Originally Posted by
TandemGeek
Good policy when it comes to machines. Seriously, if you or anyone else has not had any problems with their Calfee eccentric then keep-on keepin' on.
As I said, it's not a poor design and not everyone has problems with them. The newer version should be even less prone to problems because of the things I mentioned earlier regarding better 'bite', better compatibility with the newer oversized bottom bracket designs and more robust bolts. In fact, the Calfee eccentric is ideally suited for the newer bottom brackets given how they tend to work (compressing against the eccentric when torqued) compared to the older types of Square Taper, Octalink and ISIS BB's that tend to work against the Calfee eccentric (pushing outward from the center of the eccentric as they are torqued).
The latter is what I encountered given my use of Phil Wood tapers and that's where the Bushnell begins to shine. Like most other eccentrics, the Bushnell is build around a solid core into which the eccentric is installed. So, unlike the Calfee eccentric that can only be removed from the frame after you've removed the bottom bracket, the Bushnell allows you to remove the eccentric and bottom bracket as a single unit by simply removing one of the crank arms:
It also allows for the use of a closed eccentric shell and then fills the entire void as it's tightened to form a tight fit around nearly the entire circumference of the shell.
But, as I said at the outset, your philosophy is sound: If it ain't broke, there's no need to fix it.
TG, that Bushnell is obviously a nice item, and has made our list of future items for our Co-Mo.
I am curious though, many of the recommendations posted tend to point towards contacting the oem for a solution. In regards to installing an expansion type eccentric into a carbon bike, even though yours now has an insert, what was Calfees thoughts on possible disbonds occurring in the local area of the Bushnell wedge? The oem Calfee design utilizes a compression concept which is normally preferred in composite structures. Expansion designs, can cause issues with composites, just curious if they endorsed the Bushnell and will warranty any disbonds or related issues after not using the Calfee eccentric.
Not a rant nor attack, rather a curiosity about how they viewed this. Myself, as a composites guy, have some guidelines we tend to try and adhere to, one of which is minimizing stresses to create other possible failures, typically delaminations and disbonds. Obviously the answer is I could call them myself, but we know that won't happen as it's not that important to me.
PK