I’m looking to build a wooden engine overhauling stand as displayed in the attached photo (#5). Does anyone know the optimal dimensions ?

Might depend a little on whether the engine is a big block Chevrolet or a Stihl chainsaw...

But seriously... DEET might know... there's probably two or three sizes for the Yamaha Enduros... small bike under 90cc... 90cc to 175cc... and 250/360/400.

What I've used years ago was an old small crate from something that was big enough for the side covers to fit in but just small enough that the engine mounts would rest on the edges of the crate when the engine was on its side. I removed the head and cylinder before flipping engine on its side on the crate. So not too hard to figure out. Hope that makes sense.

Thanks Mark, currently I’m working on my HT1 90. I assumed there would be a few different sizes based on engine displacement. I’ve taken a few measurements with the side cases off and will probably cut up some 2” x 6” and put something together. I seemed to remember an old thread about building one but couldn’t find it.

Years ago I built one for my 360, 12"x15" (Four standard 2x4's all 12" long). Recently I used it for my 175 rebuild and it was slightly too big, It worked, but lopping an inch off all dimensions would have worked better.

High Joe,how are you?
What i did was get four blocks of wood 4 x 2 English inches and supported the clutch side crank case with the clutch in place to get my clearance from the surface of my bench. Spaced it so it supported evenly on the 2" side. Then i got some edging strip and nailed it on to stop the casing sliding around. Then screwed it all to my bench. After id finished i simply unscrewed the whole lot and put them in a placi bag in my filing cabinate so it doesn't take up space.
But to answer your question no sorry

Using 2x4 lumber, outside dimensions are 14"x10"

Thanks Deet...