Hunt Wheels Freehub Wear

Shimano splines are very small, designed for steel and now manufactured in alloy by aftermarket manufacturers, which just builds in problems. Campag splines are much chunkier as they were designed for alloy from the start. And that's one solution if you're running 11 speed, replace both freehub and cassette with a Campag one, they work perfectly with a Shimano or Sram 11 speed setup and you don't get the notching problem.

Happens with hope hubs as well, but hope do sell a steel freehub, if you're prepared to sacrifice a little weight for something more durable.

I always thought the larger sprockets are on carriers to reduce weight/cost and not to distribute load. Otherwise why not the smaller sprockets as well?

Arguably the smaller sprockets apply less torque to the freehub, but still sufficient to damage the hub

Aluminium is not a great material for withstanding the torque that comes through the cassette and excessive damage will occur if the cassette is loose, obviously.

That said, not all cassettes are created equal.  The more expensive a cassette is, the more spider arms it has.  These are mechanisms that both reduce cassette weight and distribute load more evenly. Dura Ace and Ultegra cassettes have five cogs on two spiders, whereas an 11-speed 105 cassette has only three cogs on one spider, meaning that there are more single cassette splines interfacing directly with the freehub and chewing it up..... but I'd stick to Fulcrum wheels if I were you.  They won't cheat you with unsuitable materials and selling it to you as a weight saving!

I understand how maintenance can vastly improve bearing life, but how can maintenance prevent the sprockets from digging into the splines? I find it hard to imagine that any reasonable amount of torque on the locknut will create enough sprocket-to-sprocket friction to prevent this. You can produce at least 100 N-m torque on the sprocket when pedaling.

Better freehub bodies have at least one steel spline to prevent this. Apparently Hunt's don't.

On the other hand, I bought their Adventure Disc 650B wheelset last year, and it's still going great after more than 6700 miles, including a real winter (midwest USA.) I'm still on my first cassette, so I'm hoping not to find mine looking like that when I go to replace it.

What post-purchase maintenance do Hunt recommend? Might be worth asking the question, and check that you were informed of the maintenance schedule when purchasing.

50 Nm is a lot for a bike torque wrench, and for a spanner. I tighten my cassettes to a precise "pretty bloody tight" with a socket and tommy bar. Should I be checking every X km?

Normal wear and tear. Starting to see hubs on some wheels with a steel bite guard insert, including some of the Hunt wheels. £30 is reasonable for a freehub too