Always looking, this is new (to me) even though it is rated for higher power at higher RPM it still makes around 35hp@3600RPM and at 42kilos out of the box has some possibilities.
http://english.gkengine.com/a/product/shijie/engine/2016/0622/38.html
They also have a 1000cc that looks very similar.
http://english.gkengine.com/a/product/shijie/engine/2016/0622/38.html
They also have a 1000cc that looks very similar.