OS Engines® Replacement RC Nitro Engine Parts

A selection of replacement parts for OS Engines®. These parts are not original parts unless otherwise stated in the descriptions. Please check your choices thoroughly.

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Replacement Parts Price Quantity
Single Row Ball Bearings - 20x37x9 mm - Stainless Steel AISI 440C - Replaces -
OS Engines® FSR RC W-Muffler - 50: BB 20-37-9
OS Engines® FSR Ring RN - 108: BB 20-37-9
OS Engines® RX - 21: BB 20-37-9
OS Engines® RX-2 Cycle - 15: BB 20-37-9
OS Engines® RX-EFI - 21: BB 20-37-9
OS Engines® RX-FI - 140: BB 20-37-9
OS Engines® FSR RC W-Muffler - 50: Bearing - Stainless Bearing Sealed Option
OS Engines® FSR Ring RN - 108: Bearing - Stainless Bearing Sealed Option
OS Engines® RX - 21: Bearing - Stainless Bearing Sealed Option
OS Engines® RX-2 Cycle - 15: Bearing - Stainless Bearing Sealed Option
OS Engines® RX-EFI - 21: Bearing - Stainless Bearing Sealed Option
OS Engines® RX-FI - 140: Bearing - Stainless Bearing Sealed Option

Replacement Part: S6904-2RS (PK-20)
Double black rubber sealed standard stainless steel bearing

Single Row Ball Bearings - 20x37x9 mm Unflanged - Stainless Steel AISI 440C Bearing

$546.95
Temporarily Out Of Stock -> Backorder now for delivery around Aug 13, 2026
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Single Row Ball Bearings - 20x37x9 mm - Chrome Steel SAE 52100 - Replaces -
OS Engines® 108 FSR - 2 Stroke: BB 20-37-9
OS Engines® RX140: BB 20-37-9
OS Engines® 108 FSR - 2 Stroke: Replacement Rear Bearing - Standard Bearing
OS Engines® RX140: Replacement Rear Bearing - Standard Bearing

Replacement Part: 6904 (Each)
Open standard bearing

Single Row Ball Bearings - 20x37x9 mm Unflanged - Chrome Steel SAE 52100 Bearing

$13.05 $15.65
Temporarily Out Of Stock -> Backorder now for delivery around May 26, 2026
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Single Row Ball Bearings - 20x37x9 mm - Chrome Steel SAE 52100 - High Speed Polyamide Cage - Ceramic Si3N4 Balls - Replaces -
OS Engines® 108 FSR - 2 Stroke: BB 20-37-9
OS Engines® F320 4 Cylinder RC - 4 Stroke: BB 20-37-9
OS Engines® F4 4-C - 320: BB 20-37-9
OS Engines® F4 4CYL - 32: BB 20-37-9
OS Engines® FF240 4 Cylinder RC - 4 Stroke: BB 20-37-9
OS Engines® FSR RC W-Muffler - 40: BB 20-37-9
OS Engines® FSR Ring RN - 50: BB 20-37-9
OS Engines® FT 12 Twin RC 4C - 45: BB 20-37-9
OS Engines® FT Twin 120 II - 45: BB 20-37-9
OS Engines® FT Twin RC 4C - 12: BB 20-37-9
OS Engines® FT Twin RC 4C - 120: BB 20-37-9
OS Engines® FT12011 Twin RC - 4 Stroke: BB 20-37-9
OS Engines® FT160 Twin RC - 4 Stroke: BB 20-37-9
OS Engines® Old FF 4 CYL - 61: BB 20-37-9
OS Engines® Old FT Twin 4C - 240: BB 20-37-9
OS Engines® Old FT Twin 4C - 25: BB 20-37-9
OS Engines® RX - 21: BB 20-37-9
OS Engines® RX140: BB 20-37-9
OS Engines® RX-2 Cycle - 15: BB 20-37-9
OS Engines® RX-EFI - 140: BB 20-37-9
OS Engines® RX-FI - 21: BB 20-37-9
OS Engines® 108 FSR - 2 Stroke: Replacement Rear Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® F320 4 Cylinder RC - 4 Stroke: Replacement Rear Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® F4 4-C - 320: Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® F4 4CYL - 32: Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® FF240 4 Cylinder RC - 4 Stroke: Replacement Rear Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® FSR RC W-Muffler - 40: Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® FSR Ring RN - 50: Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® FT 12 Twin RC 4C - 45: Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® FT Twin 120 II - 45: Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® FT Twin RC 4C - 12: Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® FT Twin RC 4C - 120: Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® FT12011 Twin RC - 4 Stroke: Replacement Rear Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® FT160 Twin RC - 4 Stroke: Replacement Rear Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® Old FF 4 CYL - 61: Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® Old FT Twin 4C - 240: Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® Old FT Twin 4C - 25: Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® RX - 21: Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® RX140: Replacement Rear Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® RX-2 Cycle - 15: Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® RX-EFI - 140: Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer
OS Engines® RX-FI - 21: Bearing - High Speed Economy Ceramic-Hybrid Bearing - Polyamide Retainer

