O.S. Speed 1217D 21ZX-B Spec II Ty Tessman 110% Engine

Performance that goes above and beyond!

Champion driver Ty Tessmann firmly believes in always giving 110%, and he expects no less from his power plant. O.S. shares his commitment to excellence, and the result is the Speed 21XZ-B Spec. II Ty 110% long stroke nitro engine. The improvements made by O.S. engineers paved the way for Ty to claim first place at the ROAR Fuel Off-Road National Championships, and this engine is ready to help you ascend the podium as well. The Speed 21XZ-B Spec. II Ty 110% is being produced in limited quantities, so get yours today.

• A real difference-maker for both buggies and truggies!
• Features a 7 mm venturi insert that boosts power while reducing fuel consumption.

• The 4 mm lower cooling head lowers overall center of gravity for improved handling.

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 Ty’s personal involvement with the Speed 21XZ-B Spec. II engine is evident.

0.16" (4mm) lower cooling head lowers center of gravity for improved
handling
21J3(B) slide valve carburetor with 7mm carb reducer that restricts
airflow helping to increase the amount of torque produced

21XZ-B Spec II Ty Tessmann Edition 110% Long Stroke Glow Engine with
Exhaust Gasket, P3 Turbo Ultra Hot Glow Plug, 7mm Carb Reducer,
Decal Sheet, two Dust Caps and Instruction Manual

Glow Fuel: 10-30% nitro content, 20% recommended for break-in
Tuned pipe such as the O.S Engines T-2090SC, OSMG2953
Glow Starter and Track Equipment

Engine;
Displacement: 0.213 cu in (3.49 cc)
Bore: 0.641" (16.27mm)
Stroke: 0.661" (16.8mm)
Practical RPM: 4,000 - 42,000
Weight: 12.45oz (353g) engine only
Crankshaft Size: UNF1/4-28
Distance Between Mounting Holes Same Side: 0.83" (21mm)
Distance Between Mounting Holes Opposite Side: 1.45" (37mm)
Height Bottom of Mounting Tabs/Top of Cylinder Head:
Width at Mounting Tabs: 1.8" (45mm)
Width of Crankcase below Mounting Tabs: 1.2" (31.6mm)
Distance from Backplate to Front Bearing: 2.5" (64.5mm)_
Distance from Center of Crankcase to Front Bearing: 1.7" (44mm)
Distance from Center of Crankcase to Backplate: 0.81" (20.5mm)

Carburetor Settings, NOTE carburetor is preset at factory and
requires very small adjustments
Needle Valve: Approximately 3 turns open from fully closed
Throttle: Approximately 0.5mm open from factory setting with
reducer removed
Metering Needle: Flush with ball link body
Mixture Control Valve: Rotate until slotted head is flush with
carb body