I received a Racing Zero Carbon from a customer.
It's been used quite a bit,
but there's no runout—it looks fresh off a truing stand.
The front hub had a new shaft that was about to catastrophically fail, so
I just took care of that.
When I applied a 5mm Allen key to both axle ends, the right side loosened first,
so I applied a strong thread-lock compound and tightened it solidly
with a 14mm wrench and 5mm Allen key.
Next, using a 14mm wrench on the right and 5mm Allen key on the left,
I loosened the left end, applied grease to the threads,
and tightened it just enough so it won't come loose.
I immediately checked with 5mm Allen keys on both sides
and confirmed the left loosens first (as shown above)—
I think this should prevent the right end from loosening in the future.
It's been used quite a bit,
but there's no runout—it looks fresh off a truing stand.
The front hub had a new shaft that was about to catastrophically fail, so
I just took care of that.
When I applied a 5mm Allen key to both axle ends, the right side loosened first,
so I applied a strong thread-lock compound and tightened it solidly
with a 14mm wrench and 5mm Allen key.
Next, using a 14mm wrench on the right and 5mm Allen key on the left,
I loosened the left end, applied grease to the threads,
and tightened it just enough so it won't come loose.
I immediately checked with 5mm Allen keys on both sides
and confirmed the left loosens first (as shown above)—
I think this should prevent the right end from loosening in the future.