This is a brand new 181cc light bore up kit manufactured by Kitaco company in Osaka, Japan.
It fits Honda Monkey 125, MSX125 Grom, Supercub C125 and CT125 Hunter Cub.
Please refer to list below for compatibility.
Here are several technical informations from manufacturer:

Product description
BIG BORE KIT FOR STOCK CYLINDER HEAD. POWER / TORQUE INCREASES AGGRESSIVELY IN THE MIDDLE SPEED.
※I-MAP / BIG CAPACITY INJECTOR / HIGH CAMSHAFT (SOLD SEPARATELY) REQUIRED

Notes
○ALUMINUM CYLINDER
○DISPLACEMENT:181cc
BORE O.D.:φ63
STROKE:57.9mm(STOCK)
○COMPRESSION RATIO:11.1:1
○NON-LEAD PREMIUM GASOLINE TYPE

Applicable model

GROM

JC61

JC75

MONKEY125

JB02

SUPER CUB C125

JA48

CT125 HUNTER CUB

JA55


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