OK guys, be gentle. I hate to ask a dumb question, but here goes. Let me first say that I have worked on 2 and 4 cycle motorcycle engines for 30 years, but have only recently started fooling around with glow engines. Other than blow by passed the piston, what lubricates the bottom end of a 4 cycle glow engine? Is that it? If so, how can these little engines hold up like most of them do? What lubricates the valve train? Is there anything that can be done from a preventative maintenance standpoint that will be beneficial to the bottom end and valve train? Thanks for your help.