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Over-rev

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Old 07-31-2007 | 12:02 AM
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Over-rev

What happens to rotary that is over-reved? (As in a messed up down shift.) I know with a piston engine, if you over-rev, you can drop a valve, or spin a bearing, or bend a rod, etc. In a rotary, does the main shaft bend? That's the only thing I can think can happen and even that should take a lot of revs to bend with as thick as it is.

P.S. I'm talking internal. I know the accesories will usually give out before the motor.
Old 07-31-2007 | 12:18 AM
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do it & tell us what happens .....
Old 07-31-2007 | 12:57 AM
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carbon shoots out so fast, it could kill a man.
Old 07-31-2007 | 03:53 AM
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Originally Posted by CohdeyTakahashi
carbon shoots out so fast, it could kill a man.





LOL!
Old 07-31-2007 | 03:56 AM
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a piece of the flywheel takes off your foot faster than you can say "oh sh-t" on a six flags amusement park ride
Old 07-31-2007 | 04:21 AM
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take this with the weight of a grain of salt....

it seems i read somewhere that our motors are balanced to spin up to something like 13,500rpms. anything more than that and vibration wil practically disentigrate the motor. now i've accidentally shifted to 2nd gear twice while redlining 3rd... both times: my dash lit up like a Xmas tree; ABS/TCS/DSC or something went apeshit trying to keep the rear end straight; and the tach jumped to what i guestimate would be around 11,000-11,500rpms.

scared the living shyte outta me both time, but i havent seen any negative effects yet. i dont know much about rotories, but i expected an early symptom would have been chatter from the seals(apex?) luckily *** seems well for the last 5-10K miles since.
Old 07-31-2007 | 04:13 PM
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Originally Posted by TeamRX8
a piece of the flywheel takes off your foot faster than you can say "oh sh-t" on a six flags amusement park ride

Big Daddy? How many of you can rember this? I lived right across Lions.
Old 07-31-2007 | 05:00 PM
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I remember this being discussed a long way back. I also recall the 13K figure being thrown about but I wouldn't bet my engine on it. The things that start to go wrong, iirc, do include flex of the eccentric shaft. And if that flexes, then the rotors are no longer rotating in-plane, and start tearing up the side and apex seals, end plates, housing... yada yada
Old 07-31-2007 | 05:04 PM
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From: Misinformation Director - Evolv Chicago
Originally Posted by TeamRX8
a piece of the flywheel takes off your foot faster than you can say "oh sh-t" on a six flags amusement park ride
Mmmm...ballistic blanket...
Old 07-31-2007 | 06:21 PM
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On my first track day last October at Road America I over revved the engine at least 5 times. When I say over rev I mean I downshifted to 2nd before I slowed down enough. The engine cut off fuel all 5 times. It was my first time on a course. Since then I have done 6 track days with no issues. Just don't make a habit out of it.
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