What 2 stroke oil do you use

I use TTS in the NSR, However the price is getting a bit far fetched used to be $70 for 4L

 

Motul all day.

 

I've tried a few different kinds in the dirt bike. TTS seems to work really well

 

I was using motorex. Now tts

 

I've used Castrol products for along time now without any problems but have switched to Fuchs T2 comp fully synthetic.

 

Penrite is an Australian company with excellent quality oils.
They provide oil specification sheets on their web site which allow you to see the high quality of their oils.

My competition dirt and road two strokes are from 1977 to 1992.
So I prefer to use a JASO FC semi-synthetic oil because they have less detergents than the JASO FD fully synthetic oils.

I use Penrite MC 2ST Semi-Synthetic at 24:1.
This is more oil than is required for lubrication of my bikes even the TZ350F GP race bike.
But 2 stroke oil has other jobs to do other than just lubrication. Ring sealing and heat transfer affect engine power.
I know of two tuners each with their own dynos who both independently found that
for 125cc cylinders 24:1 was the ratio to use with this Penrite oil which gave the most power.
For cylinders larger than 125cc less oil is needed for lubrication and for bikes not ridden so hard less oil is needed for lubrication.

For my nephew's Aprilia RS125 we use the Penrite fully synthetic because the manufacturer recommends using a JASO FD oil.
The detergents in the JASO FD oils assist in keeping the power valves clean.
This is useful for street bikes that may not have their carburetor tuned as accurately as race bikes.

 

Thats about right, 40:1
I had it carefully explained to me once & I cant recall well enough to publish it but only ever use fully synthetic in engines with Nikasil bores
The engine builders are the ones to ask about which oils are the best, the guy up the Bay swears by the Castrol ?? (I'll find out when Dad get back in a week or so) There is a good story attached.
The NSR would have nikasil bores, our 150's do, 2001 models.

 

As I said in my post, I use 24:1 because two independent tuners each with their own dynos worked out that 24:1 gave the most power in a 125cc cylinder using the Penrite oil that I use. They also preferred Penrite over the other oils on the market, as do I.
Also, I do not believe in using the least amount of oil that I can. Modern fuels are hard on 2 stroke cranks.
The 125 GP guys found that they got only 1/4 the crank life when they swapped from leaded race fuel to unleaded.
For me as a racer, power and crank life beat other considerations.

In Dr John Dixon's 2005 book 'The High-Performance Two-Stroke Engine' he states that from a lubrication perspective, fully synthetic oils are not necessary if you are only using petrol as your fuel.

For me the main difference that I see between the JASO FC semi-synthetics and the JASO FD fully synthetics is the amount of detergent used. If the most important thing to you is low emission and keeping your powervalves clean then use fully synthetic at high ratios.
But I just want to win races and not have to do rebuilds as often. I build my own engines.

 

I always do 32:1. HRC also reccomended 32:1 for NSRs without the oil pump, but it all falls back to the jetting as well. I use Silkolene but will change to Motul due to the fact I don't think the flash point of the oil is low enough and I get oil spooge on my CR125 (clean burn otherwise). Best way to check (without a dyno is some runs up and down the street (throttle chops!)). IMO tuning for power on 2 strokes can be dangerous. I like to keep reliability.