Join Date: Dec 2008
Motorcycle: Track - 99 SRAD 600, Street - Blue/White K8 750
Re: Going from synthetic back to conventional?
All you guys are wrong, switching from a full synthetic oil back to a conventional oil. Causes oil sludge. Mind you, if you have been running a Full synthetic and switch back to a conventional oil and you stick with the conventional oil, you're fine. But, switching back and forth constantly could cause enough sludge to cause some problems. You would have to change back and forth consistently for a long time to possibly cause any problems, as a result from oil sludge. If you switch back and forth once or twice it's harmless. The reason it is warned not to do is, the chemical structure of the remaining oil in the motor ,from say full synthetic, is mixed with the new batch of convectional oil. It causes small amounts of oil sludge. But, doing it once or twice over the life of an engine and changing that oil at proper intervals, no foul. The best thing to do for sludge prevention is to have your motor flushed. All motors after a given time are subject to oil sludge. It takes a lot of miles for this factor to possibly be a hinder on a neglected motor. Believe it or not, the best thing to flush a motor with is diesel fuel. Poor it in any crankcase after draining oil. Say five quarts of diesel in a five quart crankcase. Start the motor, let it idle ( DO NOT REV ! ) for 2-3 minutes and no longer. Drain, like you would oil. You would not believe what the diesel removes, that was left behind. Would I do this on my 11 thousand dollar motorcycle ? Hell no, but have done it on every single vehicle in my life, during every oil change. A lot of miles, out of a lot of vehicles.