I have a 04 yz 125 runs great slight flat spot on bottom end plug is med brown any idears

SOURCE: yz 125

go to your local yamaha dealership and buy one for 22 bucks

SOURCE: I have a 95 yz 125 head and 98 yz 125 bottom end.

You have a 50/50 chance that they will work okay. All the mounting holes need to line up and the cooling holes as well. Get a head gasket for the '98 and see if all lines up. Will the exhaust pipe fit the '95?

Puneet Jain

• 90 Answers
• Posted on Jun 17, 2009

SOURCE: yz 125 99 won't run

You need to ensure for the Carburettor Needle fixed, so that the fuel injected out properly, also if the Crank Gasket should be fitted properly.

SOURCE: 2007 125 yz, has a miss before the power valve

There's no extra valve that kicks in to give the bike extra power. The term "power band" is simply referring to the RPM range of the motor that produces the most torque. Make sure the carb is clean and check the spark plug gap and fire. You need a hot blue,purplish fire not a weak white looking fire. If the plug itself is whitish in color you need to richen up the carb if it's black you'll need to lean it out. You should have a chocolate almond color. I'd bet the bike is getting too much air.

SOURCE: i dont no what kind

You mean transmission??? 10w 40 will work, or Bel-Ray makes an oil for that purpose, ask at a bike dealer.