Dirt Bike Modifications Forum

My 2000 YZ 125 wont start I tried everything, I cleaned out the carb and what not and I cant figure it out    

change plug.  With a 2-stroke, it's pretty simple.  Plug, fuel or air cleaner.  Even if your carb needs work, it will still start.  May run rough, but it should still fire.   

When did the bike last start?  Can you list the steps you've taken to try to fix the problem?

replace  your plug, then your gas. then make sure the choke is up, or out , then, kick it without touching any throttle...thats the key< if it dont start, give it one full turn on the gas to get the gas in the carb. then choke . and kick..kick..hard, full through..be smooth..if it dont start. then spend alittle time. and call your yamaha dealer. youd be surprised by how they are willing to help you.....Ask for a mec.. and they will give you a  answer on almost anything... no matter what year . or if you bought it there.. TRUST me. Ask your yamaha dealer.just make shure the gas was on..............Got a 2006 yz 250 ..and love it ...had alot of other bikes .    YAMAHA is the best....Just my opinion .............

That depends on the shop.  Some mechanics get paid "flat rate", (by the job), so they don't have time to stand around and try to diagnose a problem over the phone.  If they did that all the time, they'd go out of business.  If you want to eat next week, you better crank out a lot of work. 

Often the only answer they can give you is "you'll have to bring it in and we can take a look at it."  They're not trying to be rude.  But their time is worth something, too.

I've had customers call in, or even walk in the shop unannounced and sneak up behind me.  Then you turn around and there's a guy standing there wanting to ask you some question about his car.  So you give him the best educated guess possible about a car you've never even seen, and he goes out and buys a bunch of parts, slaps them on, and none of them fixes the problem.  So he comes back all mad because "I thought you said you were a mechanic, well this stuff you told me to try didn't work, and blah blah blah..."

That's why it's hard to find a good mechanic these days.

i agree.but it dont hurt to try. im pretty lucky so far. both the yamaha shops here are real good at awnsering questions on the phone. at least the best things to try for the prob. but i know what your saying.  

I always use a simple procedure to find the source of problems with non-starts. 1) check if it has spark, use available tools to ground plug with a buddy. If non-spark use multi-meter to check spark plug for continuity between tip and threads, if there is a reading other than 0 or open lead, the plug is bad, if good test before plug with spark tester, no spark work your way back the ignition system. If you test and have spark at plug move to fuel line to carb and remove if fuel doesnt drain consistantly you move to tank filter and check for the blockage, if it drains consistantly move to card bowl and drain plug, remove and if no fuel drains you know that you have possible stuck float or float valve. I will give you these steps as a base line and they should get you going in the right direction. I am a Yamaha 5 Star Tech and hope this helps but I dont want to get into the carb any farther than the float becouse it takes to long to right out but if you check the steps I have given you it will give you a basis to check the simple stuff.

         

Check the most obvious things.  Sometimes you think something is so obvious that it "couldn't possibly be" the problem, so you skip that step. 

 One time I tried to kick start a bike for 10 minutes, then I realized I left the exhaust plug in from when I last washed the bike.  I removed the plug, and the bike started the next kick.  D'oh!

So, is the exhaust plugged?

Fuel tap turned on?

Air box clear?  No rag in the intake from washing the bike?

Its funny that you said exhuast plug, just 2 weekends ago I was at the track and seen the Motocross track manager from the now defunt Camble Motor Speedway kicking his YZ250 for nearly three minutes and then going thru the whole process of changing fouled plug and venting the engine and then checking the fuel and started kicking again when I noticed that he didnt remove the exhaust plug. I eventualy yelled over to him to pull the plug after holding back my laughter for as long as I could. ElGringo thank you for adding check the simple stuff, I didnt look at it from that angle looking past the basics thinking he would have already ruled out the start up procedures from the manual.