Dave I sure got a rise out of you on the metric/ imperial measurements lol. I personally hate the metric system.
Dave are sure the straight edge is 100% straight? Are you able to get 2 spacers that are .75mm, what about getting a machinist to make 2 for you?
On second thought, it probably was unnecessary to use that straight edge, even if it's 100% straight. At a weird angle it could look aligned and at a different angle it might look way off. Not to mention a phone's camera lens has distortion. But just looking down the sprocket like a rifle sight it seems very in line. I guess the real test would be to take a longer straight edge and put it up against both sprockets, or a string like you're aligning tires.
I know zero machinists and finding spacers is actually a pain now that I've just looked. It all depends how perfectly aligned it has to be. I was planning on going to the hardware store, getting a big stainless washer and drilling out the inside if it doesn't fit on my axle. It'll probably be something like 1.5 - 2mm in thickness which should be fine.
Dave I didn't wish to hijack your build and start an argument against the metric system, America's stand against metricifaction is a topic for another
forum.
Haha, no problem. Hijack away! If anyone wants to talk about any random thing on my thread it's fine by me. I wouldn't call it an argument, though. Just a friendly discussion. But I like the metric system.

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1978 Honda CB550K