The only skill required to ride this track - in summer - is the ability to stay relatively upright on a bicycle.
In winter, it is a different story.
The track is clay, hard clay, and is covered in a green substance. I'm not sure if it is a slime, as such. I got quite a close look at it recently, after falling off my bike.
If you ride any bike, if your back tyre slides around a wee bit, you can control it.
On this track, in winter, your front wheel will slide out from underneath you.
Generally, you can't control it.
I'm of the humble opinion someone will break their neck or kill themselves on a Mt Parihaka track. I have fallen off my bike three times now, over the past five years, because Mt Parihaka mountain tracks become dangerous to ride in winter.
Especially after rain. Especially because of this slime.
They are not "all weather" tracks.
In Whangarei, a BMX track has been fenced off after a sudden, tragic death.
I'd like to challenge a safety-minded person to inspect the mountain bike tracks, to close the dangerous ones, or help the well-meaning volunteers who build them to lay some form of gravel or cover that makes them safe.