Follow the link. Image heavy for dial up users. You can click Slideshow then F11 on your keyboard for full screen.
http://picasaweb.google.com/toycollector10/SidsRun2009#The engine with the cobwebs in picture 8 is homebuilt. An atmospheric inlet valve and chain driven overhead cam exhaust. Yes, it's a SOHC1. There is also exhaust (oil in the mix) that blows down past the cylinder to lubricate the bottom end at the flywheel. The barrel is made up from two Honda C50 engines one on top of the other. It runs fine.
Are you North Americans familiar with the Ducati bikes shown and the Puch mopeds? It's a crazy day out. Note the Suzuki Maverick with the Sachs rotary lawnmower engine. There's a big Maverick following in New Zealand, much as there is a big FS1 club in the UK. And for the same reasons basically.
That's my CB175 in pictures 1 and 52. It red lines at 10,500 rpm. It's more fun than a barrel full of monkeys. Dare I say it, more fun that my '69 K0 or the Big Zed One.
Can someone please identify the bike in picture 211 for me. It's got a push rod 4 stroke with what appears to be a compression relief valve of some sort? Cheers, TC