Thread: gas/oil
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Old 04-29-2012, 01:38 PM
KCvale KCvale is online now
Motorized Bicycle Elite Member
Join Date: Feb 2010
Location: Phoenix,AZ
Posts: 3,554
Default Re: gas/oil

Just for reference for everyone...

Looking for help on a problem on a given motor and defining it as just 'My Motor' just isn't enough information.
Motors differ. Be specific please because some are just crap to start with.

The only purpose of oil in your gas is to lube the crankcase as it has no crankcase oil, ther crankcase acts as 'ready mix' chamber the motor crank pushes up into cylinder from the intake from your carb.

The Intake manifold does not go directly to the cylinder like the exhaust goes out, it goes into the crankcase and that forces the gas mix up into the cylinder while it is trying to expel the exhaust on the up-stroke.

Too much oil and there is not enough gas to give a real 'boom' of power.
Too little and your lower end wear out from friction.
Have a leak in the lower end and you'll screw up the mix with too much air to cylinder and toast the top end with heat.

This .gif was for explaing how an Expansion chambered works but a pretty good example of how fuel moves from the carb to the exhaust.

I hope that helps.
KC's Krusiers Builds

Last edited by KCvale; 04-29-2012 at 01:49 PM.