Breaking the motor in.
Machines should be run at speeds running
from 35 to 55 miles per hour for not less than 200 miles. This "break in"
running is for the purpose of obtaining a high polish on the cylinder walls
and a positive seal on the piston rings, as well as as to allow all bearing
surfaces to "wear in". More miles of "breaking in" may be necessary
if the motor does not feel like it is ready to go.
Never use heavier than SAE #30 for "breaking
in" purposes.
Never open the motor up until the oil
in the tank is WARM.
Reheat the oil if neccesary, before pouring
in the tank.
Use #50 INDIAN OIL after the engine is
broken in and change often.
Never allow the motor to labor or over
peak in high gear.
Consult instructions on gearing and ignition.
Ignition.
The spark advance setting is 11/16" for
the 648 model; spark plugs fire when the pistons are 11/16" before top
dead center on the compression stroke.
To set the spark timing accurately it
is neccessary to remove the rear cylinder head. Magneto point setting
is .015 exactly.
Use Champoin JA-11 or LA-14 spark plugs.
Clearance Chart and Specifications.
Intake Valve Clearance |
.010 motor cold. |
Exhaust Valve Clearance |
.010 motor cold. |
Valve seats |
35 degrees |
Piston clearance |
.0075 minimum |
Ring gap |
.018 minimun |
Connecting rod lower bearings |
.0025" -.003" |
Connecting rod upper bushing |
.003" |
Flywheel end play |
.010" - .015" |
Drive shaft bearings |
.0015" minimum |
Spark Advance |
11/16" |
Magneto point setting |
.015" |
Compresion ratio |
6 to 1 |
Cams |
Bonneville type |
Pistons |
High top - 2 compresion rings and oil
ring |
Gas tank capacity |
4 1/2 gallons |
Oil tank capacity |
1 1/2 gallon |
Gearing.
Indian riders are encouraged to keep records
of all meets and events, indicating conditions of course, type of event,
speeds obtained, gear ratios used, and weather. Such records will be helpful
in the following year or similiar events. Experience is the best teacher.
The attached chart shows gear ratios for
the varios sprocket combinations available on Model 648's (not attached
here, but this should be pretty easy to figure out on your own). If
a rider expects to compete in all types of class "C" events he should have
the range of sprockets shown:
13, 14, 15, 16, 17, 18, 19 and 20 tooth
counter shaft sprockets
36, 39, 40, 41, 42 and 43 tooth rear wheel
sprockets.
The 18 and 40 tooth sprockes are assembled
on the machines.
THIS GEARING MUST BE CHANGED BEFORE ATTEMPTING
TO MAXIMUM TOP SPEED
The suggested gear ratios for the Daytona
race are:
20-39 4.21
20-40 4.32
20-41 4.43
One mile speedways, such as Langhorne:
19-41 4.66
Time trial:
18-40 4.80
1/2 mile dirt tracks:
15-42 6.06
15-43 6.21 most popular |
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These instructions might
come in handy when Jim's and Lyle's 648 engine cases are done... :-)
Expect an update on this
project next month. Meanwhile a click on the picture below will take you
to the story so far.
Big Base 648 cases.
648
More racing stuff
from Jim here!
Use your browser's "back"
button
to get back here.
Intro to Sport Scout Racers.
All about factory racing
tanks.
How to strengthen your rear
frame for racing.
How to narrow your forks.
648
All about Indian cams -including
the experimental "4-cams",
which
you will hear more about
soon...
648 |