Replacement Part: 6904-CSN-T9H-ECO (Each)
Open economy ceramic-hybrid bearing with a high speed polyamide retainer

Single Row Ball Bearings - 20x37x9 mm Unflanged - Chrome Steel SAE 52100 - High Speed Polyamide Cage - Ceramic Si3N4 Balls Bearing

$94.14 $112.96
Temporarily Out Of Stock -> Backorder now for delivery around Jun 26, 2026
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Single Row Ball Bearings - 20x37x9 mm - Chrome Steel SAE 52100 - Replaces -
OS Engines® 1.08 FR RC W-Muffler: BB 20-37-9
OS Engines® AX 120 - 46: BB 20-37-9
OS Engines® F320 4 Cylinder RC - 4 Stroke: BB 20-37-9
OS Engines® F4 4-C - 32: BB 20-37-9
OS Engines® F4 4CYL - 32: BB 20-37-9
OS Engines® FF240 4 Cylinder RC - 4 Stroke: BB 20-37-9
OS Engines® FSR RC W-Muffler - 40: BB 20-37-9
OS Engines® FSR RC W-Muffler - 50: BB 20-37-9
OS Engines® FSR Ring RN - 108: BB 20-37-9
OS Engines® FSR Ring RN - 50: BB 20-37-9
OS Engines® FT 12 Twin RC 4C - 40: BB 20-37-9
OS Engines® FT Twin RC 4C - 12: BB 20-37-9
OS Engines® FT Twin RC 4C - 45: BB 20-37-9
OS Engines® FT12011 Twin RC - 4 Stroke: BB 20-37-9
OS Engines® FT160 Twin RC - 4 Stroke: BB 20-37-9
OS Engines® RX - 21: BB 20-37-9
OS Engines® RX-2 Cycle - 15: BB 20-37-9
OS Engines® RX-EFI - 140: BB 20-37-9
OS Engines® RX-EFI - 21: BB 20-37-9
OS Engines® RX-FI - 140: BB 20-37-9
OS Engines® RX-FI - 21: BB 20-37-9
OS Engines® 1.08 FR RC W-Muffler: Replacement Rear Bearing - Standard Bearing
OS Engines® AX 120 - 46: Bearing - Standard Bearing
OS Engines® F320 4 Cylinder RC - 4 Stroke: Replacement Rear Bearing - Standard Bearing Shielded Option
OS Engines® F4 4-C - 32: Bearing - Standard Bearing
OS Engines® F4 4CYL - 32: Bearing - Standard Bearing Shielded Option
OS Engines® FF240 4 Cylinder RC - 4 Stroke: Replacement Rear Bearing - Standard Bearing Shielded Option
OS Engines® FSR RC W-Muffler - 40: Bearing - Standard Bearing Shielded Option
OS Engines® FSR RC W-Muffler - 50: Bearing - Standard Bearing Shielded Option
OS Engines® FSR Ring RN - 108: Bearing - Standard Bearing Shielded Option
OS Engines® FSR Ring RN - 50: Bearing - Standard Bearing Shielded Option
OS Engines® FT 12 Twin RC 4C - 40: Bearing - Standard Bearing
OS Engines® FT Twin RC 4C - 12: Bearing - Standard Bearing Shielded Option
OS Engines® FT Twin RC 4C - 45: Bearing - Standard Bearing
OS Engines® FT12011 Twin RC - 4 Stroke: Replacement Rear Bearing - Standard Bearing Shielded Option
OS Engines® FT160 Twin RC - 4 Stroke: Replacement Rear Bearing - Standard Bearing Shielded Option
OS Engines® RX - 21: Bearing - Standard Bearing Shielded Option
OS Engines® RX-2 Cycle - 15: Bearing - Standard Bearing Shielded Option
OS Engines® RX-EFI - 140: Bearing - Standard Bearing Shielded Option
OS Engines® RX-EFI - 21: Bearing - Standard Bearing Shielded Option
OS Engines® RX-FI - 140: Bearing - Standard Bearing Shielded Option
OS Engines® RX-FI - 21: Bearing - Standard Bearing Shielded Option

Replacement Part: 6904-ZZ (Each)
Deleted Item. Available while stocks last.

