Ken Powell wrote:

     I hope that I am not beating this to death, but I would like to add a
     little more info on two stroke oils.  BTW, for you non motorcycle guys
     a dykes ring is 'L' shaped and the piston ring land is on the top of
     the piston.  The top of the ring is exposed directly to the combustion
     process so the lubricant is really challenged due to the heat.

     1.  Pennzoil makes a petroleum based 2-stroke oil designed for air
     cooled engines that sells for ~$1.25 a pint (or is that by the
     quart?).  This is what most of the Rotax ultralight and small aircraft
     guys are using.  Note that the Rotax aircraft engines also use a dykes
     ring.  I hear that it works well with few ring sticking problems.

     2.  I had horrible results with outboard motor oils, caster bean oil,
     and a synthetic called Belray.  Note that many guys swore by Belray,
     but I could stick a dykes ring in only a few hours with this stuff.
     Note that I usually ran a slightly rich mixture to promote cooling and
     engine life.  I was always suspicious that this might have kept temps
     a little on the cool side for this oil.  I do know that very few guys
     using a bike with a dykes ring would run Belray.  I raced these bikes
     (Maico's) for about 10 years so had the opportunity to try many
     different oils.  Once I found Golden Spectro, I stayed with it.  We
     would have to test any of these products because I was active in
     racing bikes from 1971 to 1991.  Belray (and the others) may have been
     reformulated and might work great today.

     3.  Golden Spectro worked wonderfully.  It is readily available and
     sells for ~$4.25 per 12 oz. bottle mail order.  Pretty expensive
     stuff.

     4.  This is just my guess, but I think that the TCW-III oils will work
     in our application.  I will test an oil to Paul's 500 degree oven test
     before I use it though.  Compared to what a dykes ring had to endure, a
     500 degree rotor doesn't seem so hot.  BTW, motorcyles do not run EGT
     gauges, but I would be surprised if the EGT ever went over about 1150
     degrees.  I think any more would melt a hole in the piston.  Remember,
     2-strokes do not have a cooling cycle to let pistons and spark plugs
     cool off (2-stroke vs. 4-stroke).

     5.  I will run Pauls oven test on Spectro and OMC outboard this weekend
     and let everyone know the results.

     Ken Powell

Send your wife away on a vacation for a few days:-)

Paul Lamar
 
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