I bought these 2, 4 years ago, intending to make 1 from the 2. Covid intervened, and with time on my hands, I made 2 from 2.
Sold the gold one, but later discovered the green one had 2 spun bigends, only showed up after riding a couple of minutes when the engine would start knocking and smoking. It was sweet as when cold. PO, who is an expert on these agreed to rebuild the motor for me for the cost of parts and machining, which was generous in the extreme. But it took 2 years, finally going well. One frustrating issue was the engine started easily and ran sweet, but fell flat at 4k rpm. Long story short, carbs were from a 550K and had 98 main jets and 38 slow instead of 100s and 40s. Took a while to find but all good now.