PRECISION AND POWER SAVINGS

Save Up To 50% Off!

CLEARANCE SALE

Save Big While Supplies Last

PRECISION AND POWER SAVINGS

Save Up To 50% Off!

CLEARANCE SALE

Save Big While Supplies Last

  • Cars & Trucks
  • Motorcycles
  • Aircraft
  • Boats
  • Radios
  • Batteries & Chargers
  • Parts
  • Part Finder
  • Learn & Enjoy
  • Sale
  1. Home
  2. Brands
  3. OS Engines

O.S. Engines

O.S. Engines

Quality and performance has made O.S. the standard in RC engines for over 80 years.

Filter

Less than $50

1217

Up to $100

267

Up to $250

231

Up to $500

35

$500 or more

22

481-576 of 1773 Results

    Cover Plate: 15CV-A

    Cover Plate: 15CV-A

    $10.99
    Cover Plate: FS-200S-P

    Cover Plate: FS-200S-P

    $25.44
    Crankcase: 35AX

    Crankcase: 35AX

    $48.51
    Crankcase: GF40

    Crankcase: GF40

    $135.64
    Drive Washer: GT55

    Drive Washer: GT55

    $52.69
    Front Plate: Sirius 7

    Front Plate: Sirius 7

    $346.53
    Cylinder Head Gasket, .2mm: 91HZ

    Cylinder Head Gasket, .2mm: 91HZ

    $7.46
    Mixture Control Valve 80T: Sirius 7

    Mixture Control Valve 80T: Sirius 7

    $21.12
    O-Ring Small: 120Surpass

    O-Ring Small: 120Surpass

    $6.49
    Pushrod Cover: FT-120-240

    Pushrod Cover: FT-120-240

    $9.44
    Pushrod Cover: GF40

    Pushrod Cover: GF40

    $14.84
    Piston Pin Retainer P: 40-46

    Piston Pin Retainer P: 40-46

    $6.49
    Piston Pin: FS-91 Surpass
    5(1)

    Piston Pin: FS-91 Surpass

    $10.86
    Piston Ring: GT22

    Piston Ring: GT22

    $25.44
    Reed Valve Assembly: GT33

    Reed Valve Assembly: GT33

    $26.99
    Reduction Gear: FR5

    Reduction Gear: FR5

    $81.96
    Rocker Arm Retainer: FS-20-240

    Rocker Arm Retainer: FS-20-240

    $6.49
    Camshaft Cover

    Camshaft Cover

    $11.80
    Sensor Fixing Screw: GT33

    Sensor Fixing Screw: GT33

    $7.46
    Screw Set (8): 10LA (8)
    4(1)

    Screw Set (8): 10LA (8)

