"Old dryer ring" - "vecās kaltuves aplis" sounds good! And te picture on a ticket is appropriate!
My bike is now ready - some recent pictures:
Here's some pics of my homebuilt Riga/ D8 racing bike.
In Estonia there's a whole racing leaque of similar bikes, the engine block and cylinder has to be from "D" type, but can be freely altered. Typical bike has reed valve intake, highly tuned water cooled cylinder, PVL ignition and lot's of custom made racing parts inside.
More info and pics - http://oldmoped.proboards42.com