Complete PDF version of the Service Manual for the Yamaha YZ125T. A MUST for every YZ125 owner.
Download: Immediately after payment!
OEM Original factory workshop manual.
Models covered by this manual: 2005-2007
Number of pages: 259 pages
Table of contents:
This PDF repair manual can be downloaded right after the payment process in complete, on the device of your choice. You will also receive the download link by email along with your receipt.
We do not offer printed manuals, for the following reasons:
- it is more eco-friendly to use a digital version
- your manual never gets dirty or greasy
- you can always choose to print the specific page(s) you need to work on your bike
- you receive your manual immediately after payment
- it is searchable
The Yamaha YZ125 is a motocross racing motorbike with a two-stroke 124.9 cc (7.62 cu in) displacement single-cylinder engine manufactured by Yamaha since 1974. It is open to the general public. It was built with twin rear shocks for the first two years, then switched to a monoshock. The YZ125 has won five AMA National Motocross Championships and several AMA Regional Supercross Championships.
Yamaha introduced the four-stroke YZ250F as a companion to the YZ125 in 2001. The two motorcycles share a rolling chassis and are qualified to compete in the same racing class. The YZ250F has a modest horsepower edge.
The YZ125 is powered by a 124 cc (7.6 cu in) two-stroke reed valve engine. From 1974 to 1980, it was air cooled, and since 1981, it has been liquid cooled. It is equipped with a Mikuni 38 mm TMX series carburetor. The engine generates 35 horsepower (26 kW).
Depending on the model year, the YZ125 is equipped with a five- or six-speed manual sequential gearbox. The clutch on the 2005 model is a wet, multiple-disc coil-spring clutch with a constant-mesh mesh.
From 1973 through 2004, the YZ125 used a single steel backbone frame. It typically weighed between 176 and 198 lb (80 to 90 kg). Yamaha upgraded to a single backbone frame made of aluminum alloy for the 2005 model year. The dry weight was reduced to 190 lb as a result of the frame material modification (86 kg). The wheel components and front fork suspension were revised for 2008 models, resulting in considerable weight reductions and a wet weight of less than 200 lb. Aluminum-framed YZ125s are noticeably “flickable,” which might be considered as a disadvantage because they become more difficult to manage on uneven surfaces.
The YZ125 had a standard telescopic fork tube until 1988, when it was replaced with the first upside-down fork in 1989. A large number of riders, including AMA Champ Dom Barbuto and his brother Nick Barbuto, as well as X-Games medallist Kyle Ford, have picked this as their go-to bike. Richard Rich, an 11-time Nationals champion and Eli Tomac competitor.