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osspeed21vzbv-spec

OS SPEED 21VZ-B V-Spec

OS Speed 21VZ-B V-Spec

Specifications

Variant
Manufacturer OS Engines
Re-branded Engine No
Brand OS Speed
Model 21VZ-B V-Spec
Evolution of OS MAX 21VZ-B V-Spec
Part # 13893
MSRP $469.99
Bore 16.6mm / 0.654in
Stroke 16.0mm / 0.630in
Displacement 3.46cc/0.211cu in
Weight 320.5g/11.3oz

Crank Specifications

Variant
Crankshaft Double Tungsten Slugged/DLC Coated/Silicone Fill
Crank Type 14mm SG Style

Crankcase Specifications

Variant
Rear Bearing Ceramic 14.00 x 25.40 x 6.00
Front Bearing Steel 7.00 x 19.00 x 6.00
Case Cast Aluminum Black Oxide Coated
Backplate Bump Start

Rod Specifications

Variant
Rod Knife edged Aluminum with brass bushing
Rod Length 30mm

Piston/Sleeve Specifications

Variant
Piston/Sleeve Type ABC(Aluminum Piston, Brass sleeve, Chrome Liner)
Intake Ports 3
Exhaust Ports 1

Carburetor Specifications

Uses OS 21H carburetor. Carb Needle settings are default after breakin.

Variant
Carburetor Size 8mm
Carburetor Style Slide
Carburetor Material Aluminum Body with Nylon insulator
Carburetor Adjustment 3 Needle
Carburetor Restrictors 7mm, 8mm, 9mm
Carb LSN -
Carb MSN -
Carb HSN -

Head Button/Cooling Head Specifications

Variant
Head Button Turbo
Supplied Glow Plug OS P3
Cooling Head Black Oxide coated Magnesium

Timing Specs

Intake Rotor Timing Opening 15.5° ABDC
Intake Rotor Timing Closing 74.5° ATDC
Intake Rotor Timing Duration 239°
Transfer Timing Height 3.5mm from BDC
Transfer Timing Duration 114°
Exhaust Timing Height 6.4mm from BDC
Exhaust Timing Duration 114°

TIMING DIAGRAM HERE

Performance

Manufacturer Claimed Peak 2.5ps @ 34,000
X-Dyno Peak Power(HP) 1.5 @ 26,000
X-Dyno Peak Torque(oz-in) 59.82 @ 25,000
X-Dyno Peak RPM Measured 42,750

nitroenginewiki.com_images_ptk2500_xdyno.jpg

Variants

Variant
OS Speed 21VZ-B V-Spec Original, Magnesium cooling head, 21H Carb 320.5g/11.3oz, Part#13893
OS Speed 21VZ-B V-Spec AL Same as original, Aluminum cooling head, 361.8g/12.46oz, Part#13894
OS Speed 21VZ-B V-Spec SpecII Same as original, Drilled Aluminum cooling head, 21J Carb 349g/12.32oz, Part#13811
Protek 321B Samurai V2 Same as Speed, Drilled Aluminum cooling head, 355g/12.52oz, Part#PTK-2500
Ninja JX21 B01 5 port version of speed, OS 28XZ Case, no slugs in crank, Aluminum cooling head, 361.8g/12.46oz, Part#JX21B01
Ninja JX21 B01A Same as original JX, Drilled Aluminum cooling head, 374g/13.19oz, Part#JX21B01A
osspeed21vzbv-spec.txt · Last modified: by nitroadmin