High Speed Track allows you to travel at a much greater speed than any other rails can. This also comes with a dangerous cost of exploding and most likely dying if you don't design your rails properly.
In order to use the speed advantage of High Speed rails, you will need to boost yourself to the high speed using Speed Booster Rails.
When traveling at high speeds, your rails can't have any corners or you will crash/explode. In order to avoid an accident on a turn, you will need to slow yourself down before you make one.
To slow down you can either use a booster rail that is switched off, or a transition rail. However, sometimes you will need to use a couple of turned off booster rails, depending on how much you used before and how much you traveled.
- Place unpowered High-Speed Booster Rails or High Speed Transition Rails before a corner, switch, or disembarking platform to slow your minecart. Will often require eight or more.
- Elevate your High Speed Rails to keeps mobs off the tracks. Stone Posts make awesome looking monorails.
- Encase your High Speed Rails in glass to form safe and scenic routes.
- Animals only spawn on grass, hostile mobs only spawn in the dark. This knowledge will help you design your lines.
- Avoid slopes that are more than one or two tiles long. Minecarts were never meant to travel at these speeds and they sometimes catch the tile edges on slopes, causing the minecart to come to a halt (explode). The longer the slope, the more often this tends to happen. The issue is more apparent heading down slope because there is intentionally no slow down code for going down hill like there is uphill. If possible, avoid slopes all together.