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Crf450 Steel Valves

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I remember reading a post about some steel intake valves for a crf450. I think it was on TT. If anyone remembers this, please post and let me know.

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I used TRX450 SST Valves for the intakes.

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Kibblewhite (aka Black Diamond) SS valves are the best insurance against breaking a valve head off from too tight of tolourances as with ti valves if they are not REGULARLY checked, the KW valves are best used with there respective valve guides, springs and retainers, ti retainers can be used if you wish to keep the valve train as light as possible, perform the appropriate valve job making sure the face is concentric to the seat, choose the appropriate cam for the application and set up the valve clearences on the loose side, (unless you are engaged in close course competion and need every advantage, then I would set up the intakes tight (for max lift and flow) and exhaust's loose (as not to be so tight that it may hang open and burn a valve) but inspect before every race weekend.

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The Honda valves are good for one weekend of riding, and I'm down to the thinnest shim.

What's up with that??? I have an 03 and my valves have not been re-shimmed yet, and are still in spec!

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I ride or race every weekend, and I rev it to the moon. In the last few months they begin to beat out sooner and sooner. When I put in new intake valves, I'm starting out with almost the thinnest shims in the kit. After one weekend of riding, I have to use the thinnest shims in the kit. Out of desperation to ride, a couple of times I took the intake lifters out and machined off about .010 off of the nipple on the under side, just to gain some clearance. Then after a weekend of riding, there is zero clearance. I considered taking some off the top of the intake valves, but there isn't much meat above the keepers. The intake seats do not appear to be sunken in the head that I can tell. I'm going to try some of the stainless valves and spring kit, and see what happens. I also thought about making the intake seats a little wider to spread the load out on the face of the valves. It may disrupt the flow and loose some power, but I'll just twist the throttle more to gain it back. My intake boot is sand free everytime I clean my filter, but I don't think sand is an issue because I think it would also sand blast the throttle slide and bore. You probably would also see some sort of tracking marks. I change the oil every other ride (royal purple synthetic), but again oil I don't think is an issue for the valve face, valve guide yes. The guides are within specs. The exhaust clearance never changes. If the stainless does not work, I guess I'm just relegated to a life of constant intake valve replacement.

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I'm installing SS valves right now & need to know how to progress after removing the valves. How do you remove the valve seat? Is there somewhere online to look at a service manual? This is my first time replacing the valves and I thought my Honda Owner's manual was a service manual (Wrong). I have been a YZF owner for a long time & am used to getting the service manual with the bike.

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Kibblewhite (aka Black Diamond) SS valves are the best insurance against breaking a valve head off from too tight of tolourances as with ti valves if they are not REGULARLY checked, the KW valves are best used with there respective valve guides, springs and retainers, ti retainers can be used if you wish to keep the valve train as light as possible, perform the appropriate valve job making sure the face is concentric to the seat, choose the appropriate cam for the application and set up the valve clearences on the loose side, (unless you are engaged in close course competion and need every advantage, then I would set up the intakes tight (for max lift and flow) and exhaust's loose (as not to be so tight that it may hang open and burn a valve) but inspect before every race weekend.

you got it backwards the crfs actually gain clearance when hot almost all aluminum heads do. running the valves loose lash just brings the lifter further up the cam @ a more agresive area of the lobe causing the valve to hit the seat faster and causing premature wear or breakage .

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