
Select qty:
Your Price
$49.95
Please select a Size to view availability.

Video Review

Alpinestars Nucleon Back Protector Insert Videos

Alpinestars Nucleon KR-2i Back Protector Insert

Features:

  • CE Certified Level 2 (EN1621-2:2014)
  • Lightweight, flexible PU injected impact foam
  • Contoured for anatomical and adaptive fit
  • Perforated for breath-ability and comfort
  • Channel ventilation system for optimized airflow

Note: Size MD is recommended for Men's jackets size 50 and smaller and XS-MD. Size LG is recommended for Men's jackets size 52 and larger and LG-4XL. See specific Women's jackets for sizing recommendations.

Sizing Info:

Waist to Shoulder (in) Height (in)  Protector Size
15 - 17 56.75 - 64.25 SM
17 - 19 64.25 - 71.75 MD
19 - 20 71.75 - 76.5 LG

Write a Product Review for a chance to win our monthly $100 giveaways.
Alpinestars Nucleon Back Protector Insert 5 5 14 14
Its your back! Who doesn't want to protect your back? Fixing up bikes can be fun, but don't neglect yourself. You deserve to walk away. March 3, 2015
Love it Nice and light in my Alpinestars Celer! Fit is just right February 13, 2015
save my life Bought this product two months ago. I recently had a motorcycle accident going like 60mph in the canyons, it observer all the impact of me hitting the floor and save my back from breaking, I believed it save my life. I will surely buy this product again. January 21, 2015
Don't think, buy Level 2 certified. Breaths extremely well. Cheaper than most others. Enough Said January 10, 2015
This back protector is a great value. The new A* back protector is awesome. It feels like a solid piece, though I hope to never find out how it performs. The price is great and the fit is perfect. January 7, 2015
cheap, and gets the job done Bought it in a medium to fit my medium a stars jacket and it fits perfectly. Light and low profile but feels very strong. Hope I never have to 'test it out" but I feel a good sence of security with it. I highly recommend you upgrade that padding to this back protector January 5, 2015
did the unthinkable and used it on a non alpinestars jacket!! I wanted a higher level of back protection for my icon jacket i use for commuting to work and around town. I found this alpinestars nucleon and saw the review on youtube. Needless to say seeds were planted and i recieved it for Christmas! !! Thanks santacycleclaws!!. My family member ordered a size medium off the alpinestars chart and and upon putting it in my icon jacket it was about 2 inches short. Luckily my girlfriend is a master seamstress (thats a joke but shes good) she hemmed up the lower portion of the back protector pocket so that the back protector is in the correct place as illustrated on the back of the nucleon package and took out the extra slack. All is well. It forms to the body and is relatively light weight. It breaths well and does appear to have a good amount of protection. I cant speak for an actual crash but i did have my girlfriend kick me a couple times in the back and it felt like a gentle massage. Great product and thanks again revzilla . If you are going to put this in any icon or similar jacket i would recomend getting the large version although the medium worked ok with small alterations. by my measurement the large nucleon will be about 1 inch shy being 18 in in length by 10.5 in wide . The icon stryker style foam pad was 19 in in length and 10.5 in wide just for reference if anyone is thinking about doing this. The medium nucleon is 17 in long by 10 in wide . Some may think it's taboo to mix and match brands like this however i like my jacket and i like what alpinestars is doing here so i went with it im sure i wont be the only one who will be doin this. December 27, 2014
Great Upgrade I bought a great A-star jacket here and wanted to upgrade the back protection. Noticed this product had just arrived at REVZILLA and that it was actually less $$ than the model it replaced. Purchased a Large for a 52 jacket. December 15, 2014
2 next>>
Use our Product Q&A for a chance to win our monthly $100 giveaways.

Have a functionality, fit, or otherwise product-specific question about the Alpinestars Nucleon Back Protector Insert? Ask it here! If you have a customer service or shipping question, please direct it to our Customer Service department.

