In the final article of his two-part series, PPM's Richard Hartley Jnr talks about the relationship between speed and weights in racing-and adds to your knowledge with a helpful chart.

In certain races, weight can be a 'Key determining factor. You always have to consider the weight a horse has to carry though it is less important in some races than in others.

The punter should certainly remember the differences regarding age and sex shown in the weight-for-age tables. The main reason why weight is sometimes important is that too much weight can seriously affect the racing ability of a horse. A truism? Sure, but it's a point that has to be stressed, and stressed clearly.

Carrying 55 kg, a horse may be able to run 1200m in 1m 9.3s with a time at the 400m mark (after 800m) of 45s flat. If the same horse had to carry 56.5 kg--only 1.5 kg more-it might still be able to run the 800m in 45s flat, but it might require as much as 1m 11.1s to run the full distance. That 1.5 kg extra weight makes all the difference in the testing final stages of a race.

Other better-class gallopers might carry the 56.5 kg with no appreciable problem, and this only points up that an ability to carry weight, and still run well and consistently, is a vital measure of a horse's class.

My research shows that not all horses are affected by adding, or removing, weight in the same manner. Each galloper, in any class, has a PEAK of weight tolerance over different race distances.

Horse A can carry up to 54.5 kg without difficulty at distances from 800m to 1300m. At 1400m to 1700m it can carry 53.5 kg and at distances to 2000m this horse can carry 52 kg without being seriously affected in efficiency.

The fact that weight has been taken off a horse (in relation to its last race) will not always improve its chances of winning. Consider Horse As ability/weight graph-if it dropped 2 kg, carrying 52.5 kg instead of 54.5 kg, we would not expect as much improvement as we would if it carried 54.5 kg rather than 55.5 kg, a mere 1 kg difference.

In the same way, the fact that weight has been added will not necessarily seriously harm the horse's racing ability. Horse A would pick up 1.5 kg going from 52 to 53.5 kg with little or no trouble. But the 1.5 kg from 54 kg to 55.5 kg could cause it to fail in a race.

In some races, strong chances are weighted beyond the limits of their effectiveness. This allows longshots to sail in. Punters who know the score can usually determine by studying past performances whether a horse can be expected to go the distance while carrying its assigned weight.

If the horse is too heavily weighted, and the odds such that the horse offers little or no value, it's always wiser to go to the second choice, particularly if that horse is at good odds.

So, now to the speed factor: My check of my racing research shows that in about 200 races, in all classes at varying distances, the winner was in front after 800m in 25 per cent of the races if the fractional running time to that point was 46s or slower.

In 15 races, the leader ran the first 800m in faster time-anywhere from 45.8s down to 45.2s-and stayed out in front to the line. But in races where the pace was even faster the leaders didn't fare as well. In 13 races, in which the pace for the first 800m was faster than 45.2s, the horse which was leading at the 800m wasn't there at the finish.

The pace, then, was too fast. It simply took too much of a toll on the leader. Pace is the real foundation upon which the pattern of a race is built. It has prime influence on the final running time for every race and it affects the chances of each runner.

The speed at which races are run, then, is a variable factor. The punter never knows before a race exactly how a race will be run. You can, though, work out the times for all distances and thus average that a horse roughly covers seven times his own length in one second.

Seven lengths in weight is equal to 10.5 kg (using 1.5 kg to a length) so one second in terms of weight is equal to 10 or 10.5 kg.

The following timetable explains it all:

KgSecsKgSecsKgSecs
0.5.053.5.406.5.75
1.0.104.0.457.0.80
1.5.154.5.507.5.85
2.0.205.0.558.0.90
2.5.255.5.608.5.95
2.5.306.0.659.0 1.00
3.0.356.0.70

If you use these figures it will be as close as you can get to the actual situation. To estimate lengths you can, using these statistics, always allow 1.5 kg to be the equivalent of a length and so a horse beaten 4.5 lengths has finished about 0.50 seconds behind the winner.