square taper crank bolt spec?
05-19-22, 06:34 PM
#1
Senior Member
Thread Starter
Join Date: Mar 2008
Posts: 1,514
Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 231 Post(s)
Likes: 0
Liked 10 Times
in
9 Posts
square taper crank bolt spec?
I swear i am getting stupider as i age. I cant find any threads that reference a proper torque spec for a square taper bb. I could swear it was something like 35 ft lbs but wanted to be sure. Does any one know? Sugino AT cranks on a Tange Sekai seal bb if that matters.
05-19-22, 07:05 PM
#2
Senior Member
Join Date: Feb 2012
Location: Rochester, NY
Posts: 18,071
Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4199 Post(s)
Liked 3,851 Times
in
2,301 Posts
I have used 30-35 ft lbs for tapered square arm retaining bolts for decades. IIRC older Euro ones often wanted a few lbs less as their alloys tended to be softer. When Hollowtech came out and their bolts called for 40ish I was surprised. Andy
__________________
AndrewRStewart
AndrewRStewart
Likes For Andrew R Stewart:
05-19-22, 11:10 PM
#3
Junior Member
Park Tool's web-site info. for square taper cranks suggests a range of 34 Nm to 50 Nm ( 25 ft. lb to 37 ft. lb. ). That's with the bolt heads' undersides and threads lubricated with grease or anti-seize.
https://www.parktool.com/blog/repair...on-three-piece
https://www.parktool.com/blog/repair...on-three-piece
05-20-22, 10:52 PM
#5
Senior Member
Join Date: May 2004
Location: Southern California
Posts: 2,191
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 114 Post(s)
Liked 119 Times
in
92 Posts
Park also lists torque specs for various fasteners and manufacturers: https://www.parktool.com/blog/repair...s-and-concepts
