oil filler cap

[Mark Rivera <marr@xxxxxxxx>]

I keep getting vaporized oil build up on my cap over the filler hole. 
The o-ring seems to be in fine shape. I gather from the number of 
aftermarket replacements available that this is typical, and hence it is 
a commonly upgraded part.

Is there a replacement which seems to be the best, or some to avoid etc.?

Thanks,
Mark

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