GY200 "BOGGING DOWN"
 

My GY200 stars to "bogg down" or slow down beginning at speeds of 60kmh (50mph). I have changed the plug, cleaned the air filter which did not help at all and the problem is getting worse....it's occuring more often and more severly. It starts and idles normally and seems to perform normally at 30mph. There is a tube with a rubber extension on the exhaust section of the motor which seems to be some sort of polution control. The rubber tube had rotten and as a temporary measure I had blocked it to stop exhaust noise and drove like that for a day until I could find some proper hose. Could it be that temorarily blocking this hose has caused this problem? Has anyone got any ideas as to what is going on and how I can fix it?

Try to loosen the fuel cap and let a bit more air in, to be sure don't have a partly blocked vent.