2003 Yamaha YZ 125 - Page 7 - Answered Questions & Fixed issues

does it stop running if so check the cdi

Is it definetely the crank case, if it is than it is a big job, if its just the outer cover you can start by removing the kick start, cover and anything else in he way and see how much damage there actually is!!! You also have the option of having it welded if parts are too expensive, service manual will give you full details

what is your bike doing

Hi,
I don't know where do you live, but here, in Italy you can buy it
from 1200 to 2500 euros.
http://moto.yakaz.it/yamaha-yz-125-2003
http://auto.trovit.it/auto-usate/yamaha-yz-125
Good luck,
Alex
PS-Don't forget to vote me, thanks!

pull the reeds out and clean them or install new ones.

Hi,
The right spark plug is NGK BR9EG
Alex
PS-Don't forget to vote me, thank you!

Possibilities ::

Head bolts not torqued --

Warped head --

Defective head gasket --

Head gasket not installed properly --

If you want to further discuss, let me know. --

Charlie

03 yz 125 has no valves.

You can buy a new one for around a $100 dollars

your probbly loking at about $1500 for a nice one.

ur clutch basket maybe grooved.... just file the grooves down with a file... but make sure not to take to much off. being that it is a 03 its been done b4... u dont want to much play between the fibers and basket...the fibers should be replaced...good luck

it is possible in a city like bangalore

Intake

lack of clutch fluid.. use 'dot 4' or recommended fluid. remove cap and drain excess fluid out and fill with the new. put cap back on and pump the clutch, clutch will tighten up and after a few pumps clutch should engage fully..

Contact Kustom-kraft.com they can provide you with the sleeve you need, or bore and hone your existing sleeve.

It sounds like the float got stuck in the open position when you went to reassemble the carburator, thus allowing fuel to flow constantly. With the handle end of a screw driver try tapping the bowl a few times. This may free it up, but If the leaking doesn't stop your going to need to take it apart again and check the float assembly again.

Hi there and welcome to fixya,

Try Kaloocan, near minerva trading.. a lot of bikes there. Or find used quality motorcycles at motorcyclephilippines.com

Hope this helps

What is causing the fouling? Engine oil? On a two cycle dirt bike, the fouling can be caused by excessive oil in fuel mix. I believe 50 to 1 is the correct ratio yet you may want to cut back, a little at a time, on the oil or run hotter fuel. The exhaust system will also accumulate enough oil sludge to impede the exhaust flow causing poor performance and plug fouling. A two cycle must breath freely to keep itself internally clean. Air cleaner to exhaust. Proper fuel mix should have little , very little. Good Luckand hopefully this helps you.

32 to 1 >>> 4 ounces two stroke engine oil per gallon of gas.

Not much info to go by, but i'll give some things to check. Got fuel? Got Spark? Got Compression? If you have all these things, after kicking several times, pull plug to see if the plug is wet. If wet dry with compressed air, ground plug on head bolt or use spark tester, Kick engine over while watching plug, it should spark. If not replace and try again. If still no spark, check kill switch with ohm meter to make sure is working properly. If still no spark you will have an electrical issue with either the CDI Box or Stator. If the plug was dry without fuel, pull fuel line from carb. check to make sure fuel is running, if not check fuel shut off valve. sometimes the shutoff valve will clog up. If all is well it has to be a clogged carb.. Good Luck