It seems that most can’t.
Some Lyco variants (which don’t have a combined dipstick + filler hole) can reportedly be inspected in so far as one can see some cam lobe(s), just about.
But it seems a dumb design. It would be so easy to have a screw-in inspection plug somewhere, or several of them.
Pulling cylinders to check the camshaft is ridiculous.
As the title says: Have you ever seen anything more impressive than that in mountain flying?
Watch the following video and see when you recognise the “strip”. (It’s actually an official USFS landing strip in Idaho — apparently still maintained, but reserved for emergencies only).
Too bad they didn’t post a video of the takeoff! (The other three vids on his Vimeo account are also not bad.)
P.s.: The guy in the video also offers flight training, see http://www.techflying.com.
Automatically generate highly optimised IFR routes in the Eurocontrol system.