Author Topic: megacycle cam question.  (Read 2299 times)

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Offline Sam Green Racing

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megacycle cam question.
« on: February 16, 2011, 04:50:38 AM »
Has anyone tried a 125-90 camshaft, what rpm did it make power at ?

Sam. ;)
C95 sprint bike.
CB95 hybrid race bike
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JMR Racing CB750A street ET drag bike

Offline kos

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Re: megacycle cam question.
« Reply #1 on: February 16, 2011, 06:16:15 AM »
Drag race, 12/1 comp or higher. lots of duration. all top end, high RPM use only.
What you got in mind?

KOS
220...221, whatever it takes.

Offline Doctor_D

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Re: megacycle cam question.
« Reply #2 on: February 16, 2011, 06:26:21 AM »
Unlike high-lift, moderate duration cams that preserve low-end power by retaining decent static compression, long duration, moderate lift cams have less static compression at lower rpm's because of the longer period when the intake valve is open on the compression stroke. To overcome the loss of static compression, one needs to increase the compression ratio.  Long duration, moderate lift cams have valve-control (less violent valve movements) and port velocity (better cylinder filling) advantages over high-lift, moderate duration cams at higher rpms though. In any case, that's the the way I remember the theory being explained.

In the right motor, the 125-90 may be gutless until 6k or so, but it should have long legs -- pulling strong to or past redline. Interested to see if my hunch about where it makes power is right.
Take care,
David
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Offline Sam Green Racing

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Re: megacycle cam question.
« Reply #3 on: February 16, 2011, 06:31:12 AM »
Mark/Dave I know what it does, I just wondered where it did it. ;D ;D how far up the rev band did it push the power.? need to know from someone with experience of this cam. ;)

Sam. ;)
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike

Offline kos

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Re: megacycle cam question.
« Reply #4 on: February 16, 2011, 01:35:42 PM »
Mark/Dave I know what it does, I just wondered where it did it. ;D ;D how far up the rev band did it push the power.? need to know from someone with experience of this cam. ;)

Sam. ;)


Sorry, I have not used this cam in any of my builds or customer engines.

KOS

220...221, whatever it takes.

Offline Sam Green Racing

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Re: megacycle cam question.
« Reply #5 on: February 16, 2011, 02:14:27 PM »
Drag race, 12/1 comp or higher. lots of duration. all top end, high RPM use only.
What you got in mind?

KOS

Next stage for my drag bike Mark, 12/1 1,000cc.

Sam. ;)
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike