i use premix, is synthec oil ok to use? I have no omp, so i beliave its ok to use synthetic oil as ur engine oil(not premix)?

 

YES.


-Ted

 

Synthetic in the cranklcase. Yes.
Synthetic 2-stroke for premix. Yes.

 

So Mobile 1 in crankcase
Whats the name of the best sythetic premix and how much do you use

 

https://www.rx7club.com/rotary-car-performance-77/omp-block-off-plate-557208/

 

Synthetic oil was ok to use before you eliminated the omp too,..

 

Anything really. Redline, Amsoil. I saw Downing using Yamalube S earlier this year in the 792. It's easily available at most cycle shops.

 

I was talking to one of my biker buddies the other day.. he knows his stuff about 2 stokes and does a lot of engine building.

He posed a very interesting hypothesis.. when using the omp, oil is injected into the engine constantly with rpms. With premix and no omp.. oil is subsequently injected only when the injectors are firing..

So on decel, your engine is pumping free air.. the injectors are zero duty cycle, the engine is spinning.. but where is the oil for lubrication under these conditions? This is the reason they dropped premix with many modern bike engines etc..

 

DOnt get what your trying to say? Are you trying to say that on decel there is no gas going through the injectors/motor hence, no premix? You do know that even at idle the egine is injecting gas/premix into the motor....right? Again I just dont understand what your friend was trying to explain to you.

 

Rx7's fuel cut on decel.

 

^ Exactly.

So if you are relying solely on premix in your tank for lubrication, it stands to reason there is no premix oil being injected during fuel cut. At idle your injectors are operational however usually on decel they are at zero duty cycle.

 

I Dought That, When I Let Off The Gas At 5500 Rpm And Throw 3 Feet Flames, I Must Has Gas Going Even With No Accel.....ive Used Premix For 6 Month With No Problems

 

When U Let Off The Gas U Still Hear Combustion,,,,,so Fuel Is Still Going With Oil, And U Got Lubrication

 

If you are throwing flames on decel, you probably have fuel cut disabled for higher rpms? Not everybody does this. Just because you let off the throttle or cut fuel does not mean the engine will stop making a lot of noise. You will still hear the motor running / pumping free air. An engine is just an (extremely inefficient) air pump.

 

It will only throw flames right when you let off the gas becuase you just closed the throttle plates, cutting the airflow abruptly but it takes awhile for this to reach the sensors thus fuel is still injected leading to an overly rich condition.

The other way to throw flames on decel with the stock computer is to barely put your foot on the throttle, ticking the tps into still injecting fuel.

If you have an aftermarket ECU depending on how it is set up it may not cut fuel on decel leading to extreme flameage.

 

Interesting stuff on the fuel cut, we run Klotz in the race car with a 48IDA.

 

I'm carburated too! Fuel never cuts out completely if engine is running.

 

Yes, I should have stressed my remarks were on the assumption that we were talking about a car with aftermarket EFI. Fuel cut generally only applies to EFI systems.

Must add that I think the seperare tank for the metering oil pump and using 2 stroke is a better solution than premix but you better not let that tank run dry!