I restored a 1969 Honda CB750 Sandcast in my tiny garage and captured it with my iPhone. You can see more of my work at my website: www.ujenimotors.com
Answers to a few common questions:
1. Indeed, I did use the original pistons. They were undamaged and showed no signs of abuse. They were easily within spec too. I cleaned them gently, installed fresh rings, honed the cylinders and ended up with a fantastic engine. Granted, they aren't shiny, but I try not to replace original Honda components when I don't have to.
2. The red paint inside the engine cases is Glyptol. Its an engine epoxy that is used to seal the engine (sandcasts have been known to leak through the porous walls). Glyptol also speeds up the flow of oil which makes the engine run cooler. Got the tip from Vic World many years ago. I've done this on many engines and never had an issue.
3. The cost to restore a bike like this really depends on how much you can do yourself. I was going for a show-level restoration and I am able to do almost all of the work myself (not metal plating or machine work). Depending on the condition of the bike being restored, I would say a restoration like this costs between $10k to $25k. Not including labor :)
4. This is indeed the bike that won Best of Show at the 2019 Quail Motorcycle Gathering. I'm still in shock!
5. Though I will sell the bike someday, it is not currently for sale.