Just back from a cruise to Alaska...the weather was better in the rain forest up there than it is now in Spokane. Good day to change the oil.
Today, out of curiosity I decided to see what happens when I tried various used and new crush washers on my FJR. I do not offer the results as absolute truth, with any conclusions or indeed , for anything except for idle interest.
Method. I took each washer under test (WUT) , installed it on the drain bolt, and hand tightened it using a deep well socket with no ratchet or breaker bar. I then marked the bolt’s relative rotational position by marking its outer edge with a magic marker and putting another mark on the protective flange. I used two different torque wrenches which I tested using a scale and grade school math. One was set to 20 ft-lbs (20) and one to 35 ft lbs (35) . I then tightened the bolt as smoothly and continuously as possible and using a mirror (which changes the direction of rotation) , took a pic of the rotational movement and noted it by measuring the pics on my computer screen with a protractor. I tested two washers, the OEM one, new and used, and the Honda 14000, new and used, which is used on my CRV and my NT700V. My NT700v says to torque the bolt to 22 ft-lbs. My CR-V manual says 33 ft-lbs. IIRC, the FJR manual says 35 Ft-lbs for the oil drain bolt, 17 for the diff drain and fill.
Last Fall, I put in the winter oil and put on a new OEM washer, torque to 22 ft-lbs. I didn’t ride very much this winter. I broke the torque loose with a satisfying “snap” letting me know the bolt was in no danger of falling out.
Test one. WUT is OEM washer, used once. I torque it to 20, and the bolt turned 25-30 degrees. I broke the torque (easy) and then tightened to 35. The bolt had turned 60 degrees from hand tight.
Test two. WUT is a new Honda flat washer. 20 produced about 60 degrees of rotation. 35 produced about 100 degrees. (No, I did not change washers between 20 and 35 but I didn’t break the torque either.)
Test three. WUT is the used Honda washer, now significantly flattened and distorted. 20 produced 30 degrees, 35 produced about 70.
Test four. WUT is a new OEM washer. I torqued it to 20 ft-lbs and the bolt head rotated 270 degrees. I elected to not torque it to 35 ft lbs and filled the crank case.
Two pics...one of the OEM new washer test, two is what the washers look like after 35 ft-lbs of torque.