> I just did a compression test on my 84 Westy which has 153K on the clock (I
> presume that this is the original engine but cannot be sure).  I got
> the following readings (these are "wet" i.e. with oil in cylinder):
> 
> These look pretty good although I am puzzled by #4 which is 23psi above the
> spec for a new engine (90psi).  How could this happen?

   Carbon build up on the piston or other parts of the combustion
   chamber. Try the old water trick.
                            Eric