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Old 09-12-16, 05:18 PM
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OMP question

Why does everyone delete OMP? Does it cause flooding? I understand you can premix.
Old 09-12-16, 05:48 PM
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S4 OMP is mechanical. The S5 OMP is electronically controlled. The electronic one, with age, can short out the unit itself and in the process damage the ECU.
Old 09-12-16, 05:54 PM
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thanks Makes sense now
Old 09-12-16, 06:58 PM
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Originally Posted by satch
S4 OMP is mechanical. The S5 OMP is electronically controlled. The electronic one, with age, can short out the unit itself and in the process damage the ECU.
Not sure this is an issue on FD's. Main reason people delete them (on FD's) is simplification. IMO, you can't have enough lubrication

Good job getting your post count up BTW
Old 09-13-16, 01:40 AM
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Originally Posted by TomU
Not sure this is an issue on FD's. Main reason people delete them (on FD's) is simplification. IMO, you can't have enough lubrication

Good job getting your post count up BTW
I think he has a 1991 RX7.
Old 09-13-16, 10:45 AM
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Originally Posted by zero06
Why does everyone delete OMP? Does it cause flooding? I understand you can premix.
A little cynical but seems like it's like A/C and power steering. If anything goes bad they're too cheap or lazy to fix it. In some cases just pre mixing is as good or better. In some cases...not.
Old 09-16-16, 08:46 PM
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Why do people do both? premix and still have OMP seems like over kill
Old 09-17-16, 07:10 AM
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^---> https://www.rx7club.com/new-member-r...esign-1104813/
Old 09-17-16, 09:04 AM
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anyone with any experience premixing for 2 stroke, whether it be for a dirt bike or weedeater, should know premixing for automotive application is a bad idea. the premix is heavier than the fuel and will settle out, requiring agitation to re-suspend the premix in the fuel with every use. over time this will build up. i have a fuel tank from an 83 that proves this. it is impossible to adequately premix the fuel in the tank of an automobile.
Old 09-17-16, 10:32 AM
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Originally Posted by zero06
Why does everyone delete OMP? Does it cause flooding? I understand you can premix.
Ignorance, mostly.

And then there are the rare cases where the car is sufficiently modified that premix is the best option, or used at the track.

But mostly ignorance.
Old 09-17-16, 11:45 AM
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Originally Posted by rxtasy3
anyone with any experience premixing for 2 stroke, whether it be for a dirt bike or weedeater, should know premixing for automotive application is a bad idea. the premix is heavier than the fuel and will settle out, requiring agitation to re-suspend the premix in the fuel with every use. over time this will build up. i have a fuel tank from an 83 that proves this. it is impossible to adequately premix the fuel in the tank of an automobile.
I have quite a lot of experience with two-stroke... in my weedeater, leaf blower, chainsaws, and along time ago...a lawnboy. I also pre-mix at a reduced rate with the OMP on my car, and disagree. Maybe if the car is parked for a year or two after putting it in after fueling. Otherwise two-stroke is designed to stay in suspension and I've never had any issue in the tank, pump sock, fuel filter or injectors. And doubt I'm the only one. There is a pretty extensive history of people that have been pre-mixing for many years that would offer similar 'proof' that it's not a problem.
Old 09-20-16, 10:34 AM
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Think you'll only get sludge in your tank if you use the wrong oil or a very high oil to gas ratio. You can always pull your hanger periodically to check things out.

FWIW, I use

ZX-2SR | Legend Performance Inc.

Don't have enough miles to confirm or deny the claims tho
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