Hey guys, I brought my WR450 to a mechanic friend to have it re-jetted with a JD kit and he did an oil change as well. When I got it back it ran better than it ever has and seemed good to go.
What I did not realize is that he did not drain both bolts when he changed the oil so the oil was overfilled. On a long off-road ride the bike started backfiring and running very rough. I noticed there was oil dripping out of the airbox all over the swing arm and when I opened the airbox it was coated in oil.
Brought it was back to him and he redrained the oil (correctly this time) cleaned out the carb and changed the spark plug which was black. The bike will start up and idle but the motor sounds very loud. The motor has always sounded very clanky but it is more so now. After the bike warms up for a couple minutes it will die out and wont restart again but will just backfire alot while cranking the motor over.
He says it may be a rod knock and need a complete top end job. Was this caused by the overfilling of the oil? Any help on how to fix it would be much appreciated. Thanks!
Edited by Mendo, September 05, 2013 - 12:17 AM.