ALL R1200's (and other BMWs) - NHTSA investigation into fuel leaks progressing..

AntonLargiader said:

On the Hexheads, the QD isn't subjected to the same sort of heat. I have been upgrading them on a by-eye basis so far, but I upgrade all of the 11xx ones every time now.

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swall said:

I am an R1200R rider and materials engineer with automotive experience in metals and plastics.I have been involved in NHTSA recalls. From what I see in tribble99's photo, the problem looks to be one of environmental stress cracking--a combination of stresses in the component and some environmental factor that leads to cracking over time. The corrective action for such a problem is to either reduce the stresses or eliminate the environmental factor. The stresses can be from the tightening of the male fitting and/or from residual stresses in the plastic molded part.The environmental factor could be fuel related or it could be from external factors, such as service environment (i.e. heat, air pollutants, cleaning agents, etc.) I am not familiar with the band type fix for this issue, but one problem I can see with this approach is that injection molded plastic parts have draft on the surfaces, like bosses, which results in a taper. Hard to clamp on a taper. You also have surface cleanliness, which works to defeat adhesive repair attempts. Plastic molded parts typically have release agents applied to allow extraction after molding and this inhibits adhesive bonding repairs unless the surface is scuffed up. One other comment I have is that with a metal male fitting vs a plastic one, there is the possibility of developing higher stresses while tighening the metal one in an uncontrolled installation process.

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JayElDee said:

The term you use, "by-eye basis," does that mean you do not remove the tank solely to look for trouble, but if you have the tank off for some other reason then you will inspect and possibly replace?

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