You guys bring up a whole other topic when you mention oil contributing to combustion. It's one that gets debated on the two stroke forums all the time, kind of like mineral vs syn and breakin.
Here's another link (http://www.geistware.com/rcmodeling/articles/oil_test/) from the RC guys on a carbon test they ran. Notice the last oil tested (belray) required 15% more fueling to maintain the same engine temps. A switch to this oil on a machine that was jetted on the edge with another oil could create a lean seizure, even though both were mixed at the same ratio. Doesn't make the belray a bad oil, just shows that at the combustion temps in this test it doesn't contribute much to combustion, where the others do. Something you would want to make adjustment for.
Also note the increase in hard carbon formation and scuffing running the 100:1 oil vs. the same oil at 50:1. So if you think you cuttin a fat hog running 100:1 oil escaping the evils of carbon and smoke, think again.
The longer you hold a twostroke wide open the more fuel it need. Load adds to it also. You could jet it perfect plug color for a 1/4mile drag race and burn it down running a mile. A tuned mx bike is jetted for short bursts at WFO. Take that same bike to the dunes and load it up with a paddle tire and hold it wfo for long pull and squeek it. 14.7:1, LOL. Not for long. 4 stroke gets away with it because it has a wasted stroke that helps cool the piston. A 2 stroke makes heat every stoke and doesn't have that luxury so uses the fuel/air as a cooling media, they need more. On a long pull the piston gets hotter and hotter and hotter, the pipe gets hotter and hotter increasing the scavenge which pulls more air which require more fuel and more fuel and if the machine isn't jetted fat it will reach a point of lean seizure or holeing the piston. Point is, the bike has to be jetted for it's intended use.
Here's another link (http://www.geistware.com/rcmodeling/articles/oil_test/) from the RC guys on a carbon test they ran. Notice the last oil tested (belray) required 15% more fueling to maintain the same engine temps. A switch to this oil on a machine that was jetted on the edge with another oil could create a lean seizure, even though both were mixed at the same ratio. Doesn't make the belray a bad oil, just shows that at the combustion temps in this test it doesn't contribute much to combustion, where the others do. Something you would want to make adjustment for.
Also note the increase in hard carbon formation and scuffing running the 100:1 oil vs. the same oil at 50:1. So if you think you cuttin a fat hog running 100:1 oil escaping the evils of carbon and smoke, think again.
The longer you hold a twostroke wide open the more fuel it need. Load adds to it also. You could jet it perfect plug color for a 1/4mile drag race and burn it down running a mile. A tuned mx bike is jetted for short bursts at WFO. Take that same bike to the dunes and load it up with a paddle tire and hold it wfo for long pull and squeek it. 14.7:1, LOL. Not for long. 4 stroke gets away with it because it has a wasted stroke that helps cool the piston. A 2 stroke makes heat every stoke and doesn't have that luxury so uses the fuel/air as a cooling media, they need more. On a long pull the piston gets hotter and hotter and hotter, the pipe gets hotter and hotter increasing the scavenge which pulls more air which require more fuel and more fuel and if the machine isn't jetted fat it will reach a point of lean seizure or holeing the piston. Point is, the bike has to be jetted for it's intended use.
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