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interchangable parts

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My 04 RMZ blew up a week ago. Both exhaust valves came apart destroying the motor from the crank up. I need to know what parts are interchangable between the 04-05 RMZ/KXF. I would like to put in new 05 parts since I hear there were several changes to alleviate some of the valve train problems. Also if anyone knows where I can get a deal on a good cylinder head I would appreciate it.

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are you sure it was the exaust valves, you stated you lost both at the same time, check cam sprocket indexing, might be your failure, the 05 heads are on factory backorder no eta available, as far as head internals they are the same, heads are changed though to increase upper Rpm, longer intake runners. I think you would be the first case I know of to have had an exaust valve failure, espeacialy on two valves.

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How many hrs did you have on the motor, and are you sure both failied? When one fails it takes out everything. We blew on engine already and when we got it apart there really wasn't much left to lok at, just one valve jammed sideways in the seat everything else was gone, couldn't tell what went first.

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I only had about 7 hours on the motor since the top end was replaced. I am sure that it was the exhaust valves and all I can say it they both broke where the stem is fused to the valve head. Now everything looks like my 5 yr old took a dremel to it. Totally useless. I need new internals from the crank up. The bike ran good up until it popped. But what do you do rebuild and move on. So does anyone know if the parts are interchangable? My local dealer said they had totally different part numbers and he didn't have a price on them yet.

parts

head

piston

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I did a top end on my sons 04 in November and I just bought a new head instead of machining the seats on mine and installing new valves. The bike didn't break any valves or anything, I just wanted to change them out before we had any issues.

I still have the 94 head, but it will cost you $150-200 to have it machined after you buy it and you can buy a new one for around $400.

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Where did you buy the head from. I was quoted 572.00 for a new one.

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Here's a place I found on the web I haven't tried them but there prices don't seem out of line I know dealer cost for a head is around 280.00 and there charging 379.00. I checked the prices and for the head and valves, springs all the guts you need your looking at 668.81 this sin't including piston, cylimder etc.

http://www.generationmx.com/mxmall/2004KX250Findex.aspx

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suz459,

I appreciate it. I picked my bike up from the shop today along withthe box of broken parts. My mechanic kept the head because he is going to try and salvage it. I got home and started looking at the parts and guess what I found? I think I may have found the gremlin that made the motor go south. The gear on the cam has moved knocking the timing off and arranging the meeting between Mr. Piston and Mr. Valve. Take a look at the pics and tell me if my suspicion is correct.

intake cam

exhaust cam

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