Valve seat question

I have a 04 CRF250 with some valve problems. I bought this bike new in 04 and was regular with the valve adjustments. I reshimed my valves all the way down to the smallest possible shim, just prior to my last ride of the season knowing that I would have to do valves over the winter. My question is. I bought the stainless steel valves and lapped them in. I went ahead and tried to find the right shim that would get me my clearance. Come to find out im right were I was on my last ride. My exhaust is at the smallest shim. This tells me that valve seats are trash? Right? If I send my head off to have the seats cut removing more material from the seats thus having the valve sit in the head farther, will I be able to get my measurements to come out or am I just putting a Band-Aid on valve seats that should be replaced all together? And if indeed I need to replace the valve seats does anyone know a good shop that will not empty my bank account. I’m not a pro or anything I just need this fixed so I can ride.

After you get your seats cut you will be fine. never install new valves without cutting the seats

I have a 04 CRF250 with some valve problems. I bought this bike new in 04 and was regular with the valve adjustments. I reshimed my valves all the way down to the smallest possible shim, just prior to my last ride of the season knowing that I would have to do valves over the winter. My question is. I bought the stainless steel valves and lapped them in. I went ahead and tried to find the right shim that would get me my clearance. Come to find out im right were I was on my last ride. My exhaust is at the smallest shim. This tells me that valve seats are trash? Right? If I send my head off to have the seats cut removing more material from the seats thus having the valve sit in the head farther, will I be able to get my measurements to come out or am I just putting a Band-Aid on valve seats that should be replaced all together? And if indeed I need to replace the valve seats does anyone know a good shop that will not empty my bank account. I’m not a pro or anything I just need this fixed so I can ride.

Sounds like an unusual situation. Normally the valves are the worn component causing loss of valve lash clearance and the need to use a thinner shim, and usually on the intake side. If the seats in the head are worn badly, or have been cut a time or two already then replace the cyl head and install new valves.

There are several sources on this board that people use to get valve work done, RHC is top notch, mx time, Agent smith to name a few.

I bought this bike new in 04 and was regular with the valve adjustments.
As soon as you start having to make "regular" valve adjustments, it's time to replace parts. Continuing to adjust with smaller shims is asking for major trouble.
I reshimed my valves all the way down to the smallest possible shim, just prior to my last ride of the season knowing that I would have to do valves over the winter.
If you went through the entire range of available shims, it's probable that both the seats and guides are toast.
I bought the stainless steel valves and lapped them in.
Lapping in new valves to destroyed seats certainly isn't good for the valves. Lapping is a finishing operation and should only be done with new or remachined seats.
I went ahead and tried to find the right shim that would get me my clearance. Come to find out im right were I was on my last ride. My exhaust is at the smallest shim. This tells me that valve seats are trash? Right?
Probably.
If I send my head off to have the seats cut removing more material from the seats thus having the valve sit in the head farther, will I be able to get my measurements to come out or am I just putting a Band-Aid on valve seats that should be replaced all together?
Depends on whether the problem is with the new valves or the seats. If you've removed too much material from the new valves during lapping, new valves and machined seats may fix the problem. If the seats have receded too far already, machining them will only compound your problem.
And if indeed I need to replace the valve seats does anyone know a good shop that will not empty my bank account. I’m not a pro or anything I just need this fixed so I can ride.
Having your head fixed up by a reputable shop might be possible for less than the cost of a new head, but a new head comes with improved port layouts and could add some power. I'd go with a new head, springs, valves and seals. Even if you go with a new head, I'd suggest you send it to a reputable shop to touch up the seats and make sure everything is perfect.

Thanks for all the help. Looks like I'm going to have to throw more money at it. Kinda sucks all I wanted was one more year outa the old lady before I traded her up.

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