The Chiliad Challenge is a side mission in Grand Theft Auto: San Andreas. The mission is started by entering a parked Mountain Bike on top of Mount Chiliad between 7:00 and 18:00 and having a cycling skill above 40%. The goal of the mission is to be the first to reach the base of the mountain while racing with other mountain bikers down the mountain. There are three courses that need to be completed for 100% completion. All three courses share the same finish zone and the final sector.
Whereas in any other vehicle race wherein one can shoot at other contestants and get away with it, in this muscle-based race, if the player attempts to shoot opponents, not only will the player fail the mission, a one wanted star will also be obtained. Typically though, trying the race again at the top of the mountain will help lose the cops. The player can, however, get off and use the sniper rifle (no other weapon can be used) to eliminate them without penalty.
- Scotch Bonnet Yellow Route: (Reward: $500) This route lays mostly in the southwestern face of the mountain; it is the shortest way down to Angel Pine in distance and time but it is also the steepest, and corners are very closed (almost 180º most of them) and tricky due to the reduced grip of the dirt track and the descending factor. A careful braking and cornering is the key, and little sprinting is used. There are plenty of places where CJ can fall off the road and down the mountain from great heights, but some of them are protected with fences. Once this event is won you gain access to the next event.
- Birdseye Winder: (Reward: $1,000) This run uses the north face route to descend and then turns along the west side and then south down to Angel Pine, it is longer and less steep downhill overall than the previous route but also has some long and leveled straight sectors where CJ can sprint for a while and take the lead easily. However, side protections are even less than in the previous event and there are still some difficult corners. Once this event is won you gain access to the next event.
- Cobra Run: (Reward: $2,000) This race will start mid-way down on the south side and follow a narrow trail which is very tricky in the beginning, with an elevated part; after a jump the second half allows a higher speed as it's wider.
- While in The Chiliad Challenge, get off of your bike and jump off the mountain. Then open a parachute, the game will return you to your bike, but you will still have an open parachute on your back. The parachute then loses all of its function as a parachute. The video can be seen here on YouTube.
- There are a couple of ways to easily complete the Chiliad Challenge races, and the methods are recommended due to the lack of a retry option (after failing a race, players must drive all the way to the top of the mountain again):
- In the first two races, one can block the entrance into the downhill path with the nearby Camper or Journey. It will still be parked there after these races start and all (or most) of the competitors will bump into this barricade and fall off their bikes, allowing an early lead.
- A much greater tactic that works on all races involves the player killing stationary competitors with the Sniper Rifle before crossing the finishing line. Players should let all the racers pass the finish line, but not cross the finish line themselves. Dismount and quickly kill the 5 competitors while they stand or sit on their bikes in the ending zone; the sniper rifle is the only weapon that allows this – any other weapon used will disqualify CJ. Also be aware of the timer that expires while the player is off their bike. As each racer is killed, the player's position will move up. This works for all three races. A video showing this can be seen here on YouTube. Note that this strategy requires a little bit of luck, as sometimes some of the bikers do not end up going fully through the finish line and immediately ride off away from it, resulting in them disappearing.