I bought this 2000 CR250 at the beginning of the summer and it has ran great the whole time I have had it. I've had the spark plugs fail up once on me but only because of my fault. Other than that nothing wrong with the bike, I've even dumped it on the track once already breaking my hand but it kept on running. Well suddenly the other day I started having issues getting started and for about 2 - 3 weeks now the only way I can get it started is by taking out the spark plugs spraying starting fluid on it and putting them back in. Any ideas on whats going wrong as well as how I can fix it?

 

sounds like a compression issue.

 

Lots and lots of maintainance is mandatory with a dirtbike. How is your air filter: clean it often? Grease the contact edges?
What kind of premix oil do u use? At what ratio?
Have you taken the top end off the motor just to check things out? A lot can be said about what you see there.