I'm trying to discover what caused the power loss during my last
flight.
> There was some black "gum" on the prop. Has anyone seen this
before?  I'm
> beginning to suspect that I was running on one set of plugs,
but restricted
> fuel flow has also been suggested.
>
> Anyone who's inclined to apply their knowledge & experience to
this, please
> take a look at:
>
>     http://canardaviation.com/chap29.htm#diagnostics
John, I looked at your site briefly but didn't see any more on
the gum.  An exhaust leak on a 2 cycle engine burning 50 to 1
does produce a lot of black gummy tar like stuff yet the exhaust
passage can be clean as a whistle. Maybe this is similar.
Peter