My 2001 cr250r has been my most reliable bike but recently my son rode it and now it won't start.
he started it and rode it but as the bike was warming up it would bog at high rpms then it went away once the bike warmed up completely and was fine for the day but after it cooled down again it wouldn't run without the choke on. We then replaced the spark plugs twice and took the carburetor out twice but no signs of fault. Then tried to start and it wouldn't even spark and spark looked extremely weak when we looked at it. Day later was checking grounds and cleaned some stuff up and touched things and now it sparks but doesn't try to start.

Any help is appreciated, thank you