[kfx700_ryder]

Just picked up a 2002 650 for dirt cheap. It had 564 hours and 1500 miles on it. The owner told me that it started pinging sound and he just shut it off and left it parked. Anyways...heres what i know.

Bike starts easy
pinging/knock is there all the time
Clutch has been removed and the knock is still there
oil was a little low, but not more then a 1/4 quart
Motor was not run for more then a few min with the knocking/pinging.

Is this most likely a crank bearing? Im figuring thats what it will end up. Should I replace the crank? How can i tell if the crank is damaged? just looking for some places to start. im going to tear the engine down myself and do the work so a shop doesnt have a field day with me. I just thought if i posted my symptoms it may lead to a general place to begin. Im going to drain the oil and check for metal shavings and also remove the filter. Any help is greatly appreciated.

 

[mr.stevo]

1997 prairie 4+4 400

wats up man i think i have the same prob... but Iknow what caus it...
Yester day i was doing some donuts and she started ping and clunking ...
you know the sound... so i am also woundering what to do?

 

[Camo Joe]

oil

Drain the oil and check it and the filter........see if it has metal flakes etc. in it. If it does you know what that means...............

 

[crazy650]

Drain the oil and check it and the filter........see if it has metal flakes etc. in it. If it does you know what that means...............

deff do that if you find any in there time big bore kit! and a mechine shop

 

[kfx700_ryder]

probably a dumb question, but if the crank bearings go, can it do any damage to the case...etc? If its simply replace the crank, bearings, pistons..etc I can do all that myself. Im going to drain the oil this evening and see what i find. Ill prob cut the filter in half as well. I appreciate the help guys.

 

[mr.stevo]

Yah i mite b a boat mac but some of the guys on this site are full of shit....... But dont go ording a pistol and jug... Compresinc check .. Troble shoot it where is the sound from ,motor,tranny [email protected], first find out that.. Thes guys told me the same thing..my atv problem was cluch @belt.... So..... Dont just throw parts at it and think u will fix it......

 

[PrairieDragRacer]

Crank bearings suck. That's what ate my old `02 650. I fixed it the first time, the shop said the crank was good........ 4 months later, it ate it's second bearing. Replace the crank. Also, if you are doing the work yourself, then you might as well bump your compression and get a set of cams. Unless you are power hungry like 90% of this site, then BBK time. How deep are the pockets?

 

[PrairieDragRacer]

Yah i mite b a boat mac but some of the guys on this site are full of shit....... But dont go ording a pistol and jug... Compresinc check .. Troble shoot it where is the sound from ,motor,tranny [email protected], first find out that.. Thes guys told me the same thing..my atv problem was cluch @belt.... So..... Dont just throw parts at it and think u will fix it......

He said that it made the noise with the clutch off.

That's what mine did. It was the crank bearing.

If I could hear a clip of it running and making the sound, then I could better tell. Also, mine made a higher pitched noise when revved, on deceleration.

 

[kfx700_ryder]

pockets are pretty deep for this project, but im not sure which route im going to head with it. This bikes mainly going to be used to do some hunting and play around when its sloppy out. Im going to replace the crank while im in there just for piece of mind. I figure if it spun a bearing it most likely scared the crank. Im hoping to have the motor out of the bike in the next couple days. thanks again for the help. ill post up what i find.

 

[drifter]

Yah i mite b a boat mac but some of the guys on this site are full of shit....... But dont go ording a pistol and jug... Compresinc check .. Troble shoot it where is the sound from ,motor,tranny [email protected], first find out that.. Thes guys told me the same thing..my atv problem was cluch @belt.... So..... Dont just throw parts at it and think u will fix it......