    $8.49
    Valve Throttle WLA-2: GT55

    Valve Throttle WLA-2: GT55

    $15.76
    Valve Intake: FS-120 Surpass

    Valve Intake: FS-120 Surpass

    $37.80
    Lock Washer 5mm

    Lock Washer 5mm

    $19.14
    Breather Nipple: 120-300

    Breather Nipple: 120-300

    $6.49
    Camshaft Gear: FR5-300

    Camshaft Gear: FR5-300

    $44.13
    Carburetor Body: 75AX

    Carburetor Body: 75AX

    $48.51
    Carburetor Insert: 80T, Sirius 7

    Carburetor Insert: 80T, Sirius 7

    $13.83
    Connecting Rod: FS-95V

    Connecting Rod: FS-95V

    $30.44
    Speed Flywheel Key

    Speed Flywheel Key

    $36.84
    Inner Head O.S.Speed B21 Adam Drake II

    Inner Head O.S.Speed B21 Adam Drake II

    $57.75

    Pre-Order

    Thrust Plate: O.S. Speed B2104

    Thrust Plate: O.S. Speed B2104

    $9.53
    Carburetor Reducer 6mm: Speed 21 V-Spec II

    Carburetor Reducer 6mm: Speed 21 V-Spec II

    $20.05
    Carburetor Body: 22B, 21XR-B

    Carburetor Body: 22B, 21XR-B

    $63.18
    Crankcase: R21

    Crankcase: R21

    $119.70
    Crankcase: 30VG

    Crankcase: 30VG

    $87.39
    Cylinder & Piston: 15CV

    Cylinder & Piston: 15CV

    $64.42
    Mixture Control Valve: 12F2

    Mixture Control Valve: 12F2

    $17.16
    Cam Cover: FS155A-P

    Cam Cover: FS155A-P

    $11.91
    Cam Follower: 200 Surpass

    Cam Follower: 200 Surpass

    $22.26
    Carburetor Body: 40K, 46AXII

    Carburetor Body: 40K, 46AXII

    $48.41
    Carburetor Rotor: 70R, FS155A-P

    Carburetor Rotor: 70R, FS155A-P

    $44.34
    Carburetor Rotor: 61HB

    Carburetor Rotor: 61HB

    $26.24
    Choke Shaft: WLA-2, GT55

    Choke Shaft: WLA-2, GT55

    $25.99
    Connecting Rod: GT33

    Connecting Rod: GT33

    $67.42
    Crankshaft: 50SX-H

    Crankshaft: 50SX-H

    $55.12
    Crankcase: 75AX

    Crankcase: 75AX

    $119.78
    Cylinder Liner: FS-40

    Cylinder Liner: FS-40

    $25.94
    Fuel Inlet: #61B, 91HZ

    Fuel Inlet: #61B, 91HZ

    $11.80
    Intake Manifold Assembly: FS-91 Surpass II

    Intake Manifold Assembly: FS-91 Surpass II

    $29.49
    Pushrod Cover: FS-91 Surpass

    Pushrod Cover: FS-91 Surpass

    $10.90
    Pushrod Cover Assembly: FS72 Alpha

    Pushrod Cover Assembly: FS72 Alpha

    $11.80
    Pushrod Cover Set: Sirius 7

    Pushrod Cover Set: Sirius 7

    $29.55
    Piston: 70SZ-H

    Piston: 70SZ-H

    $48.51
    Piston Pin; FS-62V

    Piston Pin; FS-62V

    $11.91
    Piston Pin: FS-90 160

    Piston Pin: FS-90 160

    $10.86
    Piston Ring: FS30S

    Piston Ring: FS30S

    $26.24
    Piston Ring: FS-70 SII

    Piston Ring: FS-70 SII

    $29.49
    Rotor Stop #3A #2A

    Rotor Stop #3A #2A

    $6.49
    Cover Plate Screws (10): 120AX

    Cover Plate Screws (10): 120AX

    $9.85
    Standoff 5x25.4mm 1" (4): GT55

    Standoff 5x25.4mm 1" (4): GT55

    $36.85
    Rocker Arm Support Assembly: FS-20

    Rocker Arm Support Assembly: FS-20

    $10.90
    Main Shaft: 5020-490 .40

    Main Shaft: 5020-490 .40

    $10.99
    Crankcase: 46AXII
    5(1)

    Crankcase: 46AXII

    $52.73
    Crankcase: FS-95V

    Crankcase: FS-95V

    $125.03
    Cylinder Liner: FS-95V

    Cylinder Liner: FS-95V

    $45.01
    Cylinder Liner: 200 Surpass

    Cylinder Liner: 200 Surpass

    $59.03
    Gasket Exhaust: GT55

    Gasket Exhaust: GT55

    $7.46
    M11 Header Pipe Nut: FS070S and FS91S II
    4(1)

    M11 Header Pipe Nut: FS070S and FS91S II

    $6.49
    Silencer Body Gasket: 200 Surpass

    Silencer Body Gasket: 200 Surpass

    $7.46
    Needle Valve Holder Assembly #61B: 91HZ

    Needle Valve Holder Assembly #61B: 91HZ

    $11.80
    O-Ring Rubber Gasket: 120AX

    O-Ring Rubber Gasket: 120AX

    $10.94
    Prop Washer: 40-61
    5(2)

    Prop Washer: 40-61

    $6.49
    Rocker Support: FS110A

    Rocker Support: FS110A

    $29.60
    Valve Spring Retainer: FS-70SII

    Valve Spring Retainer: FS-70SII

    $6.49
    Main Shaft: OMA-3820-1200W

    Main Shaft: OMA-3820-1200W

    $8.99
    Carburetor 61H: GT15

    Carburetor 61H: GT15

    $147.01
    Carburetor HAD313: GT60

    Carburetor HAD313: GT60

    $190.09
    Exhaust Header Pipe Assembly: F6020 FS155A-P

    Exhaust Header Pipe Assembly: F6020 FS155A-P

    $25.29
    Cylinder Head Screws: 56 FS

    Cylinder Head Screws: 56 FS

    $9.85
    Motor Mount: FT120, FT160

    Motor Mount: FT120, FT160

    $44.13
    Rear Bearing: FS120 III
    5(1)

    Rear Bearing: FS120 III

    $33.61
    Carburetor Body: 61T, FS-62V

    Carburetor Body: 61T, FS-62V

    $38.95
    Speed Hex Wrench Ball Driver 2.0mm

    Speed Hex Wrench Ball Driver 2.0mm

    $36.84
    55HZ-H Hyper Ringed .55 Helicopter Engine
    4.5(4)

