Andy! Hey, somebody's got to live the dream! Anyway, that's what employees are for! It's all about being a good delegator.

PatrickOT - Very interesting about the flush. I'm glad to hear that somebody has done it before. One (or two) side question(s): how did you get the bike back to civilization in order to do the flush? Or do you always travel with 5 liters of diesel fuel and 2.5 liters of oil just in case you tip over in a river crossing?

Thanks tons for your input guys. Well, MollyD, the hammer didn't work so I'm going to try something else.

Just a few side notes. It's a 2002 KLR650. The piston cracked between the first and second rings and was welded and machined down as good as possible. The problem began about 8.000 km later - just about enough time for the weld to start breaking apart. Every oil change the oil filter has lots of silver and black particles. The oil gets really really dirty more quickly than it should. I was using Castrol GP 20/50 mineral oil. (Just switched to Castrol semi-synthetic, which should give me a better range before having to change the oil again.)

About 1.500 km after each oil change, and the bike running perfectly with tons of power, it just dies. From one moment to the next it looses all of it's power and dies, literally. From running at 100km/hr, to the engine dying, but it's still in 5th gear, so it slowly slows down to a stop. I usually try to use the momentum that it has and release the clutch to push-start it, to no avail. Once we come to a complete stop, I try starting it for a few minutes without any luck. I turn the key off every once in a while and let it sit, then resume with the start button. Eventually it will fire and run perfectly for a few kilometers (sometimes until 10 or 20km), and then die again in the exact same way. After 3 or 4 of these episodes it won't fire again until I change the oil and clean the filter - then it starts up like she was new and runs perfectly for about another 1.500 km or so.

So to recap: the problem started after a piston weld. Now she runs perfect after every oil change, until the oil looses something of it's viscosity, then the problem returns. I change the oil and the problem goes away, temporarily.

For me, the problem is definately oil/particle related. I'm going to try to diesel fuel flush that PatrickOT used, and see what happens. If that doesn't work, I'll try some of the other suggestions.

It's pretty late here and I've got another long ride tomorrow, so I'm going to hit the hay right now.

Don't worry guys, I'll get back to you to let you all know how it all turns out. What I try, and what (hopefully!) fixes the problem.

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