Don Terrill’s Speed-Talk

I'm building a high-compression 2-stroke single cylinder engine and I was wondering if it's possible to mix a lubricant with methanol, and if so, what kind?

joenitro wrote: ↑Tue Nov 23, 2021 11:22 pm I'm building a high-compression 2-stroke single cylinder engine and I was wondering if it's possible to mix a lubricant with methanol, and if so, what kind?

For two stroke engines running on methanol, the pre-mixed lubricant best suited is castor bean oil.

If you can find an equivalent to 'Penrite Race 10/10ths Castor' over there that will do the job. This stuff is a blend of Castor bean oil as David has quoted plus synthetic ester additives, anti corrosion and oxidant additives. These help control the lacquering that straight castor deposits.

Castor bean oil, is like perfume to old motor heads.

I attend the 1959 Times Gran Prix (Riverside), with my dad, that time many Euro race cars used it as a top oil, in the gas and I was hooked.

I ran a 400 Maico MX bike, in the early '70's and used Castrol R (20/1), I loved the smell but, it would foul a plug, in about 6 - 8 gallons.

There's a number of different lubricants that works, it depends slightly on what you intend to do with the engine though. You have castor oil, both regular straight, to fortified, and mixed with synthetic oil.
There's also different straight synthetic oils for this.
You could look at Klotz, they have both castor oil, PAG synthetics and mixes of the two. Redline used to have a really great oil, couldn't find it now though.

Maxima 927 is a very good castor bean based 2 stroke oil.

Back in the early '70's, when I was running my dirt bike, one of the MC magazines, ran a oil test, testing the extreme lubricating quality of oil. It was done by pressing a stylist with a radius, on to a plate, to measure drag resistance. Even though, there were some synthetics on the market then, Castrol R, won hands down.

It gave me the motivation to keep using it, even with the spark plug issues.

That smell, ohhhh that smellllllll !!!!

frnkeore wrote: ↑Fri Dec 10, 2021 3:40 am Back in the early '70's, when I was running my dirt bike, one of the MC magazines, ran a oil test, testing the extreme lubricating quality of oil. It was done by pressing a stylist with a radius, on to a plate, to measure drag resistance. Even though, there were some synthetics on the market then, Castrol R, won hands down.

It gave me the motivation to keep using it, even with the spark plug issues.

That smell, ohhhh that smellllllll !!!!

The lubricating property of castor oil is more about keeping things from a failure. Most synthetics (PAG, Esters) for alcohol is better for lubrication but they behave very differently when (over-)heated, they move away from the heat and eventually break down, whereas castor moves toward the heat and starts to change into more complex lubricants that's even better. So the buildup from castor oil that can stick rings etc is a two edged sword, if you run on the ragged edge and take the engine apart frequently it's great, but not otherwise. Some stabilize the oil to create less sticking, but then it lose the high temperature properties as well.
It smells good no matter what though!

Many years ago, we ran a Porsche 4 cam, air cooled engine using castor oil. It was often difficult to
find so we hoarded the stuff.

One day, at Road America, I met a Porsche factory mechanic who had actually built my engine.

I asked him about the benefits of using castor oil since that engine required its use.

He laughed so hard I thought he was having a heart attack.

He said the oil was terrible and all the Porsche techs hated it. But they had to use it since Castrol
had provided the funding without which they could not race.

But the legend of castor bean oil lives on, a leftover from WWI aircraft engines.