I thought they were valuable because they only came on the first run sand casts. Apparently not, only the misconception that they did. Whether your bike has one or not doesn't mean much as far as restoration goes.
The restoration "purists" would certainly take exception to that last sentence.
They are "relatively" rare and nice originals usually command hefty dollars.
I would certainly devalue a bike that was suppose to have one and did not.
No where have we discussed what was suppose to have one and what was not. 1. Can you tell me what was suppose to have one? 2. My sand cast #1644 doesn't have one. 3. Purists don't like powder coating but can't give me a valid reason why. 4. What purists want for paint on a frame restoration is inferior in every aspect to powder.
1. ALL SANDCASTS came from the factory with wrinkle tanks. You cannot always be sure regarding the K0's. It's usually safe to say they came with one if they have all of the other specific Sandcast parts. There may be exceptions and all of the above effects the value of Sandcasts and K0's. They are only worth what someone is willing to pay and that is usually determined by their level of authenticity.
2. Your Sandcast #1644 does not have the original tank. It would be devalued accordingly and that would run up the caution flag about other non-original parts.
3. The reason why is, THEY ARE ONLY ORIGINAL ONCE. Depending on an individual's required level of restoration, depends on how much they are willing to deviate from the original parts, paint, and everything else. A powder coated frame would have points taken off in a restoration contest. Wikepedia says:
"Automobile restoration is the process of repairing the degraded aspect of an automobile to return it to an overall "authentic" condition. Restorations should be historically accurate as a representative example of the production model. For example, the guidelines of the Antique Automobile Club of America (AACA) are to "evaluate an antique vehicle, which has been restored to the same state as the dealer could have prepared the vehicle for delivery to the customer"."
"In contrast to preserving its historical artifacts through restoration or to conserve significant vehicles by keeping original surfaces and materials, some owners make changes or add modern upgrades during the restoration of their cars that may reduce or enhance the value of the vehicle. In the U.S. a non-original restored car may be termed a "restored"."
https://en.wikipedia.org/wiki/Automotive_restorationThe same is true for motorcycle restorations. Like I said, they are only ORIGINAL ONCE and are only worth what someone is willing to pay.
4. True, but they did not come ORIGINALLY with powder coated frames.