Tuesday, November 30, 2010

This could happen if you misplace your key.

Monday, November 29, 2010

Tuesday, November 9, 2010

49cc Scooter Hard To Start

I have 2 49cc Chinese scooters with +- 1700 miles. I have had the same 2 problems with each. I mostly ride on dirt county roads and have learned that if the air intake screen gets even slightly dirty the engine will run very, very sluggishly. The screen and filter must be kept spotless.
The other problem is a loss of the vacuum necessary to 'suck' fuel through the carburetor into the chamber. Vacuum is lost by a bad vacuum hose or misadjustment of the upper valve tappet not allowing the valve to close completely on the fuel intake stroke. I have replaced the hose leading from fuel tank pitcock (located on bottom of fuel tank) to the port forward of the carburetor. The vacuum from this hose opens the tank pitcock allowing fuel to flow to carburetor. Another reason for loss of vacuum is likely to be misadjustmet of valve tappet. After some engine wear, the tappet may need adjustment. I turned the tappet counterclockwise between 1/8 to 1/4 turn and the engine started almost effortlessly. An invaluable resource is http://all-shares.com/download/844398835-4-stroke-50-cc-service-manual-pdf.html  
Other than these relatively minor problems, my Chinese scooters (SunL MDL50QT-2) have been a dream to ride and maintain.  I have a supply of spare parts which I purchased off Ebay but have not had to replace anything so far.