Alpinestars Nucleon Back Protector Insert
Already Asked: 12 Questions, 55 Answers
Sort by:
RevZilla Store asked: Why did you choose this?
Michael B: My back is important to me and more protection is better than less and for the price and reviews it was an easy add on to the jacket I just bought. Mar 4, 2015
Kahaa R: I own a Alpinestars T Jaws Jacket and would like to add extra protection to it. Feb 28, 2015
B R: Your video and Raina's outstanding assistance. Feb 27, 2015
Fares Y: Well reviewed Feb 20, 2015
William L B: I bought a large 2013 Alpinestars Megaton jacket and am 6'1". The foam pad that comes with jacket offers very little if any protection. This back protector seems like a great deal for class 2 CE back protection. Feb 19, 2015
Maxime V: Perceived quality, Protection Level, Revzilla video review & reputation, people's review, Price, brand equity. Feb 17, 2015
K S: Price. Feb 16, 2015
Pride A: I chose this because it fits the jacket I ordered, as well as its level of protection and reasonable price. Feb 11, 2015
johnathan b: Best protection for a back insert by far Feb 8, 2015
Juan J G: Cheaper and newer and a higher protection rating than the bionic air back protector. Now im waiting for the new chest protectors to come out Jan 14, 2015
Chuck D: I purchased this for my Alpinestars Andes Drystar Jacket and it feels and works great. This newer back protector is less expensive and made better than the older version. Dec 27, 2014
Francis R: Intermediate protection for a sportrider. Very pleased with the design and air flow. Good bang for the buck! Dec 18, 2014
Neil H: Protects my back better than the foam insert that came with my jacket. Dec 13, 2014
Michael B: I got my back Dec 2, 2014
Francis A: review on revzilla and flexibility and wt. Nov 28, 2014
Lawrence W: Much needed item to match the jacket. More added protection. Great price and good reviews. Nov 23, 2014
Dylan F: to beef up my a* jacket Nov 22, 2014
Robert H: The price and protection. Win Win for me... Nov 9, 2014
Sandra F: For CE certified level 2 back protection in order to replace the foam piece that comes with the motorcycle jacket. Oct 29, 2014
Joaquin F: Wanted improved back protection for my Alpinestars Celer jacket. Oct 13, 2014
William K: Anthony's review, of course! Oct 6, 2014
Yang L: For best protection against high impact area. Sep 30, 2014
Anthony D: Upgrade to the AStars Celer jacket I just bought. Bionic armor is level 1 and $30 more. This looks to be a win, hopefully it fits and performs as well as all other Astars gear. Sep 25, 2014
caleb s: so i can have protection Sep 23, 2014
katsuhide y asked: Which size d I need to get for my alpinestars small TGPR texture jack ?
I'm confused Your video says Dont get small size?

Thx
Feb 1, 2015
Answer this · Send to friends Good question? Yes (1) No (0)
Jim T: I got a Large for a size 56 jacket. Feb 1, 2015
Reply to Jim Good answer? Yes (0) No (1)
katsuhide y: Thanks Jim.
I called Revzilla.

Size Small protector for women's jacket.
Size medium protector for men's small and medium jacket. Feb 2, 2015
A shopper asked: I have an Alpinestars GP Tech Air Jacket in size 48. I'm unsure on which size back protector to get. I'm roughly 5'6", 150 pounds. Which size is right for me? Dec 29, 2014
Answer this · Send to friends Good question? Yes (0) No (0)
Chris M: Probably Medium. I'm 5'7" 162 and have a Medium in my M Bogota. Feels great. Ironically, I don't even notice it's there, which I guess means that it "feels" great! Good luck. Jan 13, 2015
Reply to Chris Good answer? Yes (0) No (0)
Timmy H: I have an Alpinestars GP Plus Leather Jacket size 52 and the Large barely fits for me. Most likely the medium will fit for you as the large is recommended for sizes 50 and up. Jan 13, 2015
Reply to Timmy Good answer? Yes (0) No (0)
Richard Z: According to video, size medium/50 or smaller go with medium. Size large/52 or greater, go with large.
I have a xxl Alpinestars TGP-R air jacket and the large fits fine
Jan 13, 2015
Reply to Richard Good answer? Yes (0) No (0)
Scott T: ok I went by what Antonio advised in the video. med size for jackets 50 and below and lg for 52 and up and it fit perfect in my jaws wp jacket hope that helps ya Jan 13, 2015
Reply to Scott Good answer? Yes (0) No (0)
Slav S: Go with a medium. It will be the correct size for your jacket according to the specifications on the back of the nucleon packaging. Jan 14, 2015
Reply to Slav Good answer? Yes (0) No (0)
Slav S: Go with a medium. It will be the correct size for your jacket according to the specifications on the back of the nucleon packaging. Jan 14, 2015
Reply to Slav Good answer? Yes (0) No (0)
Slav S: Go with a medium. It will be the correct size for your jacket according to the specifications on the back of the nucleon packaging. Jan 14, 2015
Reply to Slav Good answer? Yes (0) No (0)
AL J: To play it safe brother. Call Revzilla they will have your answer 100% Jan 13, 2015
Reply to AL Good answer? Yes (0) No (0)
A shopper asked: I am purchasing the Alpinestars Stella Gunner WP textile jacket in a size small. Should I purchase the Alpinestars Nucleon Back Protector in small or medium? I am 5'2" and weigh 110 lbs. I am also considering purchasing the Alpinestars Bionic Chest Pad, although I'm not sure how much protection the pads really offer.

