Lightning Bolt-on Axle – Front 15 mm x 155 mm x M14 x 1.5 Thread

(16 customer reviews)

$ 42.00$ 48.00

After years of mountain biking with bulky-handled thru axles that seemed to strike every trailside obstacle, we needed a better option.

Our Lightning Bolt-On thru axles offer the highest quality, simple, lightweight alternative to that bulky handle. Available in a range of sizes that fit both front and rear wheels on all types of thru-axle equipped bikes. Compatible with Hexlox security systems. These axle fits Fox Forks with 15 x 110 BOOST hub spacing.

We offer two variations:

  1. 2021 and newer Fox 36 and 38 forks feature a floating axle design. ONLY if you are replacing the Fox Kabolt bolt-0n axle with our bolt-on axle will you need LIG504.F which includes a floating shim.
  2. For all other 15 x 110 mm Fox forks you will need LIG504
Get 20% Off Lightning Bolt-on Axles With Purchase of Any Trailer or Trainer Axle! Discount Automatically Applied.
SKU: LIG504 Category:


  • Lightning is Better. Our front and rear Lightning Bolt-On axles offer a stronger, more durable, lower profile and lighter weight option to replace your stock thru-axles.
  • Low Profile. No more bulky handles to strike trail obstacles or create wind drag. Aerodynamic design.
  • Light Weight. Our axles are internally bored to remove unnecessary material without compromising strength.
  • Easy to install. Our matching front and rear Lightning Bolt-On Axles only require a standard 6 mm hex wrench for easy installation and removal.
  • Better Tolerances. Manufactured in the USA to the tightest tolerances using aerospace materials and CNC manufacturing. No longer will your axle loosen while riding.
  • Available Security. Learn about compatibility with Hexlox bike security systems.

This is NOT an axle for attaching trailers or trainers.


Prop65 Warning icon

WARNING: This product can expose you to chemicals including nickel acetate, which is known to the State of California to cause cancer. For more information, go to

Additional information

Weight N/A
Select Your Fox Fork

LIG504.F (Axle With Shim), LIG504


  • This axle fits Fox Forks with 15 x 110 Boost hub spacing
  • The diameter of this axle is 15 mm and the true length of the axle shaft is 155 mm. Please note: Thru-axle lengths do not equal hub standards. An axle has to be longer than the hub to fit in the frame. A 15×100 hub does not equal a 100 mm long axle.
  • This axle has a M14 x 1.5 mm thread pitch.
  • Weight: 53 grams
  • The axle is precision CNC machined in the USA from 7075 aluminum and hard anodized for rugged durability. Our axles are built to the tightest standards in the industry.
  • No special tools required. Design allows for installation or wheel removal using your standard 6mm hex wrench.
  • Designed, built and quality tested in the USA. Proven around the world.
  • Learn about compatibility with Hexlox security systems.


Need more information about how our axles work?

16 reviews for Lightning Bolt-on Axle – Front 15 mm x 155 mm x M14 x 1.5 Thread

  1. Jim Chapman (verified owner)

    followed the options on the fitment selector and used the thru axles for both front and rear on my new mtn bike. Worked perfect.

  2. Ted P. (verified owner)

    Fits just perfect! Wonderful customer service and assistance. In conjuction I am also using the HexLox security system. Great partnership. I no longer have to carry a security cable to leash-up wheels, etc.

  3. Larry (verified owner)

    Excellent communication and perfect on the SB5.5

  4. Derrick M. (verified owner)

    Replacement for stock Fox QR axle on my Fox 34 15×110. Beautiful, US machined, piece of equipment. Order with confidence.

  5. Drew Chilson

    Excellent. Nicer machining & finish than all the others. Simple, clean, light. Bonus points for amazing & friendly customer service.

  6. Mark (verified owner)

    Bought this for my 2017 Trek Top Fuel 8.
    Made in the United States of America.
    Bolt-on piece of mind.
    No more gigantic QR levers sticking off my bike.
    No more fighting with QR levers to release/tighten them.
    No more deciding which direction looks coolest and is safest when closing the QR levers.
    No more banged up QR levers detracting from the look of your bike.
    Mega fresh appearance.
    Everyone is jealous.

    This is an excellent though subtle upgrade that should definitely be the second thing you do to your brand new bike (after a fitting). I check them with a torque wrench before I leave my house for a ride so that there is never anything to worry about. That being said, they haven’t loosened at all since I’ve installed them about 60 miles of vicious trail riding ago. Buy these.

  7. Stephan Kincaid (verified owner)

    Stoked on this upgrade! No more bulky thru axle release handle. The Robert Axle is high quality and beautifully made.
    I’m very pleased with the product quality and customer service of Robert Axle.
    Rock On!

  8. Eric Steinberg (verified owner)

    There couldn’t be a more helpful site to solve your axle search than what they have on the site here. Also great response time and a great product. Highly Recommend.

  9. Allan (verified owner)

    Great product. Looks good too. Need to get the rear axle to match the front.

  10. Jeffrey Baker (verified owner)

    Bought this axle for my 2019 Pivot Mach 6. Excellent part! Would 100% recommend! Well worth the money!

  11. Jon (verified owner)

    Another awesome product from Robert Axle Project! This was a perfect replacement for my Fox 15×110 Boost spacing TA on a 2017 SC Tallboy. Love that it’s lighter, made in the USA, supports a small company, has a cleaner look, and I can torque it to a spec. This company rocks!

  12. Sean

    So far so good. Love the sleek look and not having the QR. Love the axle selection helper!!

  13. Ted Carmichael

    I have a 2017 Kona Honzo, and the first upgrade I ever did to it was a RAP rear axle after so much frustration with the stock thru-axle. Now many years and upgrades later, I need a front axle for my new Fox 34. There are several options including Fox for a bolt-on front axle. However after absolutely loving my rear axle and it’s custom fit for so long it was a no-brainer to go with Robert Axle Project once again.
    The machining is second to none, the fit is perfection, and it’s actually made here, what more could you want? You simply need to torque these axles to 12 Nm and your brakes are spot-on every time.
    I cannot recommend these axles enough, if I had 1000 thru-axle equipped bikes, I would buy 2000 of these.
    Thanks RAP

  14. Marcial Bacani

    Replaced original QR axle that came with the Yeti/Fox 36. Glad I did it. Fine product. Nice fit and finish.

  15. Brandon M (verified owner)

    Replaced my QR on a Marzocchi Bomber MTB fork for peace of mind. The fit, finish, weight and quality are top notch. Threaded in perfectly, the 6mm hex hole is nice and deep, allows a wrench to go in far enough that you won’t have to worry about it slipping out and galling or stripping anything. Doesn’t come with a washer like most I’ve seen, but a little squitz of grease where it touches might prevent any potential scratching. That’s the only issue I have is no washer, but I’m probably overthinking it. Great Axles! Bought one for the rear as well just so they’d match.

  16. John Sengelman (verified owner)

    Easy to use website is helpful. Axle shipped quick and is well made and perfectly functional. Thanks so much!

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