First off: thanks to all who wrote with suggestions.
Well, I decided to try the rosin suggestion. Degreased post and tube, scored the bottom3" of the post moderately with 120 grit paper, rubbed rosin on the post, tightened bolt fully, marked height with tape then rode it for 20 miles. Result: not 1mm of movement!
I am still a bit leary of a "dry", dissimilar metal interface under pressure scenario.......so I decided on another experiment.
Scored the end 3" of the post more heavily, radially. Liberal grease, fully tightened. So far it hasn't slipped at all, but then all I did was ride it home, 2 miles. It is like riding in an oven out there today!!!
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Neill Currie, Portland, Me 04102, USA.
The Mountain Goat website is at:
http://www.geocities.com/
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