I'm a new rider on a 2004 Honda Rebel 250CMX

Any suggestions are welcomed!
Oct 29, 2014
Answer this · Send to friends Good question? Yes (0) No (0)
Michael S: Hi - I am also a new rider (2014 Honda CB500f). I am 5'7" and 175 pounds and where a Large Jacket because of chest size. The protector is light and semi-flexible. I got a Medium and it fit fine. I think Revzilla has a return policy so I would go for a medium if you where a Medium jacket. If you where a small jacket, then I would get a small. That is purely my guess. You should contact Revzilla; they have been great about answering questions for me. Oct 29, 2014
Reply to Michael Good answer? Yes (1) No (0)
Sandra F: Thank you! Oct 29, 2014
Robert J: At 62" tall you should get size small in the Alpinestars Nucleon Back Protector. The women's model of the Bionic Chest Pads will definitely give you more protection and is highly recommended. Oct 29, 2014
Reply to Robert Good answer? Yes (1) No (0)
Sandra F: Thank you! Oct 29, 2014
William K: I'm thinking the small one. Measure the foam pad that came with the jacket and order the appropriate size listed on the chart on the Alpinestars site. Good luck. Ride safe. Oct 29, 2014
Reply to William Good answer? Yes (1) No (0)
Sandra F: Thank you! Oct 29, 2014
gregory k: I purchased the LG Im 6ft but my shoulder are bigger then the 20 (22) recommended. It seemed a little narrower then I expected. Putting it in the Alpine 3X Daystar ( I have a side to side gap of approximately 1"). Therefore, I think it is more dependent on the width then the length. So if you have wider shoulders I would go with the medium, if narrow I would go with the small. I'll check with my daughter who is 5'5 and see how it would fit. She just ordered a new jacket. Oct 31, 2014
Reply to gregory Good answer? Yes (0) No (0)
Rania M: Use this conversion for sizing:

Small is for Stella products only. (Ladies Only)
Med insert is for Med Alpha sizing or below, or size 50 and below.
Large insert is for Large Alpha sizing and higher, or size 52 and up.

Cheers!
Gear Geek- Rania
Nov 5, 2014
Reply to Rania Good answer? Yes (0) No (0)
Sandra F: Thank you! Oct 29, 2014
Reply to Sandra Good answer? Yes (0) No (0)
Sandra F: Thank you! Oct 29, 2014
Reply to Sandra Good answer? Yes (0) No (0)
brent b: Small Oct 29, 2014
Reply to brent Good answer? Yes (0) No (0)
A shopper asked: Hi there. I have an Astar Jaws leather jacket in a size 54. What a great step up from my Astar textile jacket!

I currently have installed an Astar back protector from my old jacket and it is 18 inches long and fits very well.

Can you please confirm that I need a LARGE Alpinestars Nucleon Back Protector Insert for my new Jaws jacket?

Mark@OZ - Suzuki SV650n
Nov 13, 2014
Answer this · Send to friends Good question? Yes (0) No (0)
Mark R: Oops! Manoj K has already provided dimensions - Large: 18"L x 10.5"W

Large it is!

