Premixed (Oil In Fuel) Systems - Honda Motorcycle Service Manual

LUBRICATION
PREMIXED (OIL IN FUEL) SYSTEMS:
Premixing engine oil with gasoline is the most widely used system on competition models
The combined airlfuelloil mixture is introduced directly through the inlet tract with the assistance of the carburetor. Lubrica-
tion to the crankshaft and both connecting rod bearings as well as the piston rings and cylinder walls is achieved as this mix-
ture is drawn into the crankcase by the suction of the piston movement.
It is important to USE ONLY THE RECOMMENDED FUELIOIL RATIO. All Honda engines are designed to operate most efficiently
and with greatest durability using the recommended premix ratio. All standard carburetor jetting is based on this ratio.
Standard jetting is based on the recommended premix ratio at sea level and 2 0
'C
( 6 8 F )
CAUTION
Use of afuelloil premix ratio other than the recommended m a y affect overall jetting, engine performance and m a y
lead to premature engine wear or damage.
Freshness of the fuelloil mixture is very important to both the overall performance of the machine as well as the lubricating ef-
ficiency of the oil.
Only use gasoline that has been pumped from a high-volume station within the previous t w o weeks if optimal competition
performance is required. Even general use applications call for gasoline that is no more than eight weeks old.
For optimal lubrication efficiency in this system, use the premixed fuelloil within 24 hours after
it
is mixed. Two-stroke premix
oil that is not stored in resealable containers should be discarded in a proper manner if it is not used completely within one
month after opening. Oil stored in non sealed container is subject to oxidation that degrades the oil's lubrication qualities.
Vegetable-type premix oils separate from gasoline more easily than mineral oils, especially in cold weather. It is advisable to
use mineral oil when ambient temperatures below O°C (32OF) are expected.
CAUTION
.
Mixing vegetable and mineral-based oils will cause premature engine wear or damage.
Date of Issue : March, 1995
4-6
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HONDA MOTOR CO.,LTD.