1998 air screw setting - YZ 125 Yamaha Motorcycles

there is no idle screw, idle is controlled by the ecm via the ias(idle air control)

they are ahrd to remove. spray wth penetrating oilf or a week. then use a small slide hammer. screw a screw in the center to pull on. Took me 4 hours. Also, a hot air gun to heat the aluminum case helps. Must be hot like a craft heat tool from Joanne Fabrics. $35 or rent a heat tool for paint. no flame type, just hot air.

There are two causes of your problem that I can think of: firstly, it may be that you, even after changing some jets, haven't got the air/fuel mixture right. If i were you, I'd put the standart jets back in, set the needle position to the middle position, and screw the air/fuel mixture screw 2,5 rotations ( 900 degrees) out from fully screwed in. This should return your bike's mixture settings to approximately standart. Then, using this page http://www.dansmc.com/spark_plugs/spark_plugs_catalog.html
determine if you have a rich or a lean mixture, and adjust accordingly. If you have any more questions, or would like me to clarify something, please ask.

It's simple!...Open glove box door...youll see a plastic shell that is the glove box rear portion. You should find 4, 9/32nds or 7mm (same thing just SAE or Metric) screw heads. Undo four screws and with a flat blade screw driver, gently pry out on shell at either side to clear the door straps. Once clear, just work out of resting place, set aside. You will now see like 5 relays mounted on top of the air handler. Remove bracket that holds four of them + one that is mounted alone. Pull out of the way. Checking both inside and outside, remove all screws, bolts, nuts as it were, until it is obvious there are none left. Now, this is assuming this is where your problem lies! If you are simply having a blower problem, it might be the blower module mounted right beneath and just behind relays on top of air handling box. Just take your time so you dont break anything. Good luck...theroad......

Hi Nortam3842,

Here is a basic list of tool that will get you by.

1.) Tire Iron
2.) Socket Set (or wrenches) I "believe" it's a 8 mm socket.
3.) Screw Drivers

That should be all you need. The tire iron, to take the passenger side tire off to get at the battery, the screw driver to remove the clips on the air box so you can access to top of the battery. The socket set or wrenches to remove the battery, and battery tie down.

Hope I've helped, don't forget to rate.

Lazaruselite