== Spelling of his last name == 

 I doubt that his name could also be spelt Reinhold Jöst (o-umlaut instead of oe). I'm quite sure the only correct spelling is Joest for the following reasons: 

 # Take a look at the CV/Bio published on http://www.joest-racing.de. It's available both in English and in German language. Although there are lots of umlauts in both versions of the text (indicating that no technical issue prevented the author from using them), the name is spelt Joest for exactly 15 times, whereas Jöst appears not even a single time. 
 # The name Joest (in this spelling) originates from Dutch and not from German, e.g. see the medieval painter Jan_Joest. Therefore, in this case, German umlauts aren't appropriate. Indeed, the name also appears in its Germanized version Jöst. But people are bearing it either/or. 
 # My personal knowledge — I'm a German and I'm also bearing the last name Joest. I'd never spell it Jöst. (btw, I'm not affiliated to Reinhold Joest).