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Service-Information & –
BMWM OTORRAGDM BH Motorcycles R80-R100RS Munich, Jan. 7E
Service Technic
R-V-K-10 vdw/mi 11ยท005 78(1040R
For U.S. and Canada only
Subject: Maintenance of the Exhaust Emission Control System
Ladies and Gentleme11,
The motorcycles manufactured by BMW after 1/1/78 are subject
to the regulations issued by the United States Environmental
Protection Agency.
Among other measures to be complied with by our company the
BMW dealer network will have to perform some new important
tasks. In the following we have listed the most important
items.
Above mentioned regulations should help to moderate the
nation’s air pollution dilemma. We urge you to keep this
intent in mind as you sell and service motorcycles and
related equipment.
In this context two pollutants must be mentioned:
Hydrocarbons (HC) which come from the internal combustion
process, the exhaust system (unburned fuel), crankcase.
Carbon monoxide (CO) which is emitted from internal combustion
engines due to incomplete combustion (lack of sufficient
oxygen).
The emission values for our motorcycles 1978/79 emount to
14 g/km HC and 17 g /km CO. In order to guarantee that these
values are observed, the CO output at idle speed and operating
temperature must amount to 2 % ยฑ 0,5 % CO. This specification
appears on a durable label on the rear fender under the seat
(Vehicle Emission Control Information). Decisive loss of performance
or other negative consequences influencing the performance
must not be expected. Please follow exactly the prescribed
servicing schedule during del ,_very inspection, the
600 miles inspection as well as all other servicing in regular
intervals.
Kenntnis genommen โข Pris connaissance – Noted – Tornado nota – Presa conoscenza
Betr’1ebs!eitung
Direction
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-2-
: Ablage – Archives – File – Arch1vo
Werkstar:
– 2 –
The Clean Air Act prohibits a manufacturer from specifying
that a customer must take his motorcycle only to an authorized
dealer for emission related service. The Act directs EPA to
adopt a parts certification program within 2 years. The Act
further stipulates that emission related services may be
performed by any service facility of the owner’s choosing,
using parts which have been certified under those regulations.
But in order to avoid eventual legal or technical difficultiesto
the customers,it makes good sense to advise them to have
the maintenance performed by competent mechanics.
Referring to warranty there exists an additional item that
all emission related devices on our motorcycles are covered
by 5 years or 30.000 km,*)which ever occurs first. Details
regarding this new warranty policy will be forthcoming
shortly.
The Federal law covering motor vehicle pollution prohibits:
“Sec. 203(a) (3) (A) for any person to remove or render
inoperative any device or element of design installed on
or in a motor vehicle or motor vehicle engine in compliance
with regulations under this title prior to its sale and
delivery to the ultimate purchaser, or for any manufacturer
or dealer knowingly to remove or render inoperative any such (.
device or element of design after such sale and delivery .
to the ultimate purchaser”.
The phrase “remo1Ve or render inoperative any device or
element of design” is commonly called “tamperingi’! and has
been generally interpreted as follows:
A. Tampering does not include the temporary removal or
rendering inoperative of devices or elements of design
in order to perform maintenance.
B. Tampering does include:
I. Maladjustment of vehicle components such that the
emission standards are exceeded.
II. Use of rep 1 ace men t parts or
accessories which adversely affect emissions
performance/durability.
III. Addition of components or accessories that
result in the vehicle exceeding the standards.
IV. Permanently removing, disconnecting, or rendering
inoperative any component or element of design of
the emission control sys~ams.
*) 18.600 miles
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All maintenance information necessary to insure proper
functioning of the emission control system must be
available to anyone who wants one without discrimination
or prejudice.
Following we indicate the required operations to adjust
the exhaust emission system, which are up-to-date. Please
note the detail modifications being already in series
production:
Ad.justing points gap
Take off engine cover. Turn engine with spark plugs removed,
clockwise (facing against direction of travel)
with the aid of Allen head bolt used to secure rotor.
Contact breaker arm (hammer) must lift fully.
Check points gap with feeler gauge: 0,35 – 0,40 mm
(0,014 – 0,016 inches). If necessary replace points.
Slacken off locking screw at anvil point, insert screwdriver
between the two pegs and in slot of anvil point.
Adjust points gap by turning screwdr.iver.
Tighten lockscrew.
Recheck gap.
Ignition Timing
Connect test lamp (12 V) or buzzer with one terminal
to capacitor and earth.
Switch on ignition. Turn engine clockwise, as mentioned
above, and watch marks on flywheel.
After mark (F) appeared, continue turning slowly until
central mark (S) on flywheel coincides with sight
aperture marking.
(Centrifugal weights in rest position). Test lamp must
flash at this moment.
Checking Ignition Timing
Connect stroboscope lamp. Start engine and increase
engine speed up to 3500 rpm. White spot “F” must appear
in insr,P.ction hole when light::.ne ;.,i th stroboscope lamp
at flywheel,
To chec ;,_ ignition advance contr-ol curve, turn wheel on
stroboscope lamp until TD~ ~ark appears. The actual
ignition angle (Spec.: 31 – 1ยฐ) can be reaa from the
lamp’s scale.
– 4 –
At increasing engine speed flywheel mark 11S” disappears
upwards (adjustment commences at about 1550 rpm) until
by still further increasing revolutions white spot
( 11F11 = full advance) appears from bottom in inspection
hole and at 2800 ยฑ 200 rpm it moves to housing mark.
To check ignition delay between left and right cylinder
connect stroboscope lamp alternatively to left and right
ignition cable. Deviation must not exceed 2ยฐ (corresponding
to 4 mm (5/32 in) on the flywheel circumference).
Markings on flywheel: notches 3ยฐ above and 30 below
mark (S).
Engine Idle and CO Level Adjusting
Check that the engine is at normal operating temperature
throttle twist grip is completely closed, cable play 4 mm
(0,16 in), choke being in “off” position, choke arm at
carburetors is pressed into its lower end position.
Adjust idle mixture control screw and throttle stop
screw of both carburetors to their basic settings:
Tighten idle mixture control screw completely for this
purpose and then loosen it by 1/2 turn. (
Tighten throttle stop screw until it just touches throttle
lever, then keep on tightening by one more turn,
Use Duo Test unit, BMW No. 130700, to synchronize the
carburetors by alternating between the throttle stop screw
and idle mixture control screw, Correct engine speed can
be adjusted by turning both throttle stop screws uniformly
in clockwise or counterclockwise direction.
In conjunction with this, CO-level has to be adjusted to
2 t 0,5 ยพ at idle speed with the idle mixture control
screw.
For checking the CO-level we urge you to use a CO tester
which operates on the principle of non-dispersive infrared
(NDIR) analyzing, since this is the only method known to
us which produces a sufficiently exact result. Insert its
sensor alternately in the left and right muffler approx.
50 cm (20 in). Spark plugs must not be sooted for CO-level
test. Every adjustment of the throttle stop screw requires
a CO-level readjustment.
-5- lj
005 78 (1040R)
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To adjust accelerator cables, increase engine speed
slightly by turning the throttle twist grip. Use the
above mentioned Duo Test Unit to synchronize cables.
Never let engine run longer than 10 minutes in stationary
state without sufficient cooling.
Very truly yours,
005 78 (1040F
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