View Full Version : Gas/ oil premix ratio?

04-26-2002, 08:11 PM
Wondering what ratios members are using? Dino or synthetic? Octane rating?
I've been running 87 octane with an ounce of synthetic 2 cycle racing oil per gallon of gas. No problems I know of, hav'nt had a chance to kill the motor at speed and read the plugs,but have found light oil residue on the plugs after low speed paddock ,garage running. I'm wondering if the ratio I'm using is oil rich?Comments?
Brian B

Mike Cox
04-26-2002, 08:52 PM
Brian, I run 93 octane Amoco with non-synthetic 2 cycle oil with a ratio of 3 oz. oil to 5 gallons of fuel. Discussed with the Hondo motorcycle tech people about synthetic oil and they don't recommend it because of the carbon build up they see on their 2 cylce racing enigines. I get a little smoke when we first crank up but as the exhaust temp rises, the smoke goes away and we have a good clean burn on the plugs. In fact I change the plugs every year whether we need to or not (lol). Hope this helps you out.

04-26-2002, 10:27 PM
When I ran RX-7, It was Ioz with every gallon of the cheapest gas I could find. I used 2 cycle injection oil though. Car ran great

04-27-2002, 08:51 AM
i asked a lot of people what they were doing when i started ended up with mobil one in the crankcase oil injection plugged 50:1 pennzoil 2 cycle (4 oz in 6 gallons)87 octane. make sure your 2 cycle oil is for water cooled engines ( no chainsaw oil )

Festus E. Simkins
04-29-2002, 02:53 PM
I guess everyone uses something a little different. I use Yamalub "R" 1oz to the gal of 87 octane. I have been using dino oil in crank case. My oil injection still operates.

Although I will never protest it. Where does it say you can disconnect or make inoperable the oil injection system on a rotary engine? If anyone knows please post.

The reason I don't use synthetics is because the oil injection system works. However, with the renewed talk I my go to synthetics. I change oil every other weekend so I don't think I really need to go to synthetics.

Any opinions?

Drive well.

04-29-2002, 03:16 PM
This reminds me of the "door glass" thread. The oil injection system cannot be removed, but who is going to inspect that fact that it works properly, or works at all. If you knowingly make it inoperable, then are you cheating? Is there a performance gain? If you can use premix, is there still a reason for the stock injection system to function? Is there drawback to too much oil injection?

Corey L. Clough
EX-1Gen, PRE-2Gen
[email protected]

Speed Raycer
04-29-2002, 06:14 PM
<font face=\"Verdana, Arial\" size=\"2\">Is there drawback to too much oil injection?</font>

One drawback is smoke and getting meatballed!

We weren't sure that the oil injectors worked on our JY motor and did the premix thing. About 4 or 5 laps into our first time on the track, the injector must have started working because we started getting a bunch of smoke. As we diluted the premix with reg. gas, it started to clear up.

Does it say anywhere that we can use premix? (the ole "if it doesn't say you can, you cant" rule)

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04-29-2002, 06:33 PM
I believe I read that 2-stroke oil will make it fail the new fuel test. Any ideas as I would like to help ensure engine longevity by adding a little (100:1 w/OMP attached and working properly)???

Dino, cheap gas.

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04-29-2002, 10:27 PM
2002 GCR, section 17.4.1, Permitted Fuel-Fuel Standards: Classes-All rotory engines-Type-Gasoline w/oil mixture.

Still haven't seen where you may disable or remove the OMP.

Speed Raycer
04-29-2002, 11:12 PM
Thats pretty funny! They'll allow the use of a premix, don't allow disabling the metering pump, and meatball you for smoking http://Forums.ImprovedTouring.com/it/biggrin.gif

04-30-2002, 01:07 AM
Does a cloud the size of long island constitute "smoking"?
in my case it did...

05-14-2002, 12:40 AM
I'm in a class in Canada, different rules, but still no mention of disabling the OMP.

So....just to be sure, is it cool to add some oil to the gas anyway? Is there a combustion or HP question here, aside from the blue haze. I'm not sure how well my OMP works, and I like the idea of lots of lubrication, specially at 8500 rpm, which we do with our streetports.

Karl Bocchieri
05-14-2002, 07:41 PM
It has to be there, but it dosen't have to work.
Rotary engines are alowed to use oil premix, and because of that is not required to pass all parts of the fuel test.
It was all in the Supplement in fastrack.

05-16-2002, 08:17 PM
Does adding oil to the fuel have any fuel filter consequences?

05-17-2002, 04:58 AM
Not on my car. I changed the filters, pre-pump and after-pump (1st Gen) every 4 race weekends(most race weekends were doubles). I never saw anything come out of the filters. I always blew thru them in reverse to check for junk. Does this help?

Corey L. Clough
ITS RX7 Soon-To-Be
[email protected]

Allen Brown
05-17-2002, 10:48 AM
Brooke, I haven't experienced any problems either. I run a syn oil in the pan and a syn 2 cycle oil from Royal Purple or Amsoil in the fuel. Mopac in Calgary carries the Royal Purple, Guyon carries the Amsoil.


05-17-2002, 07:06 PM
It seems as though a premix ratio of 3to5 ounces of 2 cycle oil per gallon is the consensus so far. Is anyone seeing oil fauled plugs?Misfires?
Brian B

05-17-2002, 10:22 PM
Not sure about the 3-5oz/gal concensus.

I would say 1 to 1 1/2oz per gal is more popular. Too little is bad...don't know how much is too much before power goes down.

What is the fuel consumption at WOT? What is the max output of the stock metering pump? What does that ratio work out to?

05-18-2002, 12:04 AM
Anybody else using the 1-1/2 ounces to a gallon ratio?

05-22-2002, 11:50 PM
I run 1 oz/gal of Redline racing 2-stroke oil in 91 ocatane fuel. My OMP works, I just believe in added security! No smoke problem. I've got another competitor who runs 12oz/ 5 gal and no oil metering pump. Again, no smoke. I just took apart a two season old motor--only minor carbon buildup that came right off in the parts cleaner.
I used to share a house with a couple of M/C racers, and after trying Castrol (castor oil), NEO, Redline, and a few others I can't remember the name of, they settled on the Redline because it left the least deposits.


05-23-2002, 12:41 AM
The people at REDLINE recommended thier two stroke racing oil as an excellent,clean burning premix oil for rotaries. They also recommended 30 wt racing oil(without the OMP) with a change every 4-5 events.I don't believe there is a better choice!
Brian B

05-29-2002, 09:26 PM
We always run the cheapest pump gas we can find along with 4oz of BelRay MC-1 oil (Yamalube will do fine too) per 5 gallons of fuel... and we still have the stock injection system hooked up.