Is this the first official single-speed MTB ?

Back in the mid '80's I got the notion to build a single speed mountain bike. People were riding single speeds in the dirt and a few races even had a single speed class but nobody was building a bike specifically for such racing, at least until this one was built in about May of 1987. It might have been the first time I used a wishbone style seatstay, a primitive handbuilt one. The bike also had a 24" rear wheel and a 26" front , a combo that I thought would make the bike accelerate easier while kepping the front end stable and familiar. At the time single speeding in the dirt was a hard sell but once I tired it I was pretty much hooked. It was fun to sprint away from folks on thier fully laden geared bikes weighing much more .The lack of chain slap made the bike almost silent on the trail, a real treat. I guess it caught on eventually...