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question for those who replaced valves

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i have a question for those of you who have had there valves go bad an needed them replaced, did you need a valve job or not?

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I just replaced my right intake valve. I definately needed it replaced. The seat face on my valve looked like someone tried to pull the valve through the hole with a pair of vise grips or something. The acutal size of the face was a little over half of what the lower tolerance should be.

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thanks for responding. did you need any machining to the cylinder head or was the cylinder head ok?

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I just did my intake valves and did not cut the seats although you should lap the valves and have a look. If the lapping gives a nice shiny consistant ring on the new valve you should be OK. Our valves are stretching prematurely, if you only have 50 hours on the head you are probably fine. But if you have a worn out engine and you're overhauling it you would want to have the seats done. Eric

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You do NOT lap the valves on these bikes. Lapping the valves removes the coating on them, you'll be doing them again real soon. :cry:

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thanks for responding guys. as of right now my valves are ok but i plan on using stainless intake valves when it is time to change them. one other thing, what did you use to compress the valve springs?

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yea lapping the valves is a no no. the coating going away is one of the reasons the valves go bad in the first place. a valve sping compressor is normally needed.

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I had to use a 5/8 deep socket with the valve spring compressor.You could probably use a large c-clamp with the socket.The compressor worked well with my 450's but would not fit between the spark plug tube and head.

This would not work with reassembly,but I will let the machine shop install new springs and ss valves as soon as kw gets us some.CLAY

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this is way off topic but i was just wondering if Honda knows that there is a problem and what they are trying to do to correct it... i doubt with the 05's the valve problem is going to be gone.. well ok is it really a problem i have a 04 CRF250R and have no problem but i do believe that there is a problem... i checked my Valves last weekend and they were right on.. Now here is another quick thing i got the warranty for my bike now if i have to get a valve job done is that going to be covered under it??? well thanx folks

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Yes, Honda is fully aware that there is a problem with the valves, and NO, they won't step up to the plate and do anything about it. The valve issues on the 04 (and probably 05) CRF's have been well documented by Honda, as well as this website. The bike is a major disaster and will most assuredly cost Honda a big part of the 4 stroke market sales in coming years. If Honda would just acknowledge the mistake that they've made, come up with a fix, and take care of all the unreliable, valve eating CRF's that are out here, they may just save their market. At this point, most of the folks that I know are either switching or at least contemplating a switch to a different color bike. Honda has really screwed the Motocross public with this valve eating monster.

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At this point, most of the folks that I know are either switching or at least contemplating a switch to a different color bike.

Yep, I'm going Yamaha next time for sure. I think this bike is helping 2-stoke sales as well.

It's interesting that some people have problems and others no problem at all. Is it a QC issue? Materials? Design? I just don't get it :cry:

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thanks for responding guys. as of right now my valves are ok but i plan on using stainless intake valves when it is time to change them. one other thing, what did you use to compress the valve springs?

Motion Pro makes a neat little tool for compressing the spring and installing the keepers at the same time, I love mine :cry:

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Jeeeze......I used a short length of 1/2" pvc (won't mar the lifter bore), with windows cut into it, and a "C" clamp. My genuine spring/retainer tool was too big!

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not sure if u have ventured over to the kxf forum, but guys over there are having problems too. Its always the left intake valve. Many reason are to blame supposely... micro dust entering after the filter via the top of the carb, lack of coolant flow to that side of the head, springs, valves themselves, seats, and over reving. :cry: HOpefully in a few years they will have it fixed like yamaha has.

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I wish alot of the guys would go to Yamaha, go there by the bike and trash it on a regular basis on the Yamaha forums. I am sure they would love to have you! Lets see I cut the pink wire to change timing, richened the bike up, cut the air box, modified the filter, added exhaust system, running car oil and I just cant understand why my valves are going bad faster than normal? :cry:

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Motion Pro makes a neat little tool for compressing the spring and installing the keepers at the same time, I love mine :cry:

Is this the tool: Spring compressor

It's $150

No it's this one here

Scroll down to the "Multi Valve tool" :cry: I should also tell you it is for installing the springs and keepers. I use a rubber hammer and a socket to remove the keepers by setting a socket on the retainer and giving it a quick smack with the hammer. Be careful to block up the head so the valves don't hit your bench when you hit the socket or you'll bend them. Hope that helps!!

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