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

1215

Up to $100

267

Up to $250

231

Up to $500

35

$500 or more

22

1236-1331 of 1771 Results

    Assembly Screw: 55AX

    Assembly Screw: 55AX

    $9.85
    Pushrod Cover: FS-40 Surpass

    Pushrod Cover: FS-40 Surpass

    $6.99
    Back Plate Gasket O-Ring: FL70

    Back Plate Gasket O-Ring: FL70

    $6.49
    PCV Valve Set: GF40

    PCV Valve Set: GF40

    $14.84
    Piston: 120AX

    Piston: 120AX

    $57.78
    Rocker Arm Support Assembly: FS-40-48S

    Rocker Arm Support Assembly: FS-40-48S

    $11.72
    Rocker Cover: Sirius 7

    Rocker Cover: Sirius 7

    $14.77
    Screw Set (8): 37SZ-H
    4(1)

    Screw Set (8): 37SZ-H

    $9.85
    Bearing R-1350ZZ

    Bearing R-1350ZZ

    $14.99
    Screw Set (12): FS-120 Surpass
    4(1)

    Screw Set (12): FS-120 Surpass

    $17.08
    Main Shaft :3820-1200 .25

    Main Shaft :3820-1200 .25

    $8.99
    Security Ring: OMA-38 Series

    Security Ring: OMA-38 Series

    $5.99
    Carburetor Complete 70T2: GF30 II

    Carburetor Complete 70T2: GF30 II

    $174.34
    Carburetor #10K: 15CV-A

    Carburetor #10K: 15CV-A

    $47.99
    Carburetor 61C: 95AX
    5(1)

    Carburetor 61C: 95AX

    $97.80
    60 Degree In-Cowl Header: FS110A

    60 Degree In-Cowl Header: FS110A

    $40.12
    M16 In-Cowl Exhaust Header Pipe Invrtd 80D: FS200S

    M16 In-Cowl Exhaust Header Pipe Invrtd 80D: FS200S

    $44.22
    Intake Manifold Assembly A: IL-300 Dia Star

    Intake Manifold Assembly A: IL-300 Dia Star

    $36.85
    Center Manifold: IL-300 Dia Star

    Center Manifold: IL-300 Dia Star

    $48.44
    Front Bearing: GT55

    Front Bearing: GT55

    $30.44
    Idle Gear: IL-300 Dia Star

    Idle Gear: IL-300 Dia Star

    $29.47
    Carburetor Body: #61B, 91HZ

    Carburetor Body: #61B, 91HZ

    $75.99
    Carburetor Retainer: 61RX, SX

    Carburetor Retainer: 61RX, SX

    $12.99
    Carburetor Retainer: 55HZ Hyper

    Carburetor Retainer: 55HZ Hyper

    $11.70
    Connecting Rod: 200 Surpass

    Connecting Rod: 200 Surpass

    $48.51
    Rear Cover Plate: GT33

    Rear Cover Plate: GT33

    $34.76
    Cover Plate: 55HZ Hyper

    Cover Plate: 55HZ Hyper

    $11.72
    Cylinder & Piston: 25LA

    Cylinder & Piston: 25LA

    $35.48
    Drive Washer: 21-25

    Drive Washer: 21-25

    $11.80
    Drive Washer: GF30

    Drive Washer: GF30

    $38.03
    Exhaust Cam: Sirius 7

    Exhaust Cam: Sirius 7

    $70.37
    Gasket Set: BGX 3500

    Gasket Set: BGX 3500

    $10.94
    Cover Gasket: 200 Surpass

    Cover Gasket: 200 Surpass

    $6.49
    Gasket Carburetor: FS-120

    Gasket Carburetor: FS-120

    $6.49
    Ignition Module IG-04: GF40

    Ignition Module IG-04: GF40

    $119.78
    Intake Manifold: FS155A-P

    Intake Manifold: FS155A-P

    $38.03
    Intake Pipe AS-R: FT-120 160

    Intake Pipe AS-R: FT-120 160

    $22.30
    Mixture Control Valve: 61ER

    Mixture Control Valve: 61ER

    $29.49
    Exhaust Header Pipe Assembly: 200 Surpass

    Exhaust Header Pipe Assembly: 200 Surpass

    $22.26
    Exhaust Header Pipe Assembly F-4050: FS-62V

    Exhaust Header Pipe Assembly F-4050: FS-62V

    $14.84
    Muffler Extension Screws 120AX (2)
    5(1)

    Muffler Extension Screws 120AX (2)

    $6.49
    O-Ring P3-FKM 61H: GT15

    O-Ring P3-FKM 61H: GT15

    $10.94
    Piston: FS155A-P

    Piston: FS155A-P

    $57.96
    Rocker Arm: FS95V

    Rocker Arm: FS95V

    $28.45
    Rocker Arm Shaft: Sirius 7

    Rocker Arm Shaft: Sirius 7

    $9.44
    Throttle Lever #2CK

    Throttle Lever #2CK

    $6.49
    Allen Head Screws M3.5x12 (10)

    Allen Head Screws M3.5x12 (10)

    $9.85
    Intake Valve: 56 FS

    Intake Valve: 56 FS

    $19.05
    Valve Spring: 20-300

    Valve Spring: 20-300

    $6.49
    Prop Shaft: OMA-50 Series

    Prop Shaft: OMA-50 Series

    $34.99
    Cover Plate with BPS-1 Mount: 55HZ-R

    Cover Plate with BPS-1 Mount: 55HZ-R

    $11.72
    Crankcase: FS155A-P

    Crankcase: FS155A-P

    $174.52
    Crankshaft: 56 FS

    Crankshaft: 56 FS

    $60.65
    Crankshaft: FS-62V

    Crankshaft: FS-62V

    $66.17
    Crankshaft: GF40

    Crankshaft: GF40

    $193.59
    Cylinder Jacket: Sirius 7

    Cylinder Jacket: Sirius 7

    $97.71
    Cylinder Head: FSa-72II

    Cylinder Head: FSa-72II

    $98.83
    Cylinder Liner: 61SX WX

    Cylinder Liner: 61SX WX

    $80.99
    Carburetor Gasket: GT60

    Carburetor Gasket: GT60

    $10.94
    Master Connecting Rod Assembly: Sirius 7

    Master Connecting Rod Assembly: Sirius 7

    $87.29
    Piston: 91HZ

    Piston: 91HZ

    $91.99
    Pilot Shaft: GT55

    Pilot Shaft: GT55

    $29.56
    Piston Ring: 108FSR
    5(1)

    Piston Ring: 108FSR

    $29.60
    Pushrod Cover: FS-95V

    Pushrod Cover: FS-95V

    $17.16
    Rocker Arm Assembly: 120 300

    Rocker Arm Assembly: 120 300

    $32.56
    Rocker Arm: FS-40-48S

    Rocker Arm: FS-40-48S

    $25.44
    Standoff 5x12.7mm 1/2" (4): GT55

    Standoff 5x12.7mm 1/2" (4): GT55

    $29.49
    Complete Carburetor Assembly: (61T2) O.S. FS-64V

    Complete Carburetor Assembly: (61T2) O.S. FS-64V

    $153.99
    Valve Intake: FS-91 Surpass

    Valve Intake: FS-91 Surpass

    $34.86
    Valve Spring: 56 FS

    Valve Spring: 56 FS

    $6.49
    Bearing L-1050ZZ

    Bearing L-1050ZZ

    $17.99
    Main Shaft: 3805-1200

    Main Shaft: 3805-1200

    $8.99
    Propeller Shaft Set: 3815-1000

    Propeller Shaft Set: 3815-1000

    $30.99
    80 Degree Exhaust Header: 155FS-a

    80 Degree Exhaust Header: 155FS-a

    $48.43
    Carburetor Body: #60LH, 50SX-H

    Carburetor Body: #60LH, 50SX-H

    $48.41
    Carburetor Reducer 6.5mm, Blue Aluminum

    Carburetor Reducer 6.5mm, Blue Aluminum

    $21.10
    Carburetor Body: 21J2(B), 21XZ-B Speed

    Carburetor Body: 21J2(B), 21XZ-B Speed

    $89.99
    Crankcase: Speed R2101

    Crankcase: Speed R2101

    $141.93
    Crankcase: 21XZ-B Speed Spec II

    Crankcase: 21XZ-B Speed Spec II

    $157.70
    O.S. Cylinder and Piston Assy Speed B2103 Type R

    O.S. Cylinder and Piston Assy Speed B2103 Type R

    $193.68
    Gasket Head, .2 Aluminum: 21XZ-R

    Gasket Head, .2 Aluminum: 21XZ-R

    $6.49
    Mixture Control Screw #10M

    Mixture Control Screw #10M

    $11.80
    O.S. Metering Needle (21M) R21GT

    O.S. Metering Needle (21M) R21GT

    $17.01
    O-Ring Metal Valve: 120Surpass

    O-Ring Metal Valve: 120Surpass

    $6.49
    202 Elements (4)

    202 Elements (4)

    $13.78
    Carburetor 12F2-B: 12XZ Speed Spec 3

    Carburetor 12F2-B: 12XZ Speed Spec 3

    $118.99
    7.0mm Carb Reducer (Red): AL2 O.S.SPEED R21GT2

    7.0mm Carb Reducer (Red): AL2 O.S.SPEED R21GT2

    $21.99
    O.S. Carburetor Body 22D (B) Speed B2103 Type S

    O.S. Carburetor Body 22D (B) Speed B2103 Type S

    $87.19
    Carburetor Rotor: #2A

    Carburetor Rotor: #2A

    $11.72
    O.S. Crankcase OS Speed R21GT

    O.S. Crankcase OS Speed R21GT

    $185.04
    Outer Head: T1202 Speed

    Outer Head: T1202 Speed

    $102.46
    Outer Head: 12XZ Speed Spec II

    Outer Head: 12XZ Speed Spec II

    $79.99
    Metering Needle Assembly 21M2(B) Speed: R2101

    Metering Needle Assembly 21M2(B) Speed: R2101

    $19.14
    Dust Cover: #2BK
    5(2)

    Dust Cover: #2BK

    $10.86
    Gasket Set: 12TZ

    Gasket Set: 12TZ

    $10.94
    Head Gasket: 0.1, 0.15, T1201 Speed

    Head Gasket: 0.1, 0.15, T1201 Speed

    $9.55

    11

    12

    13

    14

    15

    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