Good point.
While most new racers start like Sean did -- converting their street ride to race use -- prospective riders should at least consider buying a cheap, used race bike as an alternative.
Depending on how competitive you realistically expect to be, you can often find a prepped, 5-year old 600 race bike for $2-3,000. Then, you already have the exhaust, suspension bits etc that you will need soon anyway, plus if (when) you crash, you don't
[email protected]#k up your street ride.
The other thing to look at, depending on the classes offered locally, is smaller-displacement and/or singles/twins classes (bikes like 250 Ninjas, EX500s or any thumpers), or, if you are not afraid of a little wrenching, 125 gp bikes. Bikes are often available fairly cheap, as riders move up to faster classes, the bikes are easy to work on, easy to learn on and often the race fields are less crowded -- and fewer testosterone-overloaded squids thinking they will score factory rides in their first season racing;-)