Single Row Ball Bearings - 20x37x9 mm Unflanged - Chrome Steel SAE 52100 Bearing

$3.64 $10.30
31 Available Now -> Only the available quantity may be ordered online. No backorders.
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Single Row Ball Bearings - 20x42x12 mm - Chrome Steel SAE 52100 - High Speed Polyamide Cage - Replaces -
OS Engines® FX - 240: BB 20-42-12
OS Engines® FX - 240: Replacement Rear Bearing - High Speed Economy Bearing - Polyamide Retainer

Replacement Part: 6004-Z-T9H-ACO-ECO (Each)
Single shielded economy bearing with a high speed polyamide retainer and light anti-rust lubricant

Single Row Ball Bearings - 20x42x12 mm Unflanged - Chrome Steel SAE 52100 - High Speed Polyamide Cage Bearing

$52.14 $62.56
Temporarily Out Of Stock -> Backorder now for delivery around Jun 26, 2026
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Single Row Ball Bearings - 20x42x12 mm - Chrome Steel SAE 52100 - Replaces -
OS Engines® 140 RX - 2 Stroke: BB 20-42-12
OS Engines® 160 RX - 2 Stroke: BB 20-42-12
OS Engines® 140 RX - 2 Stroke: Replacement Rear Bearing - Standard Bearing
OS Engines® 160 RX - 2 Stroke: Replacement Rear Bearing - Standard Bearing

Replacement Part: 6004 (Each)
Open standard bearing

Single Row Ball Bearings - 20x42x12 mm Unflanged - Chrome Steel SAE 52100 Bearing

$7.50 $9.00
Temporarily Out Of Stock -> Backorder now for delivery around May 26, 2026
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Single Row Ball Bearings - 20x42x12 mm - Stainless Steel AISI 440C - Replaces -
OS Engines® FX - 240: BB 20-42-12
OS Engines® FX - 240: Replacement Rear Bearing - Economy Bearing Shielded Option

Replacement Part: S6004-ZZ-ECO (Each)

Single Row Ball Bearings - 20x42x12 mm Unflanged - Stainless Steel AISI 440C Bearing

$12.59
3 Available Now -> Orders for more than 3 can be expected around Jun 21, 2026
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Single Row Ball Bearings - 20x42x12 mm - Chrome Steel SAE 52100 - Replaces -
OS Engines® FX - 240: BB 20-42-12
OS Engines® FX - 240: Replacement Rear Bearing - Standard Bearing Shielded Option

Replacement Part: 6004-ZZ (Each)
Double shielded standard bearing

Single Row Ball Bearings - 20x42x12 mm Unflanged - Chrome Steel SAE 52100 Bearing

$11.95
2 Available Now -> Orders for more than 2 can be expected around May 26, 2026
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Single Row Ball Bearings - 22x44x12 mm - Chrome Steel SAE 52100 - Replaces -
OS Engines® BGX-1 Ring RN - 46: BB 22-44-12
OS Engines® BGX1-Ring - 46: BB 22-44-12
OS Engines® BGX-3500 - 46: BB 22-44-12
OS Engines® FP - 32: BB 22-44-12
OS Engines® BGX-1 Ring RN - 46: Bearing - Economy Bearing
OS Engines® BGX1-Ring - 46: Bearing - Economy Bearing
OS Engines® BGX-3500 - 46: Bearing - Economy Bearing
OS Engines® FP - 32: Bearing - Economy Bearing

Replacement Part: MR4422-ZZ-ECO (Each)
Double shielded economy bearing

Single Row Ball Bearings - 22x44x12 mm Unflanged - Chrome Steel SAE 52100 Bearing

$53.50 $64.20
Temporarily Out Of Stock -> Backorder now for delivery around Jun 26, 2026
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Single Row Ball Bearings - 22x44x12 mm - Chrome Steel SAE 52100 - Replaces -
OS Engines® 3500: BB 22-44-12
OS Engines® 3500: Replacement Rear Bearing - Economy Bearing

Replacement Part: MR4422-ECO (Each)
Open economy bearing

Single Row Ball Bearings - 22x44x12 mm Unflanged - Chrome Steel SAE 52100 Bearing

$49.32 $59.18
Temporarily Out Of Stock -> Backorder now for delivery around Jun 26, 2026
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