Nox Composites AM 275 650B carbon fiber mountain bike rimTennessee-based upstart Nox Composites has their new AM 27.5″ carbon rims ready for production, and they’re offering a pre-order deal of $399 per rim for early customers.

The rim has a 27.5mm internal width, 35mm outer width and 25mm depth. Like their others, it uses a mix of UD and woven Toray carbon fibers of varied modulus to make a rim that’s both stiff and durable. And light. Claimed weight is just 415g. They’re shaped with a rounded center groove to ease tire installation with a small bump to then help the bead settle into the hook and stay there.

We’ve been testing the 29er XC rims and have been very impressed. Regular price is $475 per rim, so you can save $150 per pair by ordering soon. Original deal deadline was December 13, but they’re extending it until they fill a production run’s worth of orders. Details and more tech specs on their website.

Also available as wheelsets with either Chris King, Industry Nine or American Classic hubs, all built with Sapim CX-Ray spokes. 32 and 28 hole drilling options.


  1. Aren’t these the wheelbuilders who didn’t know how hub/spoke bracing angles worked?

    The rims aren’t made in Tennessee either, they’re from China.

  2. That’s cool, that’s cool…but WTB KOM rims can be had for $90 each at 410g…that way you won’t sh*t yourself if you ding your rim during a ride.

  3. True- but the WTBs are only a 23mm outside width. Not even close to the same rim, so ymmv if you are hoping they would be a comparable alternative. Something like the Syntace W35 MX would be a closer alternate- and yet, check the price on those….

  4. From WTB’s website:

    “To put things into perspective, a KOM i23 (the i23 stands for internal 23mm) in 29” flavoring tips the scales at a mere 426 grams.”

    Their i25 weighs in at 512g. Heavier for sure, but they only cost $49…..

  5. There’s so much more to it than weight. Carbon rims improve lateral stiffness so much it’s crazy. If you are riding fast and pushing the limits in chunk and corners, stiffness will make you much faster than saving a few grams ever will.

    They sure as heck seem to know their wheel building stuff to me

  6. While I somewhat agree with the ‘lateral stiffness’ issue, I would reckon 90% of riders could not notice any discernible difference in a blind taste-test. I’m sure NOX makes good stuff, and the price is very fair. But this rider will be sticking with alloy for now.

  7. ^^Most people will absolutely notice the difference in stiffness. It’s not slightly better, it’s waaaaaaay better. Yeah, alloy is still the best bang for the buck though. But if you got the dough, good carbon is great.

  8. Oh ya, alibaba is the first place I go when looking for quality bike parts I won’t die on. good lord, you people would buy a carbon wheel my 4 year old niece made in her easy-bake oven if it was cheap enough.

What do you think?