KDXRIDER.NET

It appears i'm having some trouble with my kdx 200 2002 model. 5 days ago I got all my mates ready for a ride that would separate the boys from their bikes of course. I started her up, first kick no problem, got 1km down the road when I heard this big noise in the engine. My heart stopped as I came to a stop it really sounded like I put the conrod through the block somewhere but I am starting to believe that was my heart knocking my chin shut . Being a couple hundred meters away from my first stop I thought it would be safer to push there then asses the damage. First was spark plug out and there was nothing physically wrong with it, so I pulled a new one out the bag put it in then fired it up. first kick again. It idled for a whole 5 seconds before dying out and the motor locked pushed back home, took top end apart only to discover I had 3/4 of a piston. The other 1/4? well that was in my header and locked between the crank and casing:mad: luckily no damage to the barrel, a few alum smudges but nothing a light hone couldn't fix.. Anyway, back on topic. Ive now managed to get new piston and rings etc. All assembled and the time to start it up came it started first kick then died a whole 5 seconds later :evil:Another new BR8Es in and after approximately 65492 kicks it started again, ran perfect on idle for about 2 mins before dying out put another new plug and after almost 3000000 kicks my accelerator cable snapped. Approximately 2 kicks after the cable snapped my kick start broke clean off so I decided to ask for help to try and figure this out while fixing kickstart. Im a mechanic so im familiar with this stuff but this one has me confused

You may have cracked the case when the chunk on piston skirt got wedged between the case and crank. Not sure on the bikes, but this is a common issue on the 2-stroke jetski's when a piston breaks it punches a hole in the bottom of the crank case. I think you are going to have to do a complete tear down and split the cases.

Yeah, after that piston shattered, the cases should have been split and checked. You probably either still have pieces of piston down there, or damage to the case halves.

this is what I am worried about. I did inspect the crank case thoroughly, I pressure cleaned the inside for a good 20 mins to get everything (if anything out) then a complete flush with some pre mix. if there were a hole in the crank case it wouldn't have compression, I put a psi test and its perfect so no holes. I decided to take the head off and it appears I had a small leak in my head gasket. time to replace and check my jetting out again. Thanks for the feedback guys

Hi. When you said a quic hone, is your cylinder sleeved? Stock is plated and honing is a big no no.

SmokingGreen wrote: if there were a hole in the crank case it wouldn't have compression, I put a psi test and its perfect so no holes.

compression test is reading the top end only. Remember, during compression, the combustion chamber is sealed off from the crankcase by the ring seal. You'd need to do a leakdown test to check for a leak in the bottom end.