Trusted PayPal checkout — fast, secure, and familiar.

SAVE
$6.28
Representative image of an RCScrewZ rubber-sealed bearing kit for Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221); exact bearing sizes and quantities vary by RC model.
Representative image of an RCScrewZ rubber-sealed bearing kit for Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221); exact bearing sizes and quantities vary by RC model.
Representative image of an RCScrewZ rubber-sealed bearing kit for Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221); exact bearing sizes and quantities vary by RC model.
Representative image of an RCScrewZ rubber-sealed bearing kit for Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221); exact bearing sizes and quantities vary by RC model.
Representative image of an RCScrewZ rubber-sealed bearing kit for Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221); exact bearing sizes and quantities vary by RC model.
Representative image of an RCScrewZ rubber-sealed bearing kit for Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221); exact bearing sizes and quantities vary by RC model.
Representative image of an RCScrewZ rubber-sealed bearing kit for Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221); exact bearing sizes and quantities vary by RC model.
Representative image of an RCScrewZ rubber-sealed bearing kit for Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221); exact bearing sizes and quantities vary by RC model.
Representative image of an RCScrewZ rubber-sealed bearing kit for Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221); exact bearing sizes and quantities vary by RC model.
Representative image of an RCScrewZ rubber-sealed bearing kit for Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221); exact bearing sizes and quantities vary by RC model.
Representative image of an RCScrewZ rubber-sealed bearing kit for Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221); exact bearing sizes and quantities vary by RC model.
Representative image of an RCScrewZ rubber-sealed bearing kit for Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221); exact bearing sizes and quantities vary by RC model.
Representative image of an RCScrewZ rubber-sealed bearing kit for Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221); exact bearing sizes and quantities vary by RC model.
Representative image of an RCScrewZ rubber-sealed bearing kit for Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221); exact bearing sizes and quantities vary by RC model.
Representative image of an RCScrewZ rubber-sealed bearing kit for Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221); exact bearing sizes and quantities vary by RC model.

RCScrewZ Rubber Shielded Bearing Kit kyo005r for Kyosho Mad Force 1/8 Nitro GP 4WD Monster Truck (31221) | RCX

RCScrewZ

SKU: kyo005r

Regular price
$53.67
Sale price
$53.67
Regular price
$59.95
Shipping, stock & payment info
Quick snapshot of availability, estimated delivery, and our shipping/returns.

Available Quantity: 100

Free shipping on all U.S. orders (USPS Priority Mail).
Ships within 1–2 business days (Mon–Fri); some Saturday shipments by 12:00 PM ET.
Most orders ship from Canton, MI 48187. APO/FPO/DPO & PO Boxes welcome.
Priority Mail typically delivers in 2–3 business days (estimates; not guaranteed).
Easy 30-day returns with prepaid USPS label; refunds issued within 3 business days after the return is received.

Over 99% positive over ~14,000 orders on eBay (last 12 months) — as of October 2025. View on eBay

👇 👇 👇
View Cart & Checkout

This page shows the Rubber-Shielded Bearing Kit for this RC model — view all compatible Screw and Bearing kits for this RC model by clicking this link:

Kyosho Mad Force Monster Truck 1/8 Scale Nitro (#31221) — Compatible Kits by RCScrewZ (Screws & Bearings)

Pro tip: Most builders grab a Stainless Screw Kit and a Bearing Kit for this RC model so everything wears evenly.

Quick Fit Summary
  • Compatible Brand: Kyosho
  • RC Model: Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221)
  • Scale: 1:8
  • Power Source / Fuel Type: Nitro & Glow Fuel
  • Chassis: Kyosho Mad Force ladder-frame chassis (31221)
  • Era: Modern Transition (2000-2009)
  • OEM / Models: 31221
Quick Fit Summary — Full Details

Quick Fit Summary

Key fit details for your RC model, plus what’s in this kit.

RC Model Fit & Specs

  • Compatible Brand: Kyosho
  • Fit: Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221)
  • Compatible RC Model Numbers: 31221
  • Scale: 1:8
  • Power Source / Fuel Type: Nitro & Glow Fuel
  • Vehicle Type: 1/8 Nitro GP 4WD Monster Truck
  • Chassis: Kyosho Mad Force ladder-frame chassis (31221)
  • Era: Modern Transition (2000-2009)
  • RC Model Terrain: Off-Road: Dirt, Grass & Rough Terrain

This Kit Details

  • SKU: kyo005r
  • MPN: kyo005r
  • Product: Sealed RC Bearing Rebuild Kit
  • Bearing Type: Rubber-Sealed (Off-Road)
  • Sealed Bearings: Yes
  • Water/Dust Protection: Sealed against dirt & splash
  • Product Material: Dust-Resistant Carbon Chrome
  • Product Color: Silver
  • Bearing Sizes Included: 6x12x4mm bearings · 8x16x5mm bearings · 10x15x4mm bearings
  • Tips: Seat fully · Do not over-tighten · After wet runs: clean, dry, re-lube
  • Install: ≈60 min; recheck torque after first run
  • Country of Origin: United States
Full Product Description

Exact RC Model Fitment

Confirm the exact RC model and RC vehicle OEM/model number below before ordering.

