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  Electric Motors, Engines & Accessories > Engines Glow Fuel > Engines R/C Glow Fuel Car 2-Stroke - .0 -.15 Bookmark this Page

O.S. - OSMG1991 OSM11680 11680 531028020771 4531028020771
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Easy RC: Engines

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O.S. 12XZ Spec II Speed Tuned Engine
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O.S. 12XZ Spec II Speed Tuned Engine
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On-line Videos: Video 1 (5.1 MB)
Instruction Manuals: Manual 1 (2.7 MB)

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Tech Notes
This is the O.S. 12XZ Speed Tuned Spec II Engine.


Special coating on crankshaft reduces friction and wear
Tungsten weights for better balance at high RPM
Machined aluminum outer head with holes drilled for lighter weight
and better cooling
Newly designed crankcase and liner port for increased torque at low
to mid speed
12F(B) slide valve carburetor


O.S. 12XZ(P) Speed Tuned Spec II Engine, Carburetor, 5.5mm Carb
Reducer, RP6 Turbo Glow Plug, Exhaust Gasket, two Dust Caps and
Instruction Manual


Fuel: 10-30% nitro content, 20% recommended for break-in
Exhaust System: Depending on vehicle
Air cleaner assembly, glow starter and track equipment


Displacement: 0.128cu in (2.0cc)
Bore: 0.543" (13.8mm)
Stroke: 0.55" (14.0mm)
Practical RPM: 5,000 - 44,000
Power Output: 1.75 PS, 1.73 HP @ 35,000rpm
Weight: 7.76oz (220g)
Height from crankcase bottom to top of cylinder head: 3.54" (90mm)
Height/crankshaft center to top of cylinder head: 3.01" (76.6mm)
Width including mounting tabs: 1.53" (39mm)
Width not including mounting tabs: 1" (25.4mm)
Width between mounting holes same side: 0.43" (11mm)
Width between mounting holes opposite side: 1.23" (31.4mm)
Cylinder head diameter: 1.93" (49mm)
Length of exposed crankshaft: 1.16" (29.5mm)
Length from backplate to front bearing: 1.96" (50mm)
Length from backplate to end of crankshaft: 3.1" (79.5mm)
Internal thread size at end of crankshaft: 1/4-28
Carburetor Settings:
Needle Valve, Approximately 2-1/2 turns open from fully closed
Throttle Stop Screw, Approximately 1mm visible from carb throat
Mixture Control Valve: Rotate until slotted head is flush with
carburetor body
(Make adjustments only in small increments. Refer to manual for
full break-in and carburetor adjustment instructions)


Some notes on Slide Valve and Rotary Carburetors:
Rotary Carbs offer a larger response in the middle of the power
band. This works well for off-road applications when throttle
response must be varied.
Slide Valve Carbs provide greater response at the beginning and end
of the power band. This works well for on-road and racing
applications for fast take-offs and high speed.

jxs 08/20/10

– If you need more information, use these O.S. resources –
Web Site:
Phone: 217-398-8970
  Postal Address:

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Accessories Needed
This is the O.S. 12XZ(P) Speed Spec II Engine. FEATURES: Special crankshaft coating reduces friction & wear, tungsten weights for better balance at high RPMs, machined head with holes for lighter weight & better cooling, 12F(B) slide valve carburetor REQUIRES: Fuel and track equipment, exhaust system depending on vehicle

Accessories for the O.S. 12XZ Spec II Speed Tuned Engine

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 LXRXC9 Tower Hobbies TOWER Power 20% Car Fuel Quart
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Subtotal for this Group of Accessories: 10.69  

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