Originally Posted by
TallRider
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My question is a bit different though - I was unsure if Sun extrudes two versions of the CR18 rim.
If the eyeletless version of the CR18 is the same extrusion as eyeletted, then the eyeletless rim will be more prone to cracking at the eyelets, and should probably be built with nipple washers at least. (That said, I realize the CR18 is a fairly strong rim.)
IME - nobody uses different extrusions for eyelet and non-eyelet versions of the same rim. I've always found that the model name defines the extrusion used.
So, if a rim is offered in both versions, the maker is saying that the non-eyelet version is OK, and the eyelet version is somewhat stronger (or more tolerant of stouter spokes or higher tension).
When selecting rims, I may set a lower max tension, or max gauge on the non-eyelet version. If I felt I needed washers, I'd probably simply buy the eyelet version in the first place.