A few weeks ago I bought a vertical shaft Honda GCV160 powered pressure washer for $25. The guy had left the washing fluid on it over the winter and it froze, ruining the pump.
Apparently, that happens a lot around here as there's always a few on Craigslist. A replacement pump, or a repair job costs almost as much as buying a whole new washer, so people sit on the ruined one for a while, then realize it's just taking up room and they sell them.
My intention is to mount with the shaft horizontal. That puts the carb in the rear and exhaust in the front. The nice round mounting flange looks BTR-ish and it's bolted to a fairly thick plate on the washer cart. I plan to make a template the size of that plate, mark the chassis tubes on it and cut the mounting plate to bolt 'er in. I'll do this first to get a motorized bike rolling while I work out the details on the lil' twin.
As to how the single lobe works 2 valves....it's similar to my old 4-stroke pushrod Ryobi 26cc wacker engine. There are 2 rocker arm/cam followers that contact the lobe about 45-60 degrees apart. Depending on their pivot point and clocking locations, they either push down on a valve tip, or up on a pushrod. On the Ryobi, the arms are shaped like this Γ˚ and on the Honda, like this ˚Γ. On the top horizontal leg, the dot represents the pivot point and the other end does the work. The bottom of each vertical leg has a follower that rides on the cam lobe. There's a mirror image of these for the other valve in each engine.
I wish I could explain it better in text, but there's nothing in the Windows character map that looks any closer. Imagine a traditional cam lobe shape rotating inside a pair of mirror image upside down capitol Ls and I think you'll get it.
Honda GC160 Parts List and Diagram - (Type QHAJ)(VIN# GCAH-1000001-9999999) : eReplacementParts.com
Look at page B and study the parts diagram for the valvetrain.
MHF
P.S. is this the compressor engine you're talking about ?
Double the R.A.G.E. - scale V-Twin model Engine (Homemade) - YouTube