This is my DS50, better known as Alabama here.
The idea was a sleeper. It has a Maxi 70cc cylinder machined to fit underneath the fan cover, and a stock maxi exhaust with only the header replaced with a 28mm one. Bing 17mm with intake from a Magnum X. You need to look closely to see that it is not stock, but it does 75 km/h. Would be fun to see how it would do with a better exhaust :)