http://www.scootertime.net/viewtopic.php?f=39&t=954
Yamaha Razz Service Manual (found through Google and another WikiAnswer question) http://www.mediafire.com/?xibwfty2mtj Also available at http://scootertime.net .
Here's a link for the Razz repair manual-http://www.mediafire.com/?xibwfty2mtj
Try replacing your current 2 stroke oil with 100 percent synthetic 2 stroke oil. Available at any motorsports dealer. Worked for my Razz. Has not smoked since.
If gas is leaking from a Yamaha Razz muffler, then the float may not be set correctly. This means that it is not shutting the intake off.
2 places
.039-.043
There are several reasons why a Yamaha Razz may quit running. These include issues with the engine, its age, issues with spark plugs, lack of gravity, lack of oil, lack of gas, etc.
Does it run on choke? Is it starving for fuel, if so is the needle valve set for the float?
Bad needle/seat valve on carb.?
10th digit of VIN is always model year; use common sense to determine decade.
It can go upto 45km per hour depending on weight and weather, which is about 72 Km an hour.
there is a little screw on the back of the carb. if you loosen it, it will idle slower, tighten it, it will idle faster.