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RPM's - Crank or Rotors?

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Old 09-05-02, 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.
Old 09-05-02, 09:24 PM
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crankshaft.

the rotors rotate at 1/3rd the speed of the eccentric shaft.
Old 09-07-02, 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
Old 09-07-02, 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
Old 09-08-02, 01:52 AM
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Old 09-08-02, 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??
Old 09-09-02, 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
Old 09-09-02, 10:13 AM
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Thanks, fellas.

djb
Old 09-09-02, 09:03 PM
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ok no I understand, thanks
Old 09-09-02, 09:51 PM
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At 6000 rpms, the rotors are moving at 200rpms
Old 09-10-02, 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
Old 09-10-02, 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
Old 09-10-02, 11:36 AM
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Yeah, 9k RPM eccentric shaft speed means the rotors are only moving at 3k RPM. Not bad!
Old 09-11-02, 02:37 AM
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Originally posted by Project84
At 6000 rpms, the rotors are moving at 200rpms

typo-
Old 10-22-03, 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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