Black Box V5.1 Guía para resolver problemas descargar pdf (Pagina 25)

Euro MotoElectrics, 25958 Genesee Trail Road PMB 321 Golden, Colorado USA 80401 EDL-IGN Page 25 of 43

www.EuroMotoElectrics.com info@euromotoelectrics.com Tel: 1-303-526-0901

EnDuraSpark Electronic Ignition

Installation & Troubleshooting v5.1

The amount of ignition advance built into 1970-1980 BMW Airhead motorcycle was determined

by the automatic advance unit or “ATU”. These varied during Airhead production as emission

controls were introduced. The amount of advance built into the mechanical advance matched the

timing marks stamped on the flywheel. For example, if an ATU had 25° degrees of advance, the

distance on the flywheel between the “S” and “F” marks corresponded to 25° degrees of advance.

The 1970-1978 ATUs were primarily set up for power..The 1979-1980 canister models were

retarded for emission control. While the EnDuraSpark Electronic Ignition replaces the ATU, we

will continue to use the “F” flywheel timing mark for identifying the fully advanced crankshaft

position.

Models

Static

BTDC

Advance

Range

Total

Advance

OT – F

Distance

Early /5

9°

/- 3°

30°

/- 2°

39°

/- 2°

79.8 mm

Late /5

9°

/- 3°

25°

/- 2°

34°

/- 2°

69.6 mm

Some /6, early /7

6°

/- 3°

25°

/- 2°

31°

/- 2°

63.4 mm

Some Late /6 and /7

6°

/- 3°

28°

/- 2°

34°

/- 2°

69.6 mm

1979 – 1980 (canister)

6°

/- 3°

26°

/- 2°

32°

/- 2°

65.5 mm

1981+ (electronic ign)

6°

/- 3°

26°

/- 2°

32°

/- 2°

65.5 mm

After Jan 1, 1978, the static timing mark was retarded from 9° to 6° BTDC for better emission control.

Most 1978 flywheels were mismarked, 4 degrees retarded! A service bulletin describes how to time

engine with marks at the top of viewing hole.

For R65s, reduce the OT – F distances by 78%.

The above chart can be used to determine the total advance in degrees that the “F” mark on the

flywheel corresponds to. It will be one of 31°, 32°, 34°, or 39°. When in doubt, especially for the

ambiguous 1971 and 1978 model years, measure the distance between the “OT” dot and the “F”

line. Then use the last chart column to identify the total advance represented by the “F” line.

Having determined what the stock flywheel “F” line ignition timing is, should it be used “as is”?

Conventional wisdom might say to rotate the timing wheel on the EnDuraSpark timing wheel so

the “F” line is adjacent the timing groove in the timing window under a strobe timing light.

This may not be optimal. Early /5s probably had too much advance; the early /6s too little. The

“sweet spot” for most single-plugged engines is about 34°, which is the default

EnDuraSpark Electronic ignition configuration.

After a high compression Airhead has been dual-plugged the stock advanced ignition timing point

must be retarded. There has been much dialog, testing, and controversy over what the

ideal ignition advance curve should be. After 20 years of discussion, the Airhead

community consensus is that dual-plugged engines should have idle timing near stock

and fully advanced timing of 27 - 28 degrees. This is the second configuration of the

EnDuraSpark ignition black box.

Step 20: Determine “F” Degrees (Full Advance)

Wheel Hub

Original BMW Airhead Ignition Timing Specifications

1 2 ... 20 21 22 23 24 25 26 27 28 29 30 ... 42 43

Comentarios a estos manuales

Sin comentarios

Black Box V5.1 Guía para resolver problemas Pagina 25

Comentarios a estos manuales

Relacionado con productos y manuales para Redes Black Box V5.1