"Don’t be tempted to buy a Octalink chainset" says
@Cycleops
Reasons for the latter are?
To reiterate Phil: because the OP has a square taper bottom bracket and one would have trouble fitting an Octalink chainset (obv).
Octalink is a splined fitting so not compatible with what you have.
Also who (apart from you,
@silva chooses to install Octalink, even Octalink 2)?
"In use, Octalink has been shown to loosen because it is not a taper-fit but merely a tight spline fit. Reverse torque loads can cause the crank bolt to undo, and the crank can be irreparably damaged if this is not checked. "
The Octalink system uses a spindle with eight splines. The splines provide a contact area between crank and spindle for an interface. Octalink exists in the marketplace in two variants, Octalink v1, and Octalink v2.
And from
@Yellow Saddle :
"Octalink was a spectacular failure and even a redesign of the first version didn't solve the problem. Octalink (1) had splines which were too short and Octalink (2) attempted to fix the failures with longer splines but Shimano's engineers under estimated the amount of lash in the splines which were enough to loosen the bolt and allow the splines to slip.
This problem was exacerbated by how easy it was to botch the installation. The entry into the splines was blind (you couldn't see the right way to put it in and had to guess) as well as press-fit. This means a poor start of the fitment could not be detected early on and one would just start cranking up the bolt, eating away the soft aluminium crank."
