My bike is a Yamaha scorpa 250 trials...i been riding it fine only until I parked up and washed it now the next day it won't kick over ... anyone know why please 

Check air box for water, were you using a pressure washer ? If water in air box, remove spark plug and try kicking over.

When you say it wont kick over, do you mean its seized, or it kicks over but wont start?

 

Not jumped into gear has it? Go with the spark plug removed and turn the engine over slowly. If its water down the bore you need to remove as much as possible before running engine. Check the airbox it may need sealing to prevent further water intrusion.