Building a twin cylinder inline i.c. engine.

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Is the crankshaft counter-rotating in "RUNNING IN TAPPETS IN GUIDES 001" because of setup available?

When valves cross, exhaust should move first to release gases , than admission moves to take fresh mixture.
Admissions of both cylinders should be clearly opposed (as timing) - I believe? Hard to follow on the video...


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Crankshaft does not counter rotate as there is an idler in the gear train. Both rotate the same way.

Brian has also mentioned that he set the cams so that the exhaust leads, whether he got it right is another matter.
What I meant was maybe cold-run setup (electric motor) could rotate engine differently than normal spinning direction. Direction is (maybe) meaningless for cold engine break - or somebody could decide so, for certain reasons.
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Looking at the video it looks like the rear cylinder(with weight) the valve timing is reversed, the inlet opens then the exhaust opens, then it rolls around through comp, power stroke. May be the problem.
That's an old video, Brian has reset the cams in the way the original designer describes since then.
I know this is an old video and Bryan has adjusted the valve timing but I believe at that time he had one side firing. He also changed out plugs, ignition to confirm OK.

Just me but I don't like anything ''Tight'' on a small engine, especially around the valves, as they need to move quickly and easily. Any delay in the movement through the tight fit can easily leave valves open or closed at the wrong time just by a few milliseconds delay.

I also think the twin carbs need a degree of balancing before hand to ensure it will run with that setup or revert back to single carb.
I have worked on the inline twin all morning. I have electrical gremlins today. I have to go out this afternoon and will take my 12 volt battery to the nearby battery place and have them test it for me. I have, in my possession, two 12 volt automotive coils and one snowmobile dual output coil, and none of them are working the way they are supposed to today. Mechanically, I think everything is fine, but I'm getting weird results from my ignition.
Battery place said there was something weird going on with my battery. They will put it on their charger overnight and if it doesn't take a charge I will buy a new battery. I was getting a very weak white spark from my coil---sometimes.