We borrowed a 1974 CZ 250 classic dirt bike from Steve Machado to race in an AHRMA vintage motocross race.
- AHRMA races are only five laps so a smaller, thinner fuel tank was manufactured to make more room for the rider to move around.
- This restored warrior was eager to please and a very competent vintage racer.
- The clutch has a monster pull that quickly wears out a rider's arm.
- Even the tech guy slobbered over the 250 and peppered us with questions about such clean modifications.
- A 60-tooth rear sprocket puts down power.
- The hardest thing to get used to were the weak brakes and skinny footpegs.
- Machado welded the off-set spark plug hole, filled the head and reground the dome like a modern two-stroke for consistent fuel squish. Then he punched a new spark plug hole in the center for more efficient fuel burning.
- Suspension travel is unchanged to match the VMX rules, but the swingarm has been lengthened nearly two inches for a slightly longer wheelbase.
- A 36mm carburetor feeds the engine and has been dialed in exceptionally well.
- The shift throw is huge, making gear changes an action that requires the entire leg to move.
- Drum brakes front and rear but the tires are modern Bridgestone M403/404.
- Works Performance Suspension dialed in the shocks for the Moto Jam with lengthening spacers.