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No matter how long the enforced isolation due to the virus, I don't think I'll run out of interesting videos to watch on Youtube.
Kawboy will appreciate this one, I'm sure.
Astounding as the machines are, I am in awe of the towering intellect behind the design and programming of them.

Thanks Jim. It's a fascinating time to be in automated manufacturing. CAD/CAM is the future. Who would have thought you could chuck up a piece of Chrome Moly and completely machine a crank from it in one go. Machining now is in the hands of a computer programmer and a flunky to chuck up material and remove finished product and I suppose even the manual work could be automated.

I guess most crankshafts are forged, so they don’t undergo much machining. I recall, in the 1960’s, Ford Britain used a cast crankshaft on one of their four cylinder models. It was known to be an Achilles heel by engine tuners.
The built-up roller bearing cranks such as fitted to the KZ900 / 1000 and GS750 /1000 interest me. They must have been so expensive to produce, requiring meticulous alignment of each part. I wonder why they used that design on a four stroke engine?

They used that type of manufacturing because its the most cost effetive and quickest way to mass produce.
They are mainly good for high mileage, but Kawasaki did have some batches which "slipped" out of place making one piston reach TDC slightly out of timing but did not damage anything else in the process as the stroke was not affected.
I had a 1980 GPZ1100B1 with that fault at only 5,700 miles, which still ran on 3 cylinders perfectly well.......but obvioulsy not acceptable !
The crank had to removed and realigned (pressed) and refitted, then all as good as new.

Pete F
UK

Thanks Pete.
By the way, I’m looking forward to seeing what you’ve done to your latest 1300.

Back in the day a good friend had a Kawi. 1100 that "spun the crank" Had to be torn down and I remember him saying they welded the crank.