05 CRF250R Bad rattle/grind noise

[B0000M]

we reckon we've found it - the bearing inside the right side cover on the shaft goes through to the oil pump, got heaps of slop in it.

the bike got ridden for a few hours today at the pumice blast and hasnt got significantly louder.

something to do this week

[Taz]

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!$$$

Get the big bore kit for it. 280cc Both Eurobike (Atthena) or Whites do them for around $1100. Thats piston, rings, gaskets, pins, clips etc Whites also do aftermarket standard barrels for $495.

[vr4king]

Good idea i rode one the other day a 280 that is,man all power all down low can chug out off anything

[crazyxr250rider]

You said you cheecked every bearing in the right cover.........I guess not.

[B0000M]

well heres the thing, i left that side up to the owner of the bike, i took it apart, he looked at it while i was doing something else....

[richyrich]

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!$$$

hi all,my son had his 04 shit itself with a collapsed big end,no warning.
i bought new crank from states thumpertalk oem(about 180 us)plus complete topend inc inlet valves quite reasonable and rebuilt motor myself.very easy
motor to work on once you get it out of the frame.

[telliman]

yeah, iv been into the shop a couple of times this week to look and have been reading heaps in my work manual and am not so scared by the inside of a 4t any more!

[B0000M]

ok, so we replaced the shitty bearing on the balance shaft- still rattles.

any more ideas before we split the cases?

[barty5]

ok, so we replaced the shitty bearing on the balance shaft- still rattles.

any more ideas before we split the cases?

possible the other bearing on the other side of balance shaft is just as rooted load would have transfered ova to it from the one you have already done.

[B0000M]

possible the other bearing on the other side of balance shaft is just as rooted load would have transfered ova to it from the one you have already done.

nope, it feels good and wasnt subjected to shit gritty shit oil that the other one was. took the shaft right out to do the bearing.

[B0000M]

progress has been made, ran the bike for a couple of seconds today with the gear that is on the balance shaft which connects to the primary drive off- rattle gone.

this is the shaft that DID have the shitty bearing.

turns out the bearing being chewed out with so much play has caused the balance shaft to move around a bit which in turn makes its gear not mate properly with the primary drive gear- therefore hooking the teeth slightly making for a sloppy mesh, making a massive rattle.

now just waiting on prices for new primary drive and balance shaft gear (32t)

[kezzafish]

Man... what a palava. well done

[cheese]

That will be expensive!

[xwhatsit]

Are sloppily-meshing PD gears that big an issue? Hell, people used to use chains for years. Now it's properly aligned is it that much of an issue that there's a bit of play in the gears? Sure there'll be drive-train lash, but that's not the end of the world off-road?

Unless, of course, by having a bit of lash in the gears you're likely to have catastrophic failure later on.

[B0000M]

its not likely to do anything any favours- but at the same time id say it has probably at least another 20 safe running hours..

sounds shit as tho