1989 yz250 starting problem!!

[89yz250]

i tried starting my bike this morning but for some reason it didnt want to start! i tried checking it and pulled the tube that goes to the carb just to check for fuel delivery! No gas came out from it and also pulled my spark plug and no spark at all!Can you guys please tell me whats wrong with my bike and also please tell what to do! doi have to bring it to a shop or can i do this myself? thanks alot guys!!!!

 

[QKENUF4U]

um ok. so turn the fuel on and put the choke on. if you have no spark then you have an electrical problem also. if you cant figure out the electrical problem then its time for the shop.
good luck

 

[nick545]

wow good luck

 

[89yz250]

or do you guys think it's my fuel filter? And also this may sound stupi but, what makes the spark plug spark? Maybe thats the culprit!

 

[nickyd]

try a fresh plug. confirm gas is free flowing. sounds dumb but remove the fuel cap - i have seen them vaccuum close and cut off the fuel supply

 

[TimberPig]

or do you guys think it's my fuel filter? And also this may sound stupi but, what makes the spark plug spark? Maybe thats the culprit!

The flywheel rotor spins around a stationary set of coils mounted to the stator. It causes a charge to build in the coils, one of which produces the spark, and the other acts as a trigger to release it. This is then sent to the CDI, which alters the timing of the spark based upon the RPM's, and releases it to the coil, which steps up the voltage to allow for a hot spark at the plug, the coil sends it to the plug through the plug wire. The kill switch acts by either breaking the coil ground, or by grounding, the coil, to stop the spark.

Your fuel filter is a fine mesh strainer inside the tank at the fuel valve where it leaves the tank. It could be plugged, and is worth cleaning, but also check the tank vent as mentioned, if you remove the cap and hear a whoosh, then your tank vent is plugged.

 

[89yz250]

when i bought the bike the gas cap didn't come with the tube!can you guys tell me what that is called and where can i buy it? My uncle told me that it might be the CDI box that i have to replace! THANK YOU very much guys for all the opinions that you guys have given! KEEP EM' COMING!

 

[TimberPig]

That would be the vent line. It shouldn't be too hard to find a new one.

Your uncle may be right, but I doubt it. CDI's tend to be quite tough, and when they die, normally you will have spark issues, often simply none at all. Until you clean all the connections, test the stator and external coil, and CDI if you have specs in the manual that you need to buy, don't go replacing electrical parts. Ignition parts are very expensive and cannot be returned if you don't need them, or if they are no good. You need to get a manual, and start trouble shooting why it won't run. It will be much cheaper, and more successful if you do it this way.

 

[jdc9q8]

Check this site out for parts..

http://www.bikebandit.com/partsbandit/OEM-Parts.asp

theres some really good diagrams with most all specific parts you're going to need

 

[Nevada Sixx]

i used to have trouble with my 89 125yz,,
i'd check the wires at the kill switch to make sure they arnt grounding against the bars, then check to see you have fuel in your tank, make sure fuel is on, clean carb (including choke).

change plug,, if no spark ( you have to have the plug againt the engine for good ground),,, it could be your stator (under the flywheel).. if you decide to replace it, but the stator coils/plate/wire harness all in one,, easy to replace, mine was 170 bux.

was this bike running when you got it? just got it huh?

 

[Nevada Sixx]

one other thing,, i'd get some fresh fuel, in case its got water in it,, and drain the carb bowl also,, you can get some fuel from the carb bowl, and put some in a glass, and see if there is water in the bottom. use about a 44 to 1 premix ratio.

 

[Nevada Sixx]

dont spend a bunch of money on hoses for your gas cap and carb, just get some tubes from autozone.

 

[89yz250]

thank you ver much guys for the important advices! me and my uncle tested my spark plug this afternoon and found out that it's broken! and i just bought it about a week ago! He said the reason why it broke is because the mixture of the gas was not good at all.I called the guy whom i bought the bike from and asked him what was the mixture of the gas that he put in the tank he said it was 32:1. I dont know if thats goodor bad! And by the way guys whats the best gas to oil ratio mix? Thanks a milion guys for the very important advices!

 

[TimberPig]

32:1 is good on the oil mix.

The fact your plug was fouled out that quickly points to carb tuning issues. If the mix is too rich, plugs will foul out frequently. There's a couple good links on how to jet a bike in the 2 stroke forum.

 

[89yz250]

hey thanks,but to be honest with you i dont know anything about the whole jetting or the jet thing! I'm such a noob but i'm very willing to learn! And one more thing,i remember when i was a kid in the phillipines when i go to the races with my dad and i smell the fumes of the bikes its smells way different than the fumes of my bike! i think my mixtur is really bad!

 

[TimberPig]

You can go here

Jetting Links
to learn how to jet your bike. It isn't hard, but does take some time, and the ability to observe what is going on. Read the lniks, and follow them, and you can easily do it.

The fact you say your bike smells different could mean several different things are to blame. Your mix could be really rich, you may be using a different mix oil, or you could have a bad crank seal letting transmission oil into your crankcases, wehre it is sucked up into the cylinder and burned. This will foul plugs, and cause your ttransmission oil level to drop. If this is the case you need to tear it down and replace the seal, and possibly the main bearings as well. You could also have a bad head or base gasket, which is letting coolant be sucked into the engine and burnt as well. This will normally make white smoke clouds out the exhaust, smell sweet, and your coolant level will drop.

One of the best sources for learning more about bikes is Eric Gorr's book. It will help you immensely. He has some of the information posted on his website Forward Motion link , but the book contains more and better detail in many areas.

 

[dmstafford79]

I have a 89 yz250. Check your WOODRUFF key they shear very easy especially with a torque monster like that. 2 dollars and some change on motoSport.com. Dont forget to set your timing afterwards...