On some headsets which use a cartridge bearing in the lower assembly, the crown "race" is split. Also, I know a lot of people split their crown race for the ease of installation.
Perhaps I'm overly concerned, but I'm wondering about two things.
- Has anyone ever cracked a crown race during use? If this is something that can happen, a split crown race might shatter into pieces..
- The crown race is held somewhat snug by the chamfered edge of the bearing, which suggests it might prevent a broken crown race from falling of the fork. Has anyone ever crashed due to the crown race / lower headset assembly failing?
Edit: I ask this because I consider splitting a race. I'm switching out a RS Reba for a Surly 1x1 fork, both of which have a crown seat diameter of approx. 30mm (as do all 1.125" forks, as far as I know). I tried setting it using my "specialized race setting tool" (i.e. some PVC piping and a mallet) and plenty of lube. No luck however, the pipe started to shatter but the race wouldn't set :-(. It seems like the seating is just a hair too wide for the race to seat. As far as I see there are two options: file down the crown seating a bit, or split the race. The latter seems easier; also I'd rather modify a 3€ part than a 50€ one. But only if I won't loose my teeth over it :-P.