700 Yamaha Grizzly - won't start but was able to start it with ether. Runs fine and starts when hot. We have changed the battery, start solenoid changed and sparks check and they are good. Start solenoid flutters (starts on/off, on/off) and then eventually when start switch is depressed enough times the starter and solenoid will engage fully but very slow to crank at first. THen will pick up regular cranking speed. Any suggestions???

SOURCE: 91 yamaha fzr engine turns but wont start

the floats in the carb are stuck. you can try lightly tapping on the carb with a screwdriver that should do the trick.

SOURCE: Yamaha 2001 Raptor 660, sat for a year, wont

Your gas is bad.  I have to change my all the time If your starter turns but dose not engage the starter barring is out DO NOT BUY STOCK. buy after market when you replace that.  they 

SOURCE: 97 fatboy starter engages but will not stay engaged.

I would check the starter clutch its self first. It is a one way clutch so if you remove the starter and disassemble it to the starter clutch and hold the starter clutch in one hand and use your other hand to turn the starter clutch gear, it should only turn in one direction.

SOURCE: Yamaha 2001 Raptor 660, need to clean my carb

Drain and replace the gas with fresh.
Remove the air cleaner and spray carb cleaner into the inlet. Work your throttle a little then put everything back together and try to start it.

SOURCE: Troubleshooting starting system on 2000 yamaha waverunner

check the starter relay switch