[Deanzo]

Talking about the motorcycle industry in New Zealand

My friend that has a 2011 250X

His valves would zero after a short ride (or close to it).

He didn't want to go down the road I went (silly him imo)

And has had the work done here,

They have (or at least said) done a head recon, new seats cut and a full Psychic stainless set installed with all the bits and bobs new.

I gave him a hand installing the head with a new gasket and shim it up.

For the intakes, I can only just (I mean just!) get a .005 gap, which is spec with a 1.3 and a 1.35 shim.

That seems like very small shims for new valves, with little room to play if they do move a little.

He paid $750 for the job (that's with us taking the head on and off)

Does that sound right ? (don't worry about the price, it's just the way it is, but letting you know it wasn't done on the cheap)




I went a whole new R head with KW installed and was around 1.9 shim size if I recall, but that may be coz it was a new head... I don't know ?

[JimDirt]

Did the shop replace the seats or just cut them ??

If the seats were replaced the person doing it should be able to figure out how deep to put the new seats to get the shim size up (thicker) , where you have some adjustment back , because the depth of the seat surface determines the size of shim that will be needed to fill the gap(this is all measured while cutting to install the new seats) , if they were just cut , it makes the stem stick up farther just as if the valve face itself was worn , and you therefor get a smaller shim ...make sense ??

You could ask Ken how this process works , but that is the way i understand it , is your seat height/depth determines the starting shim size , and the person doing the work should be taking this into account when cutting the seats so as not to take away too much material , if the seats are cut too deep you can't get that distance back without replacing the seats completely and starting over , again , this needs to be done with that in mind as well , the original thickness of the valve itself and the seat depth make up the total length/distance to the valve stem sticking up , the farther the stem sticks up , the smaller the shim must be , if its close to minimum (1.20) , you can get away with it , but the next time the valves go out , the seat will have to be replaced OR the head replaced with a new one to get a thicker shim to be able to be used

If the seat needed to be cut deep to get the surface smooth , then the customer should have been informed that the tolerances were at the max and to give the customer the choice as to proceed or cut the loss and replace parts as needed , or even get a replacement head and start over fresh , since this will now have to be dealt with the next time the valves need servicing

[crfsonly]

That price is high for the US market. We use the same state of the art CNC valve cutting machine that all deep pocket race teams use. We also use the best stainless valves in the market along with their high performance spring kit. Even with all of this we could not get $750 USD for this work and parts.

As for the shim size, it's not possible to know what shim size the head will require for proper clearance. They will not use the previous shims unless by some complete coincidence. When going through this process we recommend having the Hot Cams Shim Kit so you can have all the shims necessary to correctly clearance the valves.

As for heads we replace valve seats we plan the seat height so that we have less valve stem protrusion than it sounds like you friend's head was left with. I don't know anything about the valves you mentioned were installed. However, if they are a quality stainless steel valve they should be very stable (read won't move much during their usable life) especially compared to titanium valves. So, while I would have provided more clearance space he should be fine if the valves are a quality stainless valve.

Ken

[Deanzo]

I see, thanks.

It "Should" have been new seats, but no easy way for us to know for sure.

Oh, and $750 is NZ$ or around $500US

Psychic cost about half of KW kits, I could find little on line about them.


He doesn't do anywhere near the hours I clock up, so he should be good for some time with that in mind, just doesn't "feel" right to me.

[crfsonly]

For that price and the depth of the seats it sounds like they just cut the current seats. If this is the first valve job and the just cut the seats they likely did so with a form tool by hand or with a mill. He should be fine for awhile if the valves are a quality stainless and the seats were correctly cut.