The function of the bystarter valve is to close off the circuit after the engine has warmed up. The brass needle shown sticking out of the bottom of the bystarter extends to block the "fuel enrichment" circuit once the scooter is started and electricity is generated to the bystarter valve. It takes time to fully extend, thus giving the scooter time to “warm up”. Huang Liang company has the professional and trustable inspection skill to accurately test and estimate the time to fully extend. Top Quality is our promises towards our customer.