Any problems with ignition issues during high humidity days, rain, fog, whatever, can often be traced to the black/gray OEM coil fitted to the R65. Tiny cracks in the plastic case are the death knell for the aptly named Crack-O-Matic BMW coil. On my '81, the cracks appeared in a circular pattern on one end. Had to actually clean the coil to find 'em. I've seen photos of a coil with a longitudinal crack running the length of the coil.
Herr Crack-O-Matic can trace his heritage back to the English
Lord Lucas, the Prince of Darkness, his third cousin twice removed.

This is my recommendation for some ignition coil peace of mind.
The Dyna Brown -
see? I swear it's orange- is an easy plug 'n play. Now that you have an Airhead, it's time to introduce yourself to Rick Jones at Motorrad Elektric. Â
http://www.motoelekt.com/index.html  Rick can assist with all manner of electrical issues. Plus, you can call him with tech questions and he's actually happy to talk with you. Northern Alabama he is.
Everything you need for installation is included with the Dyna package.
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+[/size][smiley=thumbup.gif] for Mike's XS. This Yamaha specialist in Florida has the NGK goodies and many other electrical wiring bits that cross-pollinate with our Airheads.
Monte