You should be able to find a head for cheaper on ebay or what not, rockymountain should do you good for the other parts, valves, seals, could possibly reuse the springsI've got a manual on the computer, I'll see if I find anything there.
I see! This might be obvious once I take the rest of it apart, but how do I tell the coolant lines apart from the oil lines? I suppose the oil have much smaller holes?
Silicone, as in, this was caused by silicone?
Yeah you tell me.. the dealer wanted about 600 USD for a complete head excluding the cams, which is almost half the price I bought the bike forI'll see if it's possible to buy a head excluding screws and valves and all that, and just transplant it. Or find a used one somehow.
RM-Z250 Oil starved cam journal? How bad?
- Thread starter JoniX
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I've got a manual on the computer, I'll see if I find anything there.
I see! This might be obvious once I take the rest of it apart, but how do I tell the coolant lines apart from the oil lines? I suppose the oil have much smaller holes?
Silicone, as in, this was caused by silicone?
Yeah you tell me.. the dealer wanted about 600 USD for a complete head excluding the cams, which is almost half the price I bought the bike for
When you blow air thru the oil passages to check for any restrictions you will be able to clearly tell where the oil galley ports are from coolant.
I couldn't see those pics well on my phone, but run your finger nail across the width of the cam journal, if you feel anything but smooth the cam is shot.
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Problem is I live in Sweden, importing a head will be as expensive as a new one
I've been trying to google local used parts dealers, but to no luck so far.Hmm, so the valves and seals shouldn't be reused?
Aah I see!
I wasn't paying much attention to it, but I did try the fingernail when I first removed the cam, and I think it felt pretty much smooth.
Exhaust valves rarely
As a general rule of thumb, exhaust valves usually don't cause a lot of problems in these bikes, its almost always the intakes. If it were me, unless the intakes were brand new, I'd go ahead and replace them, the springs and seals.
It all depends on how they pass the specs listed in the manual.Problem is I live in Sweden, importing a head will be as expensive as a new one
Hmm, so the valves and seals shouldn't be reused?
Aah I see!
I wasn't paying much attention to it, but I did try the fingernail when I first removed the cam, and I think it felt pretty much smooth.
As a general rule of thumb, exhaust valves usually don't cause a lot of problems in these bikes, its almost always the intakes. If it were me, unless the intakes were brand new, I'd go ahead and replace them, the springs and seals.
Joni, you figured out my reference to silicone. I have found it in passages on engines from your size up to diesels and even pumped transmissions. I think in your case and considering where you are I would try a machine shop and see if that one can be saved by someone making you a bearing. It was a common procedure on xr engines to have the bearing surface machined and sometimes even replaced by a needle bearing that was used with the modified cam. that way the came was saved too as the journal got sized down. I see a lot more ingenuity that way coming from your side of the pond than ours right now, for those high taxes you mentioned. the machining on that one does not look out of the question at all.
Well I might just go ahead and replace them then, so I'll know the top end is fine.
Yeah doesn't sound unlikely. Although where are silicone used on these engines except valve cover gasket? There where none to be found on the VC gasket, although this one might not be the first one.
I'll see if I can find any machine shop then, that sounds like a good plan! I've never been in need of a proper machine shop so I've got no idea of where to find one, but Google should help in this case.
Thank you for the information lads (and gals?)!
But how many years are the "first few years"?
Clutch cover.. hmm yeah, good suggestion.
Another question as well, is it a bad idea to turn the crank by hand later on with the cams and chain off, to see if oil flows properly in all the channels? Or does it need a particular speed to even pump the oil?
But how many years are the "first few years"?
Clutch cover.. hmm yeah, good suggestion.
Another question as well, is it a bad idea to turn the crank by hand later on with the cams and chain off, to see if oil flows properly in all the channels? Or does it need a particular speed to even pump the oil?
you look like you have had oil flow issues. i would be looking at the pump or the intake strainer for a problem. had same issue on a yz450f and one cog in the rotary pump had collapsed so it wasnt getting full oil pressure resulting in similar to this. for parts try partzilla.com. just dont get on nne order over $1000 or you will pay gst and import duty at customs 