thru axle finder

Our Thru Axle Finder Guarantee

Robert Axle thru axles are designed and made to fit YOUR bike and YOUR needs! That’s why we have created this handy Thru Axle Finder so you can find the exact axle you need. When you use the Fitment Finder, we guarantee the result of the Finder, 100%.


For Bikes with the Naild Thru Axle System

Currently, some Marin, Argon 18 and Polygon bike have the proprietary Naild thru axle system. Our thru axles replace your Naild axle for a simpler, more durable option. All axles come with a threaded nut.

bol-on replacement naild axle

Lightning Bolt-On Axles

Replace your rear 12mm Naild thru axle with a simpler, more durable Lightning Bolt On Axle. This axle only takes a 6mm hex wrench found in any multi-tool and come with a replacement nut, for easy installation.


Front Naild Replacement Thru Axle for 12×100 – LIG506.N

Front Naild Replacement Thru Axle for 15×100 – LIG516.N


Rear 12mm Naild Replacement Thru Axle for 12×142 – LIG603.N

Rear 12mm Naild Replacement Thru Axle for 12×148 – LIG613.N

Naild thru axle for trainer

Trainer Axles

Our Naild Trainer Axle axle allows you to use your Naild axle equipped bike (such as Marin, Argon 18 or Polygon) on a wheel-on resistance trainer.

Trainer Axle for Naild bike with 12×142 – TRA217.N

Trainer Axle for Naild bike with 12×148 – TRA213.N

naild thru axle for attaching trailer

Kid Trailer Thru Axles

Attach any “hitch-style” trailer (Chariot, Burley, Thule, etc.) to your bike that has Naild thru axles. Easy to install, durable and strong enough to carry your precious cargo.

Kid Trailer Axle for Naild bikes 12×142 – KID217.N

Kid Trailer Axle for Naild bikes 12×148 – KID213.N

Naild axle for attaching BOB Trailer

B.O.B. Trailer Thru Axles

Attach your trusty B.O.B. Trailer to your Naild thru axle equipped bike!

B.O.B. Trailer Thru Axle for Naild bikes 12×142 – BOB117.N

B.O.B. Trailer Thru Axle for Naild bikes 12×148 – BOB113.N

Legal statement of the obvious. These are not Naild thru axles, but they are a durable and easy to use replacement. Our goal is to produce a solution for bikes such as the Marin, Argon 18 and Polygon. No permanent modification is required of your bike. At any time you can return your bike to using the Naild thru axle by simply reinstalling the Naild nut and thru axle that came with your bike. All trademarks of Naild are respected.

The Robert Axle Project

All axles are proudly made in
Bend, Oregon

[email protected]

About Robert Axle Project

We like to say that we are the Thru Axle Authority. Not like police style authority, but more like, we know our stuff when it comes to thru axles. That’s why, when you’re shopping for a thru axle, if you use our Axle Fitment Finder we guarantee the result, 100%. If for any reason you use our Axle Fitment Finder and it takes you to the incorrect product for your bike, we’ll exchange it for the right axle at no cost.

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