Join Date: Apr 2002
Location: Dandridge (Near Knoxville), TN, USA
Also, a number of people have had the heads of the filter bolts snap off, even using a torque wrench!
I sold quite a large number of sets of better screws to prevent them breaking. The standard ISO grade 8.8 screws BMW uses are just about at their limit when tightened to the stated 10NM. The grade 12.9 ones I was selling are not even close at that torque. (The grade number is stamped into the head of the screw)
From a major metric fastener company's technical data:
Tightening torque, lubricated, for a M6 screw to reach 90% yield value of the screw:
Grade 8.8=9.9 NM
Grade 12.9=16.5 NM
You can see that BMW is recommending a torque for the standard grade 8.8 screw that will go over 90% of the yield rating for the screw! That leaves NO room for error. 10% overtightening can easily overcome the yield strength of the screw.
I don't want to achieve immortality through my work...I want to achieve it through not dying.
EX: '01 Black LT, BAT BYKE (Totaled at 110,000 miles)
IBA SS, BB, BBG, 10/10ths.
No bike now, but maybe in the future.