1.

MODEL:

RK125W HOBBY ENGINE

2.

TYPE:

2 STROKE WATER COOLED SINGLE CYLINDER REED VALVE INDUCTION

3.

CAPACITY:

124cc

4.

BORE:

53.6mm FIRST PISTON

5.

STROKE:

54mm

6.

H.P. / RPM

24HP / 15,100 RPM

7.

CARBURETOR:

TILLOTSEN HL-360A

8.

IGNITION:

C.D.I (OPPAMA) TCI, OPTIONAL

9.

IGNITION TIMING:

2.20mm BTDC [STANDARD]

10.

SPARK PLUG:

NDENSO W27ZU [RUN IN ONLY]
W29ES-ZU [RECOMMENDED RACING]

11.

SPARK PLUG GAP:

0.60mm [0.024”]

12.

FUEL OIL RATIO:

16:1 PREMIUM GRADE UNLEADED PETROL

13.

PISTON TYPE:

UNCOATED SINGLE RING

14.

PISTON CLEARANCE:

0.10mm [STANDARD]

15.

RING TYPE:

FLAT TYPE 1mm THICK

16.

RING GAP:

0.25mm [0.010”] MIN.

17.

CYLINDER HEAD VOLUME:

11.2cc

18.

COMPRESSION RATIO:

12:1 [NOMINAL]

19.

CRANKSHAFT:

2 PIECE, FORGED and INDUCTION HARDENED,
FULLY GROUND

20.

CONROD:

100mm STEEL FORGED and MACHINED
TOP AND BOTTOM NEEDLE ROLLER BEARING