User Manual

GS R/C

DLA ENGINE OPERATING-INSTRUCTION

MANUAL

08/20/2014 Copyrighted Material

Page - 23 DLA 32, 58, 64, 116, 116-I2 & 128cc Rev. A.05.01

IGNITION TIMING, SENSOR: (How to set the timing sensor)

The sensor timing is set at the factory to ~ 30

, and you should not have to reset it;

however, depending upon several factors including: altitude, temperature, ultimate tuning for

specific application such as racing, you may want to adjust the timing. Be sure to check the sensor

screws to be sure they are tight and mark the sensor edges with a felt pen for reference.

The sensor timing is set in degrees (

) of crankshaft rotation (counter clock-wise), before Top-Dead-

Center (TDC). TDC is when the piston is at the furthest travel toward the top of the cylinder. A

magnet, which is pressed into the prop-hub, follows the top of the piston and will typically align

with a “landmark” on the crankcase at TDC. As the magnet passes under the sensor, it stimulates

the sensor and sensor generates an electrical pulse which the CDI uses to create a spark in the

sparkplug. The sensor’s electric pulse is represented in the diagram below. The pulse can be

several degrees wide; so, it is important to set the timing on the negative edge of the pulse which is

position where the magnet is “leaving” the sensor.

The timing pulse occurs on the “white-wire”, where the Red = Power, and the Black = Ground-

return. Rotate the prop-hub with timing-line to align it with the TDC line on the crankcase. The

timing is set by loosening the sensor bolts and moving the senor such that the timing pulse’s

negative edge is aligned with the TDC line on the prop-hub. There are special tools to help set the

timing, contact GS R/C for details & ordering.

DLA Timing Sensor Illustration Timing Angle Diagram

The above pictures are for the DLA 32cc and all other engine displacements are similar, with

exception of the 2-cylinder In-line Twin, and the 4-cylinder (QUAD) engines. The 116cc, In-line

and 128cc QUAD engines have two (2) sensors and two (2) CDI’s and each must be set separately,

see table below. The In-line and the QUAD sensor settings are 180

apart and each sensor is set

specifically for the cylinder or cylinder bank that particular sensor is controlling.

where “x” is proportional to the ignition battery voltage

+ x V

~ 0 VDC

The timing is set on the negative

edge of the pulse, where the

magnet disengages the sensor

Where the magnet 1

stimulates the sensor