Posts: 35
Joined: 5/4/2014
Location: GBR
Edited Date/Time:
Picked up an rmz 250 2008 for cheap, it had an engine noise. First thing I did was drop the oil, check all filters and valve clearances. 3 valves were on the loose side and one tight, all sorted and in spec now.
Below are 3 videos of the bike, before I dive any deeper I would just like the opinion on others as it could be something simple...
Posts: 522
Joined: 2/17/2017
Location: Ravenna, MI USA
Posts: 1731
Joined: 8/25/2015
Location: Mansfield, OH USA
Check cam chain and tensioner and guides. If that checks out okay id pull the head off and see what the internals look like. Definitely wouldnt run it till you find it.
2009 Kawasaki KX450F
2009 Kawasaki KX250F
2002 Suzuki GSXR 600
Posts: 1693
Joined: 12/6/2014
Location: Ridgecrest, CA USA
Might be something simple but my opinion would be to tear it down immediately ....we had an 09 crf250 and it developed a slight noise , not as bad as yours, but ended up needing complete rebuild including bottom end...a rebuild at this point wont be too bad since it hasnt grenaded . You mentioned you picked it up cheap...i would just plan on a rebuild and now you can start with a clean slate and be comfortable knowing whats been done to it. When you get to that point, pm me, i will save you some $$ on parts.
Posts: 942
Joined: 9/7/2012
Location: MA, USA
Any idea when the last top end was done? Replace the cam chain and reset the tensioner; your bike sounds like my friend's sxf250 that grenaded shortly after. The cam chain had jumped because he didn't replace the chain or reset the tensioner. Dropped a valve and that was it for that motor haha
If you're not mixing gas, you're not haulin ass.
Posts: 35
Joined: 5/4/2014
Location: GBR
Edited Date/Time:
Thanks for all the replies, I decided to dive into it today and just strip everything so I'm sure.
Crank is spot on, no play anywhere
Right side casing is all fine including clutch / primary gear ect
Piston looks good considering I do not know the history I would be happy to continue using it (I'm planning to sell the bike on anyways!)
Cam chain guides look ok, I don't think they are too worn.
The timing chance to me seems quite loose! It hasn't jumped since I've owned it (test rode for approx 2minutes) and had a lot of start/stop and revving trying to diagnose issue but has not been lapped around a track or anything.
I have a video of the chain here:
Posts: 684
Joined: 12/24/2011
Location: Benton, LA USA
Put the engine at TDC and see where the cam gear marks line up. That will give an idea about the cam chain.
I would replace it as you are not sure of it's history or age. The same with the piston and rings. Yes you will need new head and base gaskets.
Paw Paw
Posts: 942
Joined: 9/7/2012
Location: MA, USA
Does the bike have a manual or auto tensioner?
If you're not mixing gas, you're not haulin ass.
Posts: 532
Joined: 4/1/2008
Location: PA, USA
The chain should not have that much playing in it. Could be the chain is stretched and tensioner is fully extended and not put enough pressure on it also don't reuse the gaskets.
