Duncan Racing
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Engine Rebuilding Process Engine Rebuilding 2-Stroke Porting 4-STK Cylinder Head Center Custom ATV Builds Machine Shop Services Engine Work Order Form Shipping Tips Engine Rebuilding FAQ
Instructions Technical Documents Rebuild Process & Shipping
2-Stroke Engine 2-Stroke Exhaust 4-Stroke Engine 4-Stroke Exhaust
Shipping Tips Standard Work Order Form Engine Work Order Form Retail Price List How to Ship your Quad Credit Card Authorization Fat Boy 4 Warranty Dealer Application Form DRI Terms
Vortex Warranty Purchase Vortex Vortex ECU Installation and Tuning Tips Technical Documents Who Uses Vortex
History Photos DRI in Print Contact Us
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Services Engine Rebuilding Process Engine Rebuilding 2-Stroke Porting 4-STK Cylinder Head Center Custom ATV Builds Machine Shop Services Engine Work Order Form Shipping Tips Engine Rebuilding FAQ Tech Center Instructions Technical Documents Rebuild Process & Shipping DR IN PRINT Products 2-Stroke Engine 2-Stroke Exhaust 4-Stroke Engine 4-Stroke Exhaust Info & Forms Shipping Tips Standard Work Order Form Engine Work Order Form Retail Price List How to Ship your Quad Credit Card Authorization Fat Boy 4 Warranty Dealer Application Form DRI Terms Vortex Vortex Warranty Purchase Vortex Vortex ECU Installation and Tuning Tips Technical Documents Who Uses Vortex About History Photos DRI in Print Contact Us
Duncan Racing
Duncan Racing International
Shop Products
 
 
2-Stroke Engine
2-Stroke Engine
2-Stroke Exhaust
2-Stroke Exhaust
4-Stroke Exhaust
4-Stroke Exhaust
4-Stroke Engine
4-Stroke Engine
Vortex
Vortex
DR Front Bumpers
DR Front Bumpers
Transmission/Shift Forks
Transmission/Shift Forks
Pyramid Reed Valves
Pyramid Reed Valves
PC 2000 ATC/TRX 250R Cylinders
PC 2000 ATC/TRX 250R Cylinders
KEIHIN Carburetors
KEIHIN Carburetors
Suspension & CROWN Series Brake Lines
Suspension & CROWN Series Brake Lines
Chassis Components
Chassis Components
Accessories
Accessories
Graphics Kits- Decals- Seat Covers
Graphics Kits- Decals- Seat Covers
Clutch Components
Clutch Components
DR MERCH
DR MERCH
GPR Stabilizers
GPR Stabilizers
Controls/Levers
Controls/Levers
 

@duncanracingint

Duncan Racing / Paul Turner Racing Suzuki LT 500 POWERHEAD CNC-Billet-Interchangeable domes- ‘87 6-stud - ‘88-‘90 7-stud. Stock or Ported Cylinders. All bores sizes. Free Tech on proper dome size selection. #nationalporting #graphic
Duncan Racing // Paul Turner Racing 
#HondaCR500 ELIMINATOR port and head modification. Serious HP for the King of big bores! Personally hand ported by LD. #duncanracing #paulturnerracing #bigbore #honda
#tbt Jim Vidmar Wins 2009 Pikes Peak Hill Climb ATV Race! It was the 3rd win at the the famed event for Duncan Racing! #DuncanRacing #Yamaha #Banshee Powered by Duncan Racing #PaulTurner 500cc engine
Duncan Racing ‘85 Honda ATC 250R build. #duncanracing #paulturnerpipes #fatboy2 #silencers #honda #3wheeler #atc250r

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Hours of Operation:

Tuesday-Friday 8:00am -5:00pm PST

*Closed Sat, Sun, Mon

*Available by Appointment After Hours - Call to Schedule!

Duncan Racing International, Inc

9380 Bond Ave Suite B, El Cajon, CA 92021

Phone: 619-258-6306 | Fax: 619-258-6309

sales@duncanracing.com

Contact Us
Duncan Racing International, Inc
9380 Bond Avenue Suite B,
El Cajon, CA, 92021,
United States
619-258-6306 sales@duncanracing.com
Hours
Tue 8am - 5pm
Wed 8am - 5pm
Thu 8am - 5pm
Fri 8am - 5pm

© Duncan Racing International, Inc. 2025 | All Rights Reserved.