Motorcycle Repair: CM 250 Cylinder Head Torque Values, cylinder head bolts, torque values
QuestionI have removed the cylinder head from my nieces 1982 CM 250 to repair vandalism to her spark plug hole. What are the torque values for the cylinder head bolts (studs) and nuts.
AnswerI don't have a manual for that bike but the standard torques for the thread size would be close enough. I'd use the 8.8 grade torques below (foot lbs.
Regards
Rich
Bolt size Low Grade Grade 8.8 Grade 10.9 Grade 12.9
6mm 3-5 7 10 12
8mm 8-12 17 24 29
10mm 15-22 33 47 57
12mm 39 59 83 100
14mm 60 101 131 158
16mm 60-94 146 202 247
18mm 60-130 201 283 340
20mm 166-188 285 401 482