Bump cranks? This thread is awesome btw.
Depends and I have been full OCD over all of this lately. You also need to pay attention to the bottom bracket you use. Really will not be able to avoid anything with a Ti spindle and aluminum cups with sealed bearings.
Another issue I have learned about with my recent acquisition of Grafton Speedstix is that while they are a very light crank set, the way they are designed requires a bottom bracket spindle upwards of 122 to 125 mm wide. So I win on the crank weight, but lose a little bit on the spindle length. Topline, who very early on made Grafton cranks are a tad lighter because the back of the crank arms are milled BUT also require anywhere from 122 to 132 mm wide spindle. Kooka's, Race Face Next LP's, Cook's, Cook Bros...all are a tad heavier than the Grafton's but also use a more traditional spindle length around 112 to 113 mm. So the grams are a bit of a toss up.
With bottom brackets, any reputable brand from the early 90's are all within a few grams of each other for a given spindle length. A few grams can be saved on the depth of the cups, not much on the bearings.
Titanium or aluminum chainring bolts... by density, aluminum is lighter. The lightest chainring bolts made were by a company called Crankomatics, but I have yet to come across a set (of course I haven't been looking too long).
Chainrings are all around the same weight-per-tooth-count-to-bcd-size. Titanium or aluminum... here the grams are around the same per size and tooth count as well. Old Action-Tec rings are very light weight...but so are mid 90's Middleburn rings.
