Post-Sale Update: I had to bring this post to the top just to remind you all about this bike and share the final sale price. After 102 bids on eBay, this Honda CB750 Sandcast Prototype sold for $148,100. Wow.

I normally don’t post on Saturday, but today I had to feature what might be a once-in-a-lifetime opportunity – one of the four original prototypes of the Honda CB750. Many people know that the first 7,000 produced had sandcast engines, and their relative rarity has increased their value over the years. What many don’t know is that Honda built some pre-pro prototypes to show off to the American public. 4 were built, and only this Candy Blue/Green example is still around and kicking.

To the untrained eye, this bike may look like any other CB750. But the seller includes a detailed list of the many individual differences, including the one off engine covers, chrome fenders which show scribe marks from the engineering about where holes should be drilled, no kill switch, no tool tray, and hundreds of other little details. For more of the story on this bike, check out this article by Mitch Boehm on Motorcyclist.

From the ad:

What ever happened to those rare first four hand built bikes?

– The Red bike was taken to the crushers in Iowa back in the early 1990s (I know, as we got there literally days too late, coming away with only a small handful of parts from it).

– The Gold bike made its way to Europe, only to be completely disassembled by its owner (who has no intention of selling) and it has remained in that state for the last 25 years or so.

– The Dark Green bike has never been heard from, thus leaving this (Blue/Green) bike left of the four.

– The Blue/Green prototype motorcycle featured in this auction just happens to also be the (only) one American Honda used for all of its initial promotional brochures, flyers, and sales literature. Example photos of these early promotional items can be seen here, and most easily identified by the bike’s very unusual front brake caliper.

Frankly, I’m not sure what else to say. This specific Honda CB750 Sandcast Prototype is going to sell for a tremendous amount of money to someone who cherishes old Honda’s. It’s probably the most valuable CB750 that still exists. Compare that to a previous bike from this seller (one of the first 20 off the production line) which sold for $75,000.

Find this historical Honda CB750 Sandcast Prototype for sale in San Francisco, California with bidding up to $92,100 and the reserve not yet met (!) here on eBay.

This bike-uriousity was found by Chip L. of The New Voice of Old Cars.