my 2002 cr125 is eating spark plugs like crazy. im running 50:1 oil to gas ratio. its fine when its on the track but when i turn the bike off it wont turn on again. its like once the motor is off the plug instantly fouls out and wont spark anymore. any ideas? the top end has about 10 hours on it. and whenever i pull the plug after it fould it has oil on it.