Transitions are the least practiced or thought about part of triathlons. Many consider T1 and T2 as the fourth discipline. (You can argue there are a total of five including the swim, bike, run, transition, and nutrition.) Practice your transitions once a week in the month leading up to your first race. You should be doing a speed block anyway, so this might fit in nicely for your weekly brick workouts. This alone may give you more free time/speed than $2000 wheels.