Mass Start Events

Scratch race:

First across the line after XX laps is the winner, just like a road race.

Point a lap:

First rider across the line each lap earns a point. Highest points total wins. Generally 3,2,1 awarded to the first three finishers on the last lap.

Win and out:

Normal race until the bell lap. The bell sounds - sprint. Winner of this sprint is first place and can retire from the race - everyone else keeps going and the bell sounds again - sprint. Winner of the second sprint is second in the race and can retire - everyone else keeps going and sprints for the 3rd and final time where places 3rd, 4th 5th etc. are determined. End of race.

Points race:

Every X (generally 5) laps, points will be awarded to the first 4 riders across the line (5,3,2,1). A bell sounds one lap before the points are awarded. Highest points total wins. Generally, double points are awarded on the last lap and sometimes also at half distance.

The rules for lapping the field have changed at the UCI level. I am unsure as to whether they have filtered down to the Hellyer level yet (Hellyer officials generally use the USCF rule book). In the past, if you lapped the field, you were then only racing people on the same lap as yourself, even though everyone could sprint and win points. In this case, number of laps took precedence over points total and the points totals only separated riders on the same lap. IIRC, now the benefit of lapping the field is that the riders who gain a lap are awarded 10 bonus points and are still competing against all the other riders, even those who have not gained a lap.

De'il, Devil take the hindmost or Miss and out

The last wheel of the bunch across the line each lap eliminates that rider. When 3 riders remain, there is a free lap and then the bell is sounded for the final sprint to determine the podium places.

Other events

2 to 4 riders, 3 laps and the first over the line is the winner. Sounds like a scratch race - it is, but tactics are an incredibly important part of sprints. The race is generally a cat and mouse game for the first two laps, with each rider trying to fool the other into jumping early and therby leading out the sprint. For this reason, only the last 200 metres of a sprint race are timed.

Riders draw lots for position on the track and start side-by-side held upright by holders. The rider at the bottom of the track is required to lead out the race for generally at least the first half a lap at a walking pace. After that, trackstands are not uncommon (this is where the term comes from) as the rider in front tries to force the rider behind in front.

Track sprinters generally have huge thighs, as the sprint is usually won with a quick jump.

Chariot Races:

6 riders starting side-by-side, 500 metres, first across the line wins. This is an all-out sprint from the gun, with the rider at the top of the track benefitting from the banking, but having further to travel. 6 strapping lads all wanting to be in the same space results in contact!

Kilo and 500 metre time trials:

Exactly what it means. One rider at a time, starting with a holder and TT-ing for the distance. The start is all important in such a short event. Kilo riders also have huge thighs.

Pursuit:

2 riders start on opposite sides of the track and try to catch each other. The rider who catches the other wins, or the rider with the quickest time over the distance, generally 3 or 4 kilometres. Also done in teams of 4, with the third rider stopping the clock.

Italian Pursuit (Olympic Sprint)

2 teams of equal numbers start on opposite sides of the track and try to catch each other. The lead riders peal off after each lap. Generally, the weak riders lead out, leaving the strongest rider on each team to contest the final lap.

A special case of the Italial Pursuit is the Olympic Sprint, which uses teams of 3, and is therfore run over 3 laps.