25+ vet A and vet B or 40+
prefferably the 85cc class
if he is just starting then 250 beg
125 or 250 if you fit on the but but they run together in the 250 class
They would have to be in a 90 cc class or lower to race quads. But you can be any age to race dirt bikes.
85 cc or 150 cc
65cc 85cc supermini
Depends on height and weight.
125, 250, 450
I don't know that it is the most important race ever, but what stands out in my mind is the 1981 Motocross DES Nations where Team USA won completely unexpectedly and brought on a 13 year domination of the MX Des Nations by a country, up til then, considered to be inferior in motocross. daytona supercross is always the best race and atlanta 2009 supercross is the best race in history
ive been tring to get into motocross racing for a long time. next year hopeffully but it is very expensive. your looking at around $500 - $1000 to race for a season
it depends on what place you finish and your sponsors
about $600 - $6050 all the gas and race fees