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RPM's - Crank or Rotors?

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Old Sep 5, 2002 | 03:50 PM
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RPM's - Crank or Rotors?

Probably a dumb question, but, are the RPM's registered on the tach the crankshaft or the rotors?

What is the ratio of rotor revolutions to crank revolutions?

Thanks.
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Old Sep 5, 2002 | 09:24 PM
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crankshaft.

the rotors rotate at 1/3rd the speed of the eccentric shaft.
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Old Sep 7, 2002 | 03:14 AM
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the rpm is the crank speed . The crank to rotor gear is three to one . That is controled by the stationary gear and the rotor gear
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Old Sep 7, 2002 | 04:59 AM
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Eccentric, baby! The rotary has no crankshaft. But the info is right -- tach reads main shaft speed, rotors turn at 1/3 the indicated speed.

-Max
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Old Sep 8, 2002 | 01:52 AM
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Old Sep 8, 2002 | 09:23 PM
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what is the tech word for the shaft in the rotary??? So is it 3 shaft revolution is 1 rpm??? or is it 2 shaft revolutions per rpm??
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Old Sep 9, 2002 | 12:12 AM
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1rpm is the e-shaft or the crank turning one complete revolution in one minute. 1000 rpm== the e-shaft turning 1000 revolutions in one minute . in one e shaft revolution the rotor has moved 1/3 of a revolution. Ok
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Old Sep 9, 2002 | 10:13 AM
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Thanks, fellas.

djb
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Old Sep 9, 2002 | 09:03 PM
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ok no I understand, thanks
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Old Sep 9, 2002 | 09:51 PM
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At 6000 rpms, the rotors are moving at 200rpms
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Old Sep 10, 2002 | 12:13 AM
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How do you get 200 rpm for the rotors at 6000 rpm shaft speed. now I am stupid
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Old Sep 10, 2002 | 01:29 AM
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6000 RPM eccentric speed (as shown on the tach) = 2000 RPM rotor speed. The rotors turn at 1/3 the eccentric shaft RPM.

-Max
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Old Sep 10, 2002 | 11:36 AM
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Yeah, 9k RPM eccentric shaft speed means the rotors are only moving at 3k RPM. Not bad!
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Old Sep 11, 2002 | 02:37 AM
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Originally posted by Project84
At 6000 rpms, the rotors are moving at 200rpms

typo-
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Old Oct 22, 2003 | 08:54 AM
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do you guys know if the tach will still read the crank angle sensor with the egi fuse?

im doing a compression test and my readings are 7.5, 7.5, 0.0. the rpm on the gauge show 999. also it does the same thing on both rotors. when i crank the car, the tach dosnt bounce. it acts like its not counting the revolutions. do you know how to check for bad sensors or what the problem might be.
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