S40 Blvd Stalling
 

My wife has a 2006 S40. When she gets out in the morning, after warming it up, the bike will tend to stall when she comes to a stop unless she keeps the throttle up manually. The other thing that she found that helps is turning the fuel petcock to the standby position instead of the main position. I know that this position uses a lower standpipe and bypasses the vacuum shutoff feature of the valve. Any help with might be the problem and some things I should look at would be greatly appreciated.