    55HZ-H Hyper Ringed .55 Helicopter Engine

    $418.63
    Built-Up Parts Set (C&P) O.S. Speed T1204

    Built-Up Parts Set (C&P) O.S. Speed T1204

    $171.28
    Cylinder/Piston/Rod Set: O.S. Max .12 TG Version 4

    Cylinder/Piston/Rod Set: O.S. Max .12 TG Version 4

    $111.36
    Carburetor Reducer 7mm, Red: Speed 21 V-Spec

    Carburetor Reducer 7mm, Red: Speed 21 V-Spec

    $21.10
    T-1070SC L52 Pipe

    T-1070SC L52 Pipe

    $135.44
    TR02 Tuned Silencer Set EFRA2165

    TR02 Tuned Silencer Set EFRA2165

    $227.84
    Cover Plate: 12TG

    Cover Plate: 12TG

    $11.80
    Cover Plate: 105HX-R

    Cover Plate: 105HX-R

    $28.45
    Crankcase: 21XZ-R VII

    Crankcase: 21XZ-R VII

    $152.36
    Cylinder & Piston: 21XZ-B Speed

    Cylinder & Piston: 21XZ-B Speed

    $193.68
    Carburetor Dust Covers: #12FB, 12XZ Speed

    Carburetor Dust Covers: #12FB, 12XZ Speed

    $7.46
    Needle Valve Assembly #12FB: 12XZ Speed

    Needle Valve Assembly #12FB: 12XZ Speed

    $27.29
    Piston Pin Retainer: RX RZ XM

    Piston Pin Retainer: RX RZ XM

    $6.49

    4

    5

    6

    7

    8

    HORIZON HOBBY, WHERE RC MEMORIES LIVE.

    Who We Are.

    At Horizon Hobby, our personal goal is to inspire dreams and build memories. We take pride in providing the best hobby store experience for our customers, whether that’s online, at RC events, or in the RC community with RC cars, RC planes, RC boats, and so much more.

    Our Values.

    Our purpose is simple: deliver WOW moments. By pursuing the best experience through our portfolio of RC cars, helicopters, airplanes, boats, and more, we bring the RC community together in every city, town, and country. We are radio control innovators and Driven is our middle name.

    Our Promise.

    Our promise to our customers is creating one-of-a-kind experiences that keeps you coming back for more. We are more than an online hobby store. Our RC cars and trucks, RC airplanes and helicopters, and other radio control products are with you at home, on the go, and with your friends. We bring the fun.

    Same Day ShippingFree Shipping Over $99Expert Product SupportEasy Returns

    Shop

    • New Releases
    • Our Brands
    • Spektrum Certified Used
    • Fan Gear
    • E-gift Card
    • Vehicle Finder
    • Shop Local
    • Find a Wishlist
    • Trains

    Support

    • Technical Product Support
    • RC Blog
    • Order Status
    • Repairs
    • Product Registration
    • Check E-Gift Card Balance
    • Shipping, Billing & Returns
    • Event Donations
    • Train Support
    • Know Before You Fly
    • Get Help

    Company Info

    • Our Story
    • Contact Us
    • Horizon Brands
    • RC Club
    • Horizon Hobby Visa Card
    • RC Events Calendar
    • Careers
    • Purchasing & Dealer Inquiries
    • Hobbies for Good
    • Affiliate Program

    Legal

    • Privacy Policy
    • Terms & Conditions
    • Site Map
    • Compliance
    • Patents
    • Product Recalls
    • Trademarks

    Sign up & save 10% on your next order!*

    Be the first to know about new products, deals, and events.

    *Some exclusions may apply. First time subscribers only. Your discount code will be emailed to you. By clicking sign up, you agree that you would like information, tips and offers about our events and products. See our privacy policy here.

    Sign up for Horizon Hobby Text Alerts!

    Never miss out - text HOBBY to 44721. Learn More

    Copyright 2025 © Horizon Hobby, LLC

    Our cookies

    This site uses cookies to enhance your web site experience. By continuing to browse or use this site, you are agreeing to our use of cookies. See our privacy policy here.

      Sign up & save 10% on your next order!*

      Be the first to know about new products, deals, and events.

      *Some exclusions may apply. First time subscribers only. Your discount code will be emailed to you. By clicking sign up, you agree that you would like information, tips and offers about our events and products. See our privacy policy here.

      Sign up for Horizon Hobby Text Alerts!

      Never miss out - text HOBBY to 44721. Learn More