Try a shop that sells/services off-road motorcylces, ATVs, or snowmobiles.

 

^
what he said. I picked up some yesterday from a local Yamaha dealership.

 

sadly i purchased royal purple 2 cyl to premix before reading this thread. what it sounds like is that the reason not to use is because it'll clog the cat. thing is, I have a black halo racing catless midpipe on my 8 so I was wondering (I'm going to buy idumetsiu after I post this) but could i get away with using the two bottles of rp for the time being?

 

Royal Purple HP is pretty good for a marine oil, I'd use it up as a 50/50 mix with a better lube....

 

Any good JASO FC or FD rated 2-cycle oil is fine. Lucas SemiSyn 2-Stroke (FC matches but not officially rated; Amazon has best price of $30/gallon) or Mystic JT4 (FD rated).

 

I run Motul 710 2T

JASO FD

 

I use the redline synthetic race 2 stroke and mix at 2 oz/gallon. Lower octane will slightly improve power and the extra lubrication doesn't hurt.

 

This is an ancient fallacy, common in the interwebs - octane is in NO WAY related to the 'power' in a gasoline.

I have made gasoline for a major oil company, for over 30 years - I could make you a tank of 150 'octane' fuel, or a batch of 75.....and either could have more 'power' depending on my blend.

 

I'm not saying there is more power or less power in any octane gasoline but the rotary combustion chamber geometry and rotor speed seems to respond positively to lower octane fuel. I have not personally tested this on a dyno in a scientific way but others have over the years.

 

We've heard it all before, numerous times. Usually by people who don't really know what they're talking about.

 

Is there anyone out there with data on this subject?

 

clearly not you

The spec fuel for the Formula Pro Maxda with Renesis 6-port was 95 octane with premix from VP, not sure what it is now, but I doubt there was premixing just to get octane lower and that's why they removed the OMP as part of their mad skills to get more power

 

The US Army...
https://www.arl.army.mil/www/default...al_report=6149

Happy reading

 

A paper speculating on how to spend a multi-trillion dollar military budget researching ideas

 

Around page 15 it gets into engineering.

 

A hyped up, theoretical-based paper aimed at winning a financial contract and eventual reality are not the same thing. Never mind that its not gasoline or ethanol based, is fixed rpm, and the the design concepts otherwise being discussed there are not relevant to either the Renesis or 13B automotive engines. If you go to the summary the coulda-shoulda-woulda is very apparent. I suppose you're still filled with enthusiastic zeal after reading the Renesis SAE paper for the umpteeth time despite the reality documented on the forum.

 

I'm not sure we're talking about the same paper. Dod you only read the summary? This one includes transparent engine photography, pressure and flame front data, for multiple combustion chamber shapes. It also goes into some depth about apex seal behavior, with data. The majority of sourced articles are from automotive applications.

If you have some better source that answers the question posed above, please bring it.

 

I read the whole thing. Did you write it, lol. A lot of it is just bits and pieces cut & pasted together from a wide range of sources. I thought it was mostly a bs con job, but that's just my opinion as a mechanical engineer with a critical eye and a very sensitive bs detector. Experience and age have made me a weary cynic ...

plus you didn't even address my points or how any of your own relate to our engines relative to this discussion. The application and operating conditions are substantially different. Please see my comment in Post #35 ...



.

 

Just buy JASO FD rated Lucas 2-Stroke SemiSynthetic premix on Amazon. Any JASO FC or FD rated 2-stroke oil will do.

 

Has anyone used this for premix?

 

It is JASO FD so it is good. Enjoy. I use whatever is cheap and rated JASO FC or FD.

Ed

 

FD rated for my FD woot!