400man
08-07-2009, 09:27 AM
I was riding my 400 the other day on my trails and it started ticking alot louder than normal, ticked for about 5 or 10 seconds and then the bike just shut off. I was riding down a steep hill climb in 2nd gear with the clutch out, using the engine as a brake when it started ticking and shut off. at the bottom of the hill I tried to start it and the starter would spin but it wouldnt turn the motor off and it would roll easy in gear.
so I get it back to the house and pull the clutch cover and see that the timing chain had jumped off the crank shaft. pulled the top valve cover and seen that its still on the cam and everything looked normal. so next I pull the cam chain tensioner and it looks like its shot. doesnt seem to hold any pressure. I guess I got lucky that it didnt tear up anything. and since im into the topend Im replacing the tensioner and timing chain as well as putting in some new rings and hone job and valve seals and cleaning the carbon off in the head. the bike is a 2000 model and it looks like the motor has never been touched inside, all original. I measured the piston and bore and its all within spec and the piston still looks good.
so I get it back to the house and pull the clutch cover and see that the timing chain had jumped off the crank shaft. pulled the top valve cover and seen that its still on the cam and everything looked normal. so next I pull the cam chain tensioner and it looks like its shot. doesnt seem to hold any pressure. I guess I got lucky that it didnt tear up anything. and since im into the topend Im replacing the tensioner and timing chain as well as putting in some new rings and hone job and valve seals and cleaning the carbon off in the head. the bike is a 2000 model and it looks like the motor has never been touched inside, all original. I measured the piston and bore and its all within spec and the piston still looks good.