Yamaha trouble shooting

Clogged fuel petcock or dirty fuel filter.

hi mate, i have a 2008 yamaha yzf r125. it has a 13.8 litre tank or 3 gallons. i do 300 to a tank. so 100 miles per gallon. that riding no faster than 50 mph. hope that helps mate.

Hi,

Pipe bluing indicates that cylinder is running lean, therefore too hot. Have you looked at the front spark plug? The insulator should be paper bag tan. Ash white and it's running lean.

The idle going high can be a vacuum leak. You can spray WD-40 (or propane) around the intake flanges when it's running, and if the engine changes speed, you've found the leak.

You might consider contacting Yamaha Motor Corporation, USA - customer relations (800) 962-7926, press "1" for Star Specialist. See if they would consider either exchanging the bike, or sending a factory specialist out to examine your ride.

The float is stuck open. Clean the carb.

The carb/s are flooding , you will have to check the float pin and the float, a good clean with compressed air should do the job, check too the fuel line and the fuel filter.
Hope this helps!