Sky Dragster now has a new opening date, it's the beginning of the new season in 2017. Test runs are announced for the next weeks though.
There are also some new renderings showing the bikes, the cockpit and the station. Most interesting the information about the top speed: Sky Dragster may reach 60 km/h (37 mp/h)!
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Maurer AG doesn't exit completely, instead all their coaster stuff will be managed by Maurer Rides in the future while they still produce track and cars. There are four new coasters in the making. Source
It has already been revealed that the new attraction will be one of the most expensive at Europa-Park: 25 million euros. That's about the price of the "Arthur" ride.
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Well, that came unexpected! Skyline Park just announced "Sky Dragster", the world's strongest motorbike coaster with the possibility to determine the speed yourself!
It's going to be built by MAURER. Opening in July 2016.
Source: Parkerlebnis
^As from the story you ride on the back of the Cobra through the desert, the colour sheme makes sense to me. I assume that they wanted to match the colour with future theming so you can barely see anything of the track at all.
There's also a POV onride online now:
I have been to Holiday Park at season opening and both trains were in use. It was not crowded at all on this day. I think they use both trains always now.