Road vs Criterium
Criteriums are actually Road Races. The main differences between a traditional 'Massed Start' Road Race and a Criterium are that traditional 'Massed Start' Road Races are based on a distance to be covered, while a Criterium is based on a length of time for the race plus a number of laps of the circuit to be completed.
Criteriums tend to be run on circuits and arguably provide a better spectator experience. A Criterium circuit is limited to between 800m and 3km any number of laps can be covered within the time period plus a few additional laps that are assigned to that grade. Any circuit larger than 3km is a 'Kermese' which is another variant of a Road Race which is usually based on a certain number of laps to be covered. Please Note: A Kermese does not have a 'Lap Out rule' as it is classified as a Road Race but requires the removal of spares, pumps and other accessories, as does a Criterium.
A Road Race, as mentioned earlier, is based on a distance to be covered and can be run as a mass start, criterium, kermese, a handicap, or a Time Trial.
One of the main rule differences with a Criterium is the 'Lap Out rule'.
In a Criterium if a rider falls or has a 'recognised mishap' the rider may report to the commissaire and claim a lap out. The rider gets a free lap and then rejoins the grade they were in at the rear of the group they were in when they had the fall and/or 'recognised mishap' (if a rider does not inform the commissaires or the mishap is not a 'recognised mishap' then the rider must chase back on).
In a other Road Races there is no such option. If a rider flats or has any kind of mishap they must chase.
In a Criterium if a rider is scheduled to rejoin the group after the alloted race time for that riders grade and after the 'laps to go' (e.g. 3 Laps to Go) call has been made then the rider will not be allowed to rejoin the race.
Another rule that sees some variations to standard Road Race finishers in a criterium is that in some cases lapped riders will be 'pulled' from the circuit. This is usually the case where a circuit is very tight and safety is a concern. In most races lapped riders will be 'pulled' from the circuit once the 'laps to go' call has been made to ensure that riders do not impede or assist the contending riders.
In some instances where a breakaway has occurred and there may be minor placings to be awarded to riders in the chase group the leading breakaway group may be left for a few laps while the chase group is given the bell for their final lap. They will then sprint for the minor placings. After this the leading breakaway will be given the regular 'laps to go' call. Again, this is done for safety reasons and ensures that all contenders are given a fair chance of placing as well as ensuring that the recording of places can be made accurately.
So in recap:
A Criterium is a circuit race based on a duration of time plus a few laps and a rider who falls or has a 'recognised mishap' may take a lap out. Any other mishap that occurs means that they must chase back to the group. The Criterium circuit distance is limited to no less than 800m and up to a maximum of 3km.
All other Road Races are usually distance based races (except a Kermese) and there are no laps out, or early turns (if the road race is on an 'out and back' or 'loop' course).
To find out more please check out the Queensland Rules on the CQ Website. Remember it is the riders responsibility to know the rules - Not the Commissaires to coach you, guide you or give you a break because you didn't know. If you want rules explained please contact a commissaire in your club and they will be more than willing to explain the rules to you away from the race and without the pressure of running a race at the same time.
Some tips on criterium racing have also been published on the cyclingtips.com.au website. See link http://cyclingtips.com.au/2012/10/golden-rules-of-crit-racing/