Compatible RC Model
Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221)
Compatible RC Brand
Kyosho
RC Vehicle OEM / Model Number(s)
31221
RCScrewZ Kit Part Number
kyo005r

Vehicle Compatibility Details

Review these vehicle details to help confirm compatibility with your RC model.

RC Vehicle OEM / Model Number(s)
31221
RC Chassis Compatibility
Kyosho Mad Force ladder-frame chassis (31221)
Compatible Vehicle Type
1/8 Nitro GP 4WD Monster Truck
Terrain Compatibility
Compatible Scale
1:8
Compatible Fuel Type
Nitro & Glow Fuel

What Is Included

Included bearing sizes for this Rubber-Sealed Bearing Kit:

  • 6x12x4mm bearings
  • 8x16x5mm bearings
  • 10x15x4mm bearings

What Is Not Included

Only the bearings identified in the included-bearing-size list are part of this kit.

The RC vehicle and separately sold parts are not included unless specifically listed.

Installation & Model Notes

Rubber Shielded Bearing Kit Compatibility:

Quick Fit Summary:

  • Compatible Brand: Kyosho

  • Fit: Model-specific fitment for Kyosho Mad Force.

  • Compatible RC Model/OEM Numbers: Kyosho Mad Force (31221)

  • Scale: 1/8

  • Power Source / Fuel Type: Nitro GP

  • Battery / Cell Count: Not applicable - nitro engine powered.

  • Drive Type: 4WD

  • Vehicle Type: Monster Truck

  • Chassis: Kyosho Mad Force ladder-frame chassis (31221)

  • Era: Modern Transition (2000-2009)

  • OEM / Models: 31221

  • RC Model Terrain: Off-Road: Dirt, Grass & Rough Terrain

  • Release Date: 2002 Release

This Kit Details:

  • SKU: kyo005r

  • MPN: kyo005r

  • Kit Type: Rubber Shielded Bearing Kit

  • Bearing Type: Rubber-Shielded Bearings (Off-Road / Sealed)

  • Sealed Bearings: Yes

  • Water/Dust Protection: Sealed protection against dirt, dust, and debris

  • Bearing Size Details: 6x12x4mm, 8x16x5mm, 10x15x4mm

  • Product Material: Carbon Chrome Steel Bearings

  • Product Color: Silver

OEM / Model Code / Alias Coverage:

Verified OEM/model code coverage for this listing: 31221.

Model Family Coverage:

Mad Force.

Product Benefits:

  • Rubber shielded bearings add contamination protection for dirt, dust, and debris-prone RC use.

  • A strong choice for off-road, outdoor, parking-lot, restoration, and mixed-surface running.

  • Model-specific bearing kit selected for this Kyosho vehicle rather than a random assortment.

Reason to Purchase:

Choose rubber shielded bearings when protection against dirt, dust, and debris matters more than the lowest possible rolling drag. They are the better choice for off-road, outdoor, dusty, or mixed-surface Kyosho running conditions.

Fitment Note:

Check your Kyosho model number before ordering. This kit is configured for Kyosho Mad Force (31221) and should not be assumed to fit other Kyosho variants unless separately listed.

Search-Friendly Notes:

Kyosho Mad Force, Mad Force, 31221, 1/8 Nitro GP 4WD Monster Truck.

Rubber-Sealed Bearing Kit Details

Review the bearing-kit details below before ordering.

RCScrewZ Kit Part Number
kyo005r
Product Brand
RCScrewZ
Shielding Type
Rubber-Sealed (Off-Road)
Sealed Bearing Status
Yes
Bearing Material
Dust-Resistant Carbon Chrome
Approximate Piece Count
Color
Silver

Before Ordering

  • Confirm your exact RC model, RC brand, and OEM/model number whenever possible.
  • Review the included-bearing-size list before purchase.
  • Read the installation and model notes before disassembly or installation.

Vehicle versions, chassis revisions, and model-year configurations can differ.

Confirm fitment before purchase when your RC vehicle differs from the details shown above.

Fits: Kyosho Mad Force 1/8 Nitro 4WD Monster Truck (31221)
$53.67

Trusted PayPal checkout — fast, secure, and familiar.