20 Most Recent 2003 Yamaha TT-R 125 Questions & Answers

download the repair manual here
http://www.torrentreactor.to/search/haynes+yamaha+ttr+125+repair+manual

You have to remember that there are a few sets of gears that might be worn and you say that they do not appear to be worn have you tried to kick the bike while looking at the gears ( kicking the bike with out any spark plugs will make it easy to operate the leaver because there will be no compression in the motor) .

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Sounds like your piston rings are damaged and you need an engine rebuild

The degree of difficulty depends on your mechanical ability and the tools you have to work with. The main tool you will need is a valve spring compression tool. It is sort of like a "C" clamp and compresses the valve spring to allow the two valve cotters to be removed. Once removed the rest of the valve assembly just comes apart. Be sure to seat the new valve using valve grinding compound. When removing the head, be sure to have the piston at TDC compression. Note the position of the timing mark on the OHC gear. Don't let the chain drop into the gear box. Hook a wire to it so it can't. Please rate my answer.

remove the cable and make or buy a new one ( depending on the fittings could use a pushbike brake cable and solder )

Check to see if something is causing the float in the carburetor to stick, which could be preventing fuel from filling the bowl up.

If it is a 00 - 06 Yamaha TTR125/TTR125E it is 116 link.

If it is a 00 - 06 Yamaha TTR125L/TTR125LE it is 122 link. I’m happy to help further over the phone at https://www.6ya.com/expert/al_e83b1941f9c0f302

The small wheel uses a 116 link chain. the big wheel uses a 122 link chain.

Yamalube

Spray some light oil, or WD-40 into and around the lock assemble, this should help rid of moisture.

Hi,
You can download it from here:
http://www.manuale-pdf.it/telechargement.php
Hope this help...
Best regards,
Alex
PS-Don't forget to vote me, thanks!