Four-Stroke Yamaha Dirt Bike, Dual Sport & ATV Tech Info on 4Strokes.com

Crockett's BK Carb Mod - This modification is intended to limit the fuel squirt from the carburetor accelerator pump into the engine for an increase in performance and fuel efficiency. By Rob Crockett

2003 YZ450F vs 2003 WR450F - Which bike is right for you. This is a table showing all the differences between the 2003 Yamaha YZ450F and WR450F. By 4Strokes.com

Exhaust Noise Test Data (84KB PDF) - Exhaust noise level ratings for Yamaha dirt bikes with stock and various aftermarket exhaust systems. Go to CA State Parks OHMV Recreation Division Website for latest edition. By John Franger

Installing Lights on the Yamaha TT-R125L - The Yamaha TT-R125, TT-R125L and TT-R125LE don't come with lights and some don't even come with wound stator coils to power lights. By Tom Rogers

Measurement of Exhaust Sound Levels of Motorcycles

Measuring Exhaust Sound Levels (40KB PDF) - SAE Standard for establishing test procedure, environment and instruments to determine sound levels of Yamaha four-stroke dirt bikes. By SAE Motorcycle Committee

TT500 Wiring Diagram (Dual Sport Lighting) (70KB GIF Image) - Complete hand drawn schematic. By Jeff Moon

XT250 (2008) 1,500-Mile Review (Forums) - This is written from a female prospective about a new 2008 XT250. By Ms. Lil' Mynx

XT250 Exhaust Uncork - Derestrict the 2008 Yamaha XT250 stock exhaust system to allow the engine to breathe better. By Ms. Lil' Mynx

XT250 Mixture Screw Plug Removal - How to remove the factory mixture screw plug in the carb of an XT250 so it can be adjusted when uncorking the bike. By Ms. Lil' Mynx

XT250 Tool Kit Screw Replacement - A cheap fix for the tool kit hardware problem on the 2008 Yamaha XT250. By Ms. Lil' Mynx

Yamaha Mini Four-Stroke (to 110cc) Powertrain & Drivetrain Related Specs

Yamaha Mini (to 110cc) Four-Stroke Powertrain & Drivetrain Related Specs (Forums) - By Forums members

Links to Four-Stroke Yamaha Technical Information on the Internet

Alert: Recall 01-04 Raptor YFM660R ATVs for Rear Brake Master Cylinder Reservoir by CPSC
WR426F ('01) - Tips & Tricks by Mike Hobbs
WR450F Airbox Mod by Dan Djokovic
WR450F ('03-'04) - Starter Retrofit Mod by Dan Djokovic
XT600 - Build Your Own CDI Unit by transmic
XT225 ('94) - Upgrade to YZ Pegs by Tracy Hansen
XT225 (94') - Upgrade to Disc Brake by Tracy Hansen
XT225 ('03) - Mikuni TM33-8012 Pumper Carb Install by Scott Bridgman
XT225 ('03) - Upgrade to Disc Brake by Scott Bridgman
XT225R(C) Owner's Manual
XT225-C(D-G) Service Manual

XT225N(C) Service Manual Supplement
XT225 Serow - English Translated Kick-Starter Installation Instructions by Don Verbeck
XT225 Serow: Carburetor Assembly Diagram | Clutch Assembly Diagram | Electrical Circuit Diagrams / Schematics | Gear Lever Adjustment | Head Assembly Diagram | Model Info | Parts Fiche | Starter Motor Diagram by XT225 Serow Riders
XT225 Serow - Make Your Chain Guard / Guide ( Template Download) by XT225 Serow Riders
YZ450F - Project Supermoto by Lance Oliver & Bill Andrews of AMA
Various WR-F & YZ-F Tech Articles by Garrett Berg
YZ-F Auto Decompression E-cam Install by Alan Vinh

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