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aftermarket cam questions

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I recently acquired an 06 CRF250r. It got several mods already done to it including revalved/resprung suspension for my weight. I'm 6'2", and 190lbs. I feel like I could use a bit more power than what the 250 puts out stock, but don't want to overdo it. Will an aggressive cam like a stage 2 or 3 Hotcam make the bike harder to start? I know a lot of you with a 08/09 cam has issues starting. How would a 14:1 piston and Stage 3 cam do? I do some faster woods riding along with track riding. My bike has an 09 head w/ new OEM valves.

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im certain the 14:1 and Stg2 cam would be a welcome upgrade for your riding....

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I pulled my valve cover last night to see what is in it. Not sure exactly. THe lobes and shaft are black, with the cam gear a raw-like metal color. On the bottom of the right intake lobe is: WW=HCFC No:39. Does anyone know what came this is?

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Just got off the phone with HotCams and they verified it is a Stage 2.

On a side note, those guys aren't very eager to answer questions, and make you feel like you are bothering them.

Since I know what cam is in it, what's the easiest way to tell if the valve springs are stock or stiffer aftermarket?

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most aftermarket springs have a diferent type retainer also cv products springs will fit stock retainers there springs would have a paint stripe on the bottom of the spring pack.from looking @ your pictures i think you probally have stock springs

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That's kinda what I was thinking too. Doesn't make any sense for the guy to put stiffer springs in for a cam that doesn't require them.

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That's kinda what I was thinking too. Doesn't make any sense for the guy to put stiffer springs in for a cam that doesn't require them.

The number one thing I do for a pro rider is to fit stiffer valve springs, even with a stock cam. Valve life doubles. This will work for all riders actually.

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i thought stiffer springs would where the valves faster since they put more presure on the seats?

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i thought stiffer springs would where the valves faster since they put more pressure on the seats?

Stock springs contribute to valve recession due their lack of valve control at high RPM. The valve will actually double bounce off it's seat do to a lack of spring pressure/control.

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Stock springs contribute to valve recession due their lack of valve control at high RPM. The valve will actually double bounce off it's seat do to a lack of spring pressure/control.

i understand that but if the valve is controlled buy the stock spring and the stiffer is not needed then i think the stiffer spring would be putting un nessersary presure on the valves.

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Are there different spring rates when it come to the aftermarket ones?

im sure there are,i would call a few co. and see. with hot cams stage 2 any of them sould be fine.

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The springs job is to hold the valve on the seat and hold the valve actuator to the cam lobe if the spring is doinging its jobe and the cam profile matches the spring the closing ramp is setting the valve on the seat gently the spring is only holding it there.Spring pressur does create friction and can reduce hp the best solution is to lighten the entire valkve train it takes way more pressure to control components than you would thing but a 3 gram reduction is huge.

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