O.S. Carburetor #21JS Slide 21VZB Speed

Tower Stock# LXVKN8  •  Manufacturer Stock# 23818070
O.S. Carburetor #21JS Slide 21VZB Speed (large view)
Notes from our tech department:
This is the complete 21JS Slide Valve Carb used on the
OS Speed .21VZB and OS Speed 28ZX Engines.


Genuine O.S. replacement parts


One complete 21JS Slide Valve Carb
and Red Carb Reducer
One Rubber Carb Gasket


Installing on engine


Length: 0.94" (24mm) approx. including needle and idle stop screw
Width: 2.15" (54.5mm) approx. including needle and throttle arm
Height: 2.13" (54mm) approx. including needle
Diameter: 0.63" (15.9mm) OD of intake (throat) not including
Carb Reducer
0.35" (9mm) ID of intake (top) including Carb
0.59" (15mm) OD of neck including thermo insulator
(the part that inserts into the crankcase)
0.35" (9mm) ID of neck @ narrowest point (top)
0.42" (10.75mm) ID of neck @ widest point (bottom)


Carb can be identified by its black color and the "21J" marking
on the back side of carb body

cnh 1/2/09

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