Khara Descent TT is the most difficult one to get gold on in Pure. The times set for gold are somehow made very low on this track. I think Flash speed was the most difficult one, if I remember well.

For speedlap: Hit the boost from previous lap just before the startingline. Going with highspeed through the chicanes, then hit your turbo just when you come out of the right turn before the splitsection. Don't hit speedpads while using the turbo, it slows you down instead of giving you more speed. This turbo will give you enough speed to do three BRs on the descent down, take the left side. Furthermore it is a matter of hitting all the other speedpads and taking the cleanest lines. Oh yeah, almost forgot, when you are able to sideshift on a speedpad it will give you just a little extra speed.