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2005 kx250f ticking

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1 of our bike seized last year so I bought a used bottom end from an RMZ I believe, I thought they were the same. Put it back together and rode it for about 10 min before it seized again. This time the piston got worked so I bought a used top end,(piston and cylinder) that are in great shape. Assembled everything and starts up great and idles great but it has a ticking noise. Valves are in spec. I pulled it apart today to see if I could find anything deeper. Im not sure if this "port hole" should be covered by the gasket or not and if its an oiling issue. Basically now that I have a bottom end from ? Im questioning if the cylinder and head are right and flowing oil and should be on this bottom half? Ive gone CHEAP on this bike because it isnt worth much and by doing that I might have some parts that dont match? Here are the pics of the case and cylinder. In the pic with my fingers you can see where the gasket covers the hole. Is the gasket supposed to cover it? I know I shouldnt have put the used parts on too.

cyl1.JPG

cyl2.JPG

cyl3.JPG

cyl4.JPG

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After looking at my old bottom end it has the same hole so Im thinking this isnt the prob

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The gasket is correct wrt the port. The oil path to the head is, the oil comes up through that hole in the middle of the case, travels along the groove to get to the head bolts.  The oil travels up along the head bolts through the cylinder and up to the head.  There are ports drilled through the head from the head bolts holes into the head and it comes out under the cams.  You can see the bosses and plugs from this port drilling on the head and you can see those ports by looking in the bolt holes.  Blow compressed air through the cam hole ports to ensure it is clear and blows out through the bolt holes.

In your picture, you are missing the oring for the coolant port.  There is an oring that goes under the cylinder base gasket in the recess groove at the front right of the cylinder. 

The only thing is ... I really hate those flimsy paper green base gaskets.  They work great but in this case where there is an oil gallery, it presents potential problems.  The paper soaks, swells, and squishes into that oil port groove.  It swells and squishes into the bolt hole around the bolts.  These can restrict flow to the head. Chunks/flakes/fibres of edges of the gasket can come off and travel up the bolt holes to the head, plugging off the ports under the cams.  I always recommend you get a good stiff coated base gasket such as Comitec or other to eliminate this potential problem on this engine.

Hope that helps!

Screen Shot 2017-05-08 at 1.03.59 PM.png

Edited by FaceDeAce

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Ticking noise.  Really not enough description to go on there to provide much.  Could be normal, could be sticky valves, could be valve clearance, could be piston slap, ...  top end noise, bottom noise, muffler/header leak, ...

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OK,   sounds like valve taps. they also sound dry!  while you have it apart check and blow through the oil galleries as mentioned. Triple check valve clearance when put back together, use a lot of lube on assembly.  I use gear oil when putting my cams in.  Another is to really look closely at the valve springs.  Look for a broken spring or a noticeably soft one.  Easiest to do by taking them out.  Also, with the cover off like that you also will really notice just general valve and cam chain noise.  Try to decide if it is just normal or if there is actually something out of place.

Another mentionable which gets folks is:  exhaust header gasket leak.  There is quite a bit of pressure right at the head on each exhaust stroke puff.  A slight leak right at that gasket can surprisingly sound a lot like at tick when it is actually short bursting pipipipipiffs. 

 

 

Edited by FaceDeAce
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Thanks for the input. Im over working on this thing. If these suggestions dont fix it then its going to go sit in the shed and be used for parts. I ordered the comitec gasket kit so it should be here in a few days. 

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Ok, so just reassembled the bike with new gaskets, valve seals, exhaust crush ring and did not see anything of concern. I started it up and still F*cking ticking. Checked valves lash and 1 is at .008 and spec is .004-.006

Would this create the ticking by being out a couple of thousands?

So done with this thing!

Edited by flyn Ryan

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Ok. Well you replaced all that and I dont see shims listed. New seals don't mean ish if metals wearing. One of your intakes is .008"? My concern is why it's loosening. Not tightening. Cause you listed intake specs. (.004-.006") and your exhausts are .007"- .009". So .008" is perfect for an exhaust. Have you had your head off? I would've done a leak down test cause those years cylinder heads have longevity issues. Seats, guides, can be factors in ticking. Anything with this bike and running is valves. Re shim. Learn how to measure. Do it three times to be sure. Get a leak down.

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Ill have to learn how to do a leak down test.

Im at a loss whether or not the intake that should be between .004-.006 would cause the ticking if its at .008?

Yes, the head has been off and the cylinder is different as is the piston and rings.

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Different as in brands?
Dude that gap is huge.
And I doubt you knew that gap months ago. Is It getting bigger? Measure. Reshim. And ride. I dont think you realize how much a thousandth of a mm is to a motor.
So YES...IT IS AN INTAKE AT .008"? The left one?
You've said nothing about adjusting valves. New ish is not an adjustment. You cant see .001" with your eyes...get feeler gauges, a vernier caliper, and a shim KIT. Not just one shim unless you're confident on your math.
Now don't say again ''it wont work. Until BOTH INTAKE VALVES ARE AT .005" and BOTH EXHAUST VALVES ARE AT .008". THEN you'll narrow your search
Take head off. (A new gaskets good, if its new unfired then reuse it. Pour gasoline into the int or ex ports ONE AT A TIME. The valve should hold it in the port. If it leaks out the valve then you're leaking. Do each valve. One at a time. The problem with these valves if you can't lap them. These heads need $500 at brand new nontheless $500 10 years later. This bikes valve train is like stale bread
Go steel or get ready for year after year of this same issue.

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