Originally Posted by
steelbikeguy
I've always just tightened once... until..
There was the time when I bought a Phil titanium BB to use on a Campy Record crankset. i.e. the classic late 70's/early 80's Nuovo or Super Record crankset. I thought I'd replace the Campy BB with a lighter Phil BB. I contacted Phil to be sure that the axle taper was suited for the Campy, and they assured me it was. I installed it as typical, and did a few rides. Unfortunately, I was in the middle of a ride when I discovered that one (or both?) arms were a bit loose! I was close to one of the LBSs, and they snugged the bolts up. No issues after that.
The mention of titanium bike parts brought to mind a tip concerning titanium bolts (and aluminum bolts, such as Cinelli 1R stem bolts). To install a lighter (and weaker) bolt while avoiding failure of the bolt during assembly or out on the road, use a steel bolt to tighten the fitting to the torque spec and then remove the steel bolt and install the lower-strength bolt.
In other words, the torque required to keep the assembly correctly tight (once the proper installation torque has been reached with the steel bolt) is lower than that specified for initial assembly.