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2007 kx250f *New* *Need help!*

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Okay thankyou. My valve is too loose. My clearance is .305mm or (.012in) I need it to be like you said .1~.15mm or (.004~.006in). My current shim that I have on that valve is a 2.60mm. Whch is too thin bc the clearance on my valve is too large. Correct? sorry for the confusion.

yes if your clearance is to large you would need a bigger shim to close the gap.

In all reality looks like someone tried to shim the valves and screwed the pooch..

once you get it set up right you are going to want to keep tabs on the valve clearance often.. I'd say after the first hour and 5hrs after that.. Reason being that if they "zeroed" once before they will do it again quickly..

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Okay thankyou. My valve is too loose. My clearance is .305mm or (.012in) I need it to be like you said .1~.15mm or (.004~.006in). My current shim that I have on that valve is a 2.60mm. Whch is too thin bc the clearance on my valve is too large. Correct? sorry for the confusion.
Put the decimals in the correct place and you will see that it works.

2.75=(.305-.15) + 2.6

There are all kinds of things that come to mind rite now... but I will leave it alone. We are here to help.

Well, I think I need some reading glasses that and I automatically assumed "which 90+% of the time is the norm that valve clearances are less then the spec called for.. so when you said .305 I was assuming that was the shim size "3.05" not the clearance.. Maybe I should have read it a little better before I opened my mouth.. hahaha

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yes if your clearance is to large you would need a bigger shim to close the gap.

In all reality looks like someone tried to shim the valves and screwed the pooch..

once you get it set up right you are going to want to keep tabs on the valve clearance often.. I'd say after the first hour and 5hrs after that.. Reason being that if they "zeroed" once before they will do it again quickly..

yeah they deffinatly did because they were way off and that wear on the old shims looked like some grinded them down or filed them down. I did talk to my local mechanic and he said that wasn't uncommon for someone to do but anyway thanks again for all the help and posts!

:bonk:

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yes, I have ground down shims before to get the exact size I need...

Like I said before you should pay close attention to the valves for a while.. I'd say run it for 1 hr and check again.. then check it at the 5hr mark.. if the valves were shimmed once before due to zeroing out I am willing to bet they will zero again in no time at all.. Thing that sucks about TI valves is when the coating wears off they cup real quick.. General rule of thumb is after the first shim[some times second because on new valves they may settle in and need an initial re-shim after maybe 30-60mins of op time and will be fine there for 40+hrs depending on how well you keep dirt and crap out of the intake tract] the valves will not last but a few hours 10 at max..

So to recap keep an eye on them closely and if they zero out quickly you need to replace them.. when you do need to replace them.. the seats need to be cut, and you do not "LAP" valves in these bikes..

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I don´t know exactly how big the risk is, but the manual clearly states that you should not grind the shims yourself. They say it runs the risk of shattering into pieces.

Maybe the heat treating can be compromised, or maybe they just want to sell new shims. Why risk it? It´s not like it´s a task you do every week. More like every other year with the Kawi!

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they are made from stainless and some other extremely hard metal, they will not shatter under the force of a cam, they will not shatter from grinding, from an engineering stand point there is no risk, other than its a four stroke. :bonk:

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Ill take a ground down shim and give it a few good wacks with a hammer. That should put everyone to ease. Its a piece of stainless. I wouldnt think they would shatter. Its just nice to do instead of running to the shop if your out of that one size shim.

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where did the hammer come from? maybe he wants the shim to have the clearance right in the middle of the limits. on my bikes by shear coincidence, I am at one end of the spectrum and never in the middle so grinding a very small amount will be beneficial for me.

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The hammer would be to make sure the shim doesnt shatter from impact. If it wont shatter with a hammer it wont shatter from a cam lobe hitting it through a tappet.

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they are made from stainless and some other extremely hard metal, they will not shatter under the force of a cam, they will not shatter from grinding, from an engineering stand point there is no risk, other than its a four stroke. :bonk:

Dk's reference is not towards the shim.. It's towards the shim causing the bucket to shatter..

the reason that they say not to grind shims is because if you get it un-even it will cause the bucket to flex and thus running the risk of shattering..

When I "grind" my shims I do it on a piece of plate glass that is covered with wet/dry sand paper using the wet method to achieve the thickness I need whilst assuring that the shim is absolutely level!

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No need to grind shims. Just get it close with what is available between the after market and factory options. I like to set mine on the loose side of the spec. If your within .002" that's close enough. Your engine won't care and you will not notice that's it's .001" or .002" loose.

D-K is correct. The only rite way to do it is with a surface grinder. Even using a granite surface plate and pushing the shim around by hand will cause uneven grind. No matter how even you think you are pushing by hand, you are applying pressure more on one point than another. I know it can be done by hand, but it takes extreme patience and perfectly calibrated tools to be perfect, like a surface grinder.

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No need to grind shims. Just get it close with what is available between the after market and factory options. I like to set mine on the loose side of the spec. If your within .002" that's close enough. Your engine won't care and you will not notice that's it's .001" or .002" loose.

D-K is correct. The only rite way to do it is with a surface grinder. Even using a granite surface plate and pushing the shim around by hand will cause uneven grind. No matter how even you think you are pushing by hand, you are applying pressure more on one point than another. I know it can be done by hand, but it takes extreme patience and perfectly calibrated tools to be perfect, like a surface grinder.

See... I agree to disagree as far as the not noticing the diff.. I set my valves on the tight side of the spectrum.. Reason I do this is for two reasons.. It does increase power "ever so slightly" and it reduces chatter which thus reduces wear marginally but none the less it does reduce it..

on another note.. granite is very rarely a perfectly flat surface even with it being polished.. Plate glass how ever is.. the reason for this is when it is made it is in liquid form. it then is pored ontop of another liquid[molten tin] that it floats ontop of. Due to surface tension and physics plate glass will be perfectly level. sorry had to toss in that tid bit info..

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Plate glass how ever is.. the reason for this is when it is made it is in liquid form. it then is pored ontop of another liquid[molten tin] that it floats ontop of. Due to surface tension and physics plate glass will be perfectly level. sorry had to toss in that tid bit info..

If it is poured out on a liquid it is hardly level. It will have the same radius as the earth, which is not flat as a pancake. hehe.:bonk:

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If it is poured out on a liquid it is hardly level. It will have the same radius as the earth, which is not flat as a pancake. hehe.:bonk:[/QUOTe]

hahah sure if it was long enough.. and they built the containment vessel to follow the curvature of the earth

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hahah sure if it was long enough.. and they built the containment vessel to follow the curvature of the earth

It doesn´t have to be long. The radius of the surface in a glass of water is the same as in the pacific ocean.Just very hard to measure. Isn´t it great. My mind boggles.:bonk:

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It doesn´t have to be long. The radius of the surface in a glass of water is the same as in the pacific ocean.Just very hard to measure. Isn´t it great. My mind boggles.:bonk:

What ever DK.. For all intensive purposes that the radius of the glass to the size of the shim would instill a perfect plane and thus be suitable for in my terms polishing enough material from the shim.. How ever as stated before that uneven pressure can result in an abnomality.. how ever in relative tearms the way I do it is safer then someone using a grinder or hand grinding the shim to the size they wish..

Keep in mind that I have only did this twice that I can remember and I had thought about the issue of being ground uneven to the point where it could cause an issue.. thus the use of plate glass..

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