I just got a Honda CD200 Benly 1981. It starts on the button every time. I've been looking for one for around 6 months and this came up. It's a bit scabby so I ripped it all down for a complete restoration. It's now in a million bits in two sheds. I'm a retired Wall of Death performer and we used these Honda's on the wall. They never let us down once in the 40 years I performed. I'm also filming the rip down and build up.
Using a digital caliper to measure the stem is not the right way (you probably already know) for accuracy you will need to use a micrometer. The o-rings are called valve stem seals and there are two springs because a single spring could collapse or become weak due to resonance on certain rpm's which would make the valve drop down or float, then the second spring works like a back up. DONT use a collet or a hard fix on a valve when grinding, use a peace of fuel line instead or a rubber hose that fits to rotate the valve to prevent sideways forces on the valve stem. These are just a few thing I learned over time I hope it helps ;-) Good luck on the project, that engine will run as new when it's done I'm sure.
@@TooManyProjects I would also leave it as is and it will probably be fine, otherwise you would have to redo the whole head including valve seats and valve guides which can also be done in the future if necessary.
Good content. I also own a CD200 made in 1987. And I have an idea to install a oil cooler to it. Consider doing a video on it because these bikes get heated in long journeys because they have air cooled engines
