OK- I’m stupid. I’m reading through Frank’s very detailed instructions on how to install my new PC’s. The manual says to tighten the crank bolts very tight. Hello! Say no more- I’m a guy, I can do that! OK, settle down, let’s be smart about this and get the ol’ Zinn book out and figure out how tight is tight. Good ol’ Zinn says to tighten the crank bolts to 305-425 lb-ft. Pound-feet!? Can this be right? That’s a SH-T load of torrque. My torque wrench only goes to 150 lb-ft. Yes, there it is in black and white. Pound-feet. Zinn is the master, so off I go to put the big hurt on my crank bolts with my torque wrench. Long story short, I get to about 60-70 pd-ft, and the drive-side bolt starts making a sickening little grinding noise. Hmmm. Could this have been a typo after all? Went to http://www.ex.ac.uk/cimt/dictunit/cctorq.htm and did a quick conversion. 305-425 pound inches would equal 25.4 - 35.4 pound-feet. This sounds more plausible. Went to the Shimano sight and my worst fears were confirmed. Zinn made a typo! Arrrrrhhhh! Of course, any female coming across this error would have double-checked it before happily running off to see if they could, in fact, apply over 300 pounds of torque to their crank bolts. I’ll be going by the LBS for a new Ultegra BB today
I’m sure this is just as easily found on the website- but is there a BB recommendation for PowerCranks? More specifically, is there a list of what works?
And don’t feel bad about over-torquing, before I got a dork wrench I just cranked until things made that sound. It was when I knew I was done.
I’m having a lot of fun rebuilding my entire road frame now.
I don’t think this is a case of testosterone poisoning. What I have found mostly is that this syndrome is more likely presented as a loss of desire to read and, to a lesser extent, a failure to comprehend.
The typical 8mm Allen wrench has an arm of such a length is it is almost impossible to over torque. A torque wrench designed to go over 300 ft pounds, however is industrial sized. Where the heck did you find one? do you work in a shipyard?
Frank
ultegra, 1054 wont work because the splines are not chamferred and DA by all accounts leaks ???
Anyway I went and bought the Ult and it went together beautifully.
The typical 8mm Allen wrench has an arm of such a length is it is almost impossible to over torque. A torque wrench designed to go over 300 ft pounds, however is industrial sized. Where the heck did you find one? do you work in a shipyard?
Frank
No- the torque wrench only goes to 150, so I figured I was well within the safe margin even if I “pegged” the wrench. So off I went. I just looked down and saw that the needle wasn’t at the end of the scale yet, so I kept pulling. This 8mm allen wrench contraption that you speak of- this is no good. I can’t possibly strip a bolt with this- my hand would hurt too much!