The ratchet cam and the drive gear have small matching teeth on their facing edges that, when allowed to come together, permit the ratchet and driving gear to turn together in one direction only. When the kickstarter is not in use, a small ramp on the ratchet cam is trapped behind the kick starter stop bolt. This ramp pulls the ratchet away from the driving gear, thus preventing engagement of their teeth. When the kick starter lever is turned, it allows the ramp on the ratchet to move from behind the stop bolt. This permits the ratchet to move to the left and engage its teeth with those of the driving gear. The gear now turns as one with the kick starter shaft, and being meshed with a gear on the mainshaft, rotates the mainshaft, which in turn rotates the crankshaft through the clutch and primary drive. The teeth on the ratchet and driving gear are cut so that once the engine is started, the driving gear cannot turn the ratchet. If this were not so, the kick starter lever would continue to rotate while the engine was running. When the kick starter lever is released, the return spring rotates the shaft and ratchet back to their disengaged position. Because the driving gear is always meshed to the mainshaft, it continues to turn freely on the kick starter shaft while the engine is running.