so i bought a crankset off ebay (a shimano 105, with bb5500), but it just so happens that it didn't come with the crank bolts that the original set did. i did a search for what bolts i'm supposed to use (m12, m15, etc.) but came up dry.

would these https://www.probikekit.com/display.php?code=X0010 work fine?

You need the specific bolts for a Shimano Octalink bottom bracket and they are not hardware store items. You will also need the special washers that are part of the installation.

The link you show has the correct bolts on the left side of the illustration. The bolts on the right side are for a square taper crank. Be sure to get the washers too.

That link at PBK says "pair for standard chainset." Given the price and description, that makes me believe that they are for a square taper crank (the bolts shown on the right) rather than Octalink.

Here's a link to Octalink bolts:
https://www.universalcycles.com/shopp...&category=1618

appreciate it guys! didn't realize they'd be that expensive (i was trying to go super cheap on the build)

that said, would octalink V2 bolts (i.e. 6600, 7800) bolts work on mine?

6600 and 7800 are Hollowtech II cranksets which use a completely different BB system. Octalink V2 differs from Octalink V1 only in the length of the splines on the BB (based on what I've read, no personal experience with these cranks). I see no reason why Shimano would have changed the bolts between V1 and V2.

sorry for all the stupid questions, but am i wrong to assume any m15 bolt will fit octalink splined BBs? https://www.jensonusa.com/store/produ...ank+Bolts.aspx

The Truvative bolts look right but I'd call Jenson and ask.

as expected, jenson couldn't give a firm answer as to whether or not it'd work... and shimano of course tells me i have to use shimano bolts. go figure.

Easy solution; use the Shimano bolts.