Dear Abby, 

I've never written to you before, but I really need your advice on what
could be a crucial decision. 

I've suspected for some time now that my wife has been cheating on me. 

The usual signs... phone rings but if I answer, the caller hangs up. My wife
has been going out with the girls a lot recently although when I ask their
names she always says, "Just some friends from work, you don't know them." 

I always stay awake to look out for her taxi coming home, but she always
walks down the drive. Although I can hear a car driving off, as if she has
gotten out of the car round the corner. Why? Maybe she wasn't in a taxi? 

I once picked her mobile phone up just to see what time it was and she went
berserk and screamed that I should never touch her phone again and why was I
checking up on her. 

Anyway, I have never approached the subject with my wife. I think deep down 
I just didn't want to know the truth, but last night she went out again and
I decided to really check on her. I decided I was going to park my 2006
Yamaha R1 motorcycle next to the garage and then hide behind it so I could
get a good view of the whole street when she came home. 

It was at that moment, crouching behind my Yamaha R1, that I noticed that
the valve covers on my engine seemed to be leaking a little oil. 

Is this something I can fix myself or should I take it back to the dealer?