05 CRF250R Bad rattle/grind noise

[telliman]

my piston skirt cracked and tilted and has shat the barrell, also a bit of play in the conrod so new kit as well as new barrel and piston!
am awaiting the painfull part!$$$

[B0000M]

ouch, thats not going to be cheap.

so glad i own a 2 stroke, nice long piston, id like to see that fucker tilt!

[cheese]

Hmm my final sugestion is to try the bigger hammer.

My god long live 2 strokes!!

[telliman]

should have followed my instincts and got piston done and freashend up when i got it, will put it down to a leason well learned!
on the bright side ill have a brand new motor next week!
suspension will have to wait.

[B0000M]

im just hoping for my mate's sake that this is the problem and not something else

[crazyxr250rider]

If its not the primary drive or clutch it sounds like your describing severe piston slap, also check the Little end for play...

[telliman]

$2200 all up!
oouueeeech!

[crazyxr250rider]

I did 2 Full engine rebuilds for less than that....

[theblacksmith]

aside from the piston having wear marks downb the skirts, i had a thought that if the piston is tilting in the bore, this would make it harder to turn over with or without the plug in, and with the piston out the crank turns easy as, so somewhere in the cylinder there is friction happening, as the cam turns easy buy itself - (when its not trying to push a valve) and the crank turns easy without the bore, so i think im on to something

any thoughts?

Hmmm - piston slap/tilt??Makes sense if its right through the rev range. The bore is all good you say? Hopefully youve pulled it apart before it was to late.

[theblacksmith]

aside from the piston having wear marks downb the skirts, i had a thought that if the piston is tilting in the bore, this would make it harder to turn over with or without the plug in, and with the piston out the crank turns easy as, so somewhere in the cylinder there is friction happening, as the cam turns easy buy itself - (when its not trying to push a valve) and the crank turns easy without the bore, so i think im on to something

any thoughts?

$2200 all up!
oouueeeech!

Oh dear! I think thats what I paid for my KDX all up.

[B0000M]

just playing with the pieces in my hands last nite, i can make the piston wobble in the bore on the axis that it shouldnt and make it rattle like that, so if i can make it rattle by hand im sure it could make itself rattle with compression and a conrod pushing and pulling it from side to side as they do.

heres hoping it this top end rebuild fixes the issue. if its not that i dont know what it is,

also checked the oil pump last night and all lines, all is well ther short of splitting the case and visually checking the pump but its a mechanical gear-meshing type of oil pump so theres not much that can go wrong there if its still turning - if something had gone wrong in there it wouldve stripped the plastic drive gear for the oil pump before it did anything else - which it hasnt.

[kezzafish]

You're on to it mate, piston will be it. Well done and your mate owes you big time for saving it

[xwhatsit]

If the piston is wobbling around in the bore then that must be it -- you reckon you did it when you filled the bike up with mud?

If so, time to get the plastigauge out and check cam bearings, check little end/big end, all of those kinds of things. Save something more expensive later

[B0000M]

new top end in earlier, still knocks. doesnt seem to be geting worse, he's guna ride it on sunday anyway and see what happens

[crazyxr250rider]

Did you check the Little end for wear???Could it be the Big End????????Are you just being paranoid about a noise that isnt there????Does The rattle go away when you put your hand over the clutch cover???