Mark@OZ - Suzuki SV650n
Nov 13, 2014
Reply to Mark Good answer? Yes (0) No (0)
Sean R: Yes you need the large. That's the one I got and it fit perfectly in my Jaws size 54. Nov 13, 2014
Reply to Sean Good answer? Yes (0) No (0)
Craig P: I have 52 Astar GP Plus R Jacket and large fits fine. 52 and up is large. Cheers Nov 13, 2014
Reply to Craig Good answer? Yes (0) No (0)
Robert J: Large definitely. Size 52 and up take a large Nucleon. Dec 10, 2014
Reply to Robert Good answer? Yes (0) No (0)
A shopper asked: Hi,
Does anyone know if this back protector will fit into the Alpinestars celer jacket?And how it compares to the the bionic back protector?Cheers.
Feb 18, 2015
Answer this · Send to friends Good question? Yes (0) No (0)
Lawrence W: I purchased a mesh Alpine T-GP Plus Air jacket. The back padding was nothing to brag on so i purchased the Nucleon Protector. It was just an easy slip in. From reading up on the celer jacket this padding will fit as it is CE level 2. As far as comparison. The price is about half for one. The quality of the Nucleon is not of cheap material or design. It also allows for great circulation of air on the back area. I cant complain and i am very satisfied with the Nucleon. Plus for the price of the celer jacket it should come with all the protection u could hope for. If you do purchase either one and don't need it,as long as it's not open u won't have any problems returning the item. I had to return chest protection because the jacket did not have slip in spaces for them. Hope this reply was helpful. Feb 24, 2015
Reply to Lawrence Good answer? Yes (0) No (0)
Scott T: there are reviews that will answer your question and lv rating hope this helps ya Feb 18, 2015
Reply to Scott Good answer? Yes (0) No (0)
A S asked: I'm sorry if this is a dumb question, but why is this CE Level-2 back protector cheaper than the Alpinestars Bionic Air Back Protector Insert that is only Level-1? Is this one inferior is some way? Jan 25, 2015
Answer this · Send to friends Good question? Yes (0) No (0)
gregory k: I believe the manufacturing process makes it easier to produce Because I can tell you my kids are always worried about me so they took the protector and dragged it on the concrete with a weight on it, rolled over it with a skateboard, and rode over it with a bike. - NO DAMAGE - not sure it a valid test but they wanted to be sure it worked. Feb 13, 2015
Reply to gregory Good answer? Yes (0) No (0)
William K: I believe the bionic air may be a little more flexible and constructed differently. The Nucleon is a new one piece material and probably less expensive to produce. I went with the Nucleon since it was a good price for a Level 2. Feb 12, 2015
Reply to William Good answer? Yes (0) No (0)
A shopper asked: Does it fits the Dainese Air Crono Mesh Jacket size 52? Dec 10, 2014
Answer this · Send to friends Good question? Yes (0) No (0)
A s: Yes it should!! I have it in a alpine star jaws perforated leather and it is very comfortableand and for a level 2 back protector it is very affordable!!! Dec 10, 2014
Reply to A Good answer? Yes (0) No (0)
Robert J: Medium should fit. The size large is too long. May want to go with the Dainese G1 or G2 insert designed for your jacket. Dec 10, 2014
Reply to Robert Good answer? Yes (0) No (0)
Sandra F asked: I am purchasing the Alpinestars Stella Gunner WP in size small. I am 5'2" and weigh 110 lbs. Should I purchase the Alpinestars Nucleon Back Protector in size small or medium? Oct 29, 2014
Answer this · Send to friends Good question? Yes (0) No (0)
Manoj K: I would measure the foam one that it came with originally and get the same size. Hi-Viz Brian gave me the actual sizes of each pad and they are: Small: 15.5"L x 9"W......Medium: 17"L x 10"W....Large: 18"L x 10.5"W Oct 31, 2014
Reply to Manoj Good answer? Yes (6) No (0)
Sandra F: Thanks! Nov 3, 2014
Reply to Sandra Good answer? Yes (0) No (0)
Martin S asked: I have a Dianese Air 3 jacket (size 58) and think that this protector might be the best fit for the pocket shape.I think it may need to be trimmed a little for length. Anyone used this protector in the Air 3 jacket? Is this a good option? Jan 13, 2015
Answer this · Send to friends Good question? Yes (0) No (0)
Christopher S: Hi Martin,
I bought this one for my GP Pro Jacket also size 58, it fits as good as the previous one: Alpinestars Bionic Air Back Protector Insert, but I stick to the Nucleon One due to a better CE & protection, you should be fine with a size MD.

Hope this helps.
Jan 13, 2015
Reply to Christopher Good answer? Yes (0) No (0)
A shopper asked: I have a Dianese Air 3 jacket (size 58) and this protector looks to be the best fit that I can find, but may need to be trimmed a little for length. Anyone fitted this protector to the Air 3 jacket? Jan 13, 2015
Answer this · Send to friends Good question? Yes (0) No (0)
gregory k: I didnt trim and it fit just right. The internal jqcket velcro is snug and tight and does not dis-engage. In a disaster it should save your back. I tried just falling on or rather my kids did (my kids decided to tackle me) and no pain (the basic foam that came with the jacket ok. But figured it would hurt on a curb). Landed on lump on asphalt using the insert / knew the lump was there but otherwise no problem. Jan 14, 2015
Reply to gregory Good answer? Yes (0) No (0)
A shopper asked: Which size d I get for my alpine stars gtr air texture jacket small?
I'm confused that Your YouTube ads say don't buy small size.
Thx
Feb 1, 2015
Answer this · Send to friends Good question? Yes (0) No (0)
Product Style RevZilla Item # Manufacturer Product # Availability
SM 973533 6501615-10-S In Stock: Ships within 24 hours
MD 973534 6501615-10-M In Stock: Ships within 24 hours
LG 973535 6501615-10-L In Stock: Ships within 24 hours