gerkom,

I agree that you are within the compression guideline. I know you said you cleaned the carb already but it seems to be a clogged jet/carb issue. My boy has a 96 YZ80 with a tempermental carb that get clogged easily. I have cleaned it and put it back together and had to clean it again before it worked. I am new to the mini quads but from my understanding the stock carbs are a pain in the butt. Your problem sounds like its in the carb. Let me know if you need me to look anything else up in the service manual. I will be glad to help.

 

Could the fuel level in tank be too low? How about float level? Sounds to me like its too lean, and maybe just having the air filter off will make it too lean. Air/mixture screw could be out of adjustment, or main jet could be partially plugged. Air leak in the intake area?

 

Could the fuel level in tank be too low? - Emptied Tank, new fuel.

How about float level? - Checked it. Float Level OK.

Sounