FATHER'S DAY SALE ENDING SOON

02d

:

23h

:

03m

:

41s

SEND AN E-GIFT CARD TODAY

The perfect gift. No shipping. No stress.

CLEARANCE SALE

Save Big While Supplies Last

FATHER'S DAY SALE ENDING SOON

02d

:

23h

:

03m

:

41s

SEND AN E-GIFT CARD TODAY

The perfect gift. No shipping. No stress.

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

1238

Up to $100

270

Up to $250

241

Up to $500

36

$500 or more

26

97-192 of 1812 Results

    Rear Bearing: 50SX-H, 55HZ, 55AX
    5(2)

    Rear Bearing: 50SX-H, 55HZ, 55AX

    $34.76
    Needle Ext Cable: FR5 300
    5(1)

    Needle Ext Cable: FR5 300

    $8.49
    Cylinder Head: 55AX
    5(1)

    Cylinder Head: 55AX

    $34.86
    Carburetor Screw: #4D4C2H
    5(6)

    Carburetor Screw: #4D4C2H

    $6.49
    Muffler Mounting Screws #873 (2)
    5(3)

    Muffler Mounting Screws #873 (2)

    $6.49
    Motor Mount: FS52S, 56A
    5(1)

    Motor Mount: FS52S, 56A

    $36.85
    Gasket Carburetor: 61-108

    Gasket Carburetor: 61-108

    $6.49
    Bearing Rear: 65AX

    Bearing Rear: 65AX

    $22.16
    Front Bearing: 61FX
    5(2)

    Front Bearing: 61FX

    $22.16
    Cylinder Head: .35AX

    Cylinder Head: .35AX

    $22.04
    High Pressure Check Valve: 91HZ-R

    High Pressure Check Valve: 91HZ-R

    $21.10
    Carburetor Body: #20H

    Carburetor Body: #20H

    $19.14
    Drive Washer: 91FX

    Drive Washer: 91FX

    $16.09
    Exhaust Seal O-Ring (2)

    Exhaust Seal O-Ring (2)

    $13.78
    Screw Set: FS-48 Surpass
    4(1)

    Screw Set: FS-48 Surpass

    $10.90
    Cover Plate: 15LA
    4(1)

    Cover Plate: 15LA

    $10.86
    Carburetor Reducer 6.5mm, Red: B2101 Speed

    Carburetor Reducer 6.5mm, Red: B2101 Speed

    $21.10
    Cylinder Head Gasket: 35AX

    Cylinder Head Gasket: 35AX

    $6.49
    Thrust Washer: FT-120 160
    5(1)

    Thrust Washer: FT-120 160

    $6.49
    Ratchet Spring #7H #7D #2K
    5(3)

    Ratchet Spring #7H #7D #2K

    $6.49
    Head Gasket: 0.1, 0.15, T1201 Speed

    Head Gasket: 0.1, 0.15, T1201 Speed

    $9.55
    Head Gasket: 15CV

    Head Gasket: 15CV

    $6.49
    Mixture Control Valve 21M

    Mixture Control Valve 21M

    $19.05
    Speed Ball Driver Replacement Tip 2.5

    Speed Ball Driver Replacement Tip 2.5

    $18.53
    M2004SC 85mm Manifold

    M2004SC 85mm Manifold

    $65.28
    Cover Plate: R21

    Cover Plate: R21

    $22.04
    Cylinder & Piston: 21XZ-B

    Cylinder & Piston: 21XZ-B

    $165.99
    Carburetor 61G: 91HZ-R Speed 3D 3C

    Carburetor 61G: 91HZ-R Speed 3D 3C

    $303.60
    Carburetor Body: 22B2, 21XZ-B Ver2

    Carburetor Body: 22B2, 21XZ-B Ver2

    $79.99
    Crankshaft: 21XR-B Version II

    Crankshaft: 21XR-B Version II

    $62.78
    Rear Adapter Fixing Screws (10): 21TM

    Rear Adapter Fixing Screws (10): 21TM

    $7.46
    Dust Cap Set, 18mm (3)

    Dust Cap Set, 18mm (3)

    $11.91
    Piston Pin: 19XZ-B Speed

    Piston Pin: 19XZ-B Speed

    $8.61
    Inner Head O-Ring O.S. T1204 (S30-FKM)

    Inner Head O-Ring O.S. T1204 (S30-FKM)

    $9.89
    T-2080SC II Tuned Silencer Complete Set

    T-2080SC II Tuned Silencer Complete Set

    $270.89
    Crankshaft: 12XZ Speed Spec II

    Crankshaft: 12XZ Speed Spec II

    $119.97
    Cylinder/Piston/Rod: B2101 Speed

    Cylinder/Piston/Rod: B2101 Speed

    $242.95
    Inner Head: 21XZ-R Speed

    Inner Head: 21XZ-R Speed

    $57.96
    Carburetor Reducer 8mm, Red: Speed 21 V-Spec

    Carburetor Reducer 8mm, Red: Speed 21 V-Spec

    $21.10
    M1006SC Manifold

    M1006SC Manifold

    $71.60
    TR02 Tuned Silencer EFRA2165

    TR02 Tuned Silencer EFRA2165

    $184.82
    Crankshaft: 21XZ-B Speed

    Crankshaft: 21XZ-B Speed

    $174.99
    Inner Head: 12XZ Speed Spec 3

    Inner Head: 12XZ Speed Spec 3

    $31.99
    Outer Head: Speed 21 V-Spec

    Outer Head: Speed 21 V-Spec

    $139.99
    Mixture Control Valve 18TM

    Mixture Control Valve 18TM

    $14.73
    Metering Needle Assembly: 30VG

    Metering Needle Assembly: 30VG

    $19.14
    RP6 Turbo Glow Plug Medium On-Road

    RP6 Turbo Glow Plug Medium On-Road

    $14.99
    Crankcase: 12XZ Spec II Speed

    Crankcase: 12XZ Spec II Speed

    $69.99
    Crankshaft: 21XZ-B Spec 2

    Crankshaft: 21XZ-B Spec 2

    $210.21
    Inner Head: O.S. Speed R2104

    Inner Head: O.S. Speed R2104

    $76.71
    Idle Adj Valve STP #6H7L8H

    Idle Adj Valve STP #6H7L8H

    $6.49
    Meter Needle Assembly #12FB: 12XZ Speed

    Meter Needle Assembly #12FB: 12XZ Speed

    $17.99
    Carburetor Reducer 9mm, Red: Speed 21 V-Spec

    Carburetor Reducer 9mm, Red: Speed 21 V-Spec

    $21.10
    Carburetor Reducer 8.5mm, Purple: 21M

    Carburetor Reducer 8.5mm, Purple: 21M

    $21.10
    Rear Bearing: 12

    Rear Bearing: 12

    $21.17
    Crankcase: 19XZ-B Speed

    Crankcase: 19XZ-B Speed

    $157.70
    Crankshaft: 12TG-P

    Crankshaft: 12TG-P

    $50.83
    Inner Head: T1201 Speed

    Inner Head: T1201 Speed

    $37.99
    Heat Sink Head: 30VG

    Heat Sink Head: 30VG

    $91.34
    Pump Plate (PD-09) 2/3 Assembly: GF30 II

    Pump Plate (PD-09) 2/3 Assembly: GF30 II

    $71.58
    Connecting Rod: FS-120 SP

    Connecting Rod: FS-120 SP

    $40.12
    Piston: 37SZ-H

    Piston: 37SZ-H

    $32.56
    Cylinder Head: FS-91-P
    5(1)

    Cylinder Head: FS-91-P

    $81.94
    Radial Mount Standoffs: Sirius 7

    Radial Mount Standoffs: Sirius 7

    $9.44
    Cover Plate: 55AX

    Cover Plate: 55AX

    $17.16
    Needle Valve Assembly: 91SZ-H Hyper

    Needle Valve Assembly: 91SZ-H Hyper

    $29.60
    Lever Metering Pin WLA-2: GT55

    Lever Metering Pin WLA-2: GT55

    $6.49
    Piston Ring: 32FH

    Piston Ring: 32FH

    $26.24
    Piston: GGT10

    Piston: GGT10

    $52.58
    Crankcase: 21XZ-B

    Crankcase: 21XZ-B

    $124.99
    Cylinder & Piston Speed: T1202

    Cylinder & Piston Speed: T1202

    $127.43
    Connecting Rod: Speed B2101, B2102
    5(1)

    Connecting Rod: Speed B2101, B2102

    $52.58
    Crankcase: 21XZ-B Ver2

    Crankcase: 21XZ-B Ver2

    $124.95
    Slide Valve 21M

    Slide Valve 21M

    $32.56
    Outer Head O.S. Speed R2106

    Outer Head O.S. Speed R2106

    $124.99
    Cylinder Head Fixing Screws: 21TM
    5(2)

    Cylinder Head Fixing Screws: 21TM

    $9.85
    Locknut 1/4-M5: FS-52 Surpass

    Locknut 1/4-M5: FS-52 Surpass

    $22.26
    Air Bleed Screw: #40D

    Air Bleed Screw: #40D

    $6.49
    Carburetor Body: #9B

    Carburetor Body: #9B

    $54.64
    Choke Arm Assembly: WLA-2, GT55

    Choke Arm Assembly: WLA-2, GT55

    $7.46
    Crankcase: FT-160

    Crankcase: FT-160

    $174.34
    Crank Pin Stop Screw: Sirius 7

    Crank Pin Stop Screw: Sirius 7

    $22.24
    Drive Washer: GGT10

    Drive Washer: GGT10

    $17.16
    Exhaust Pipe Nut: FS-120 Surpass
    4(1)

    Exhaust Pipe Nut: FS-120 Surpass

    $6.49
    Mixture Control Valve 61H: GT15

    Mixture Control Valve 61H: GT15

    $26.24
    Needle: 15LA

    Needle: 15LA

    $9.85
    Needle 61H: GT15

    Needle 61H: GT15

    $13.78
    Piston Pin: GGT10

    Piston Pin: GGT10

    $22.30
    Piston Ring: FT-120 240

    Piston Ring: FT-120 240

    $29.60
    Valve Spring Retainer: F20-300

    Valve Spring Retainer: F20-300

    $6.49
    Heat Sink Head: 37SZ-H

    Heat Sink Head: 37SZ-H

    $50.72
    Carburetor Body: 61R, FS81 Alpha Pump

    Carburetor Body: 61R, FS81 Alpha Pump

    $87.39
    Cover Plate: 75AX

    Cover Plate: 75AX

    $17.16
    Crankshaft: FS81 Alpha

    Crankshaft: FS81 Alpha

    $73.87
    Drive Shaft: Sirius 7

    Drive Shaft: Sirius 7

    $34.86
    Head Gasket 0.2T: GT22

    Head Gasket 0.2T: GT22

    $7.46

    1

    2

    3

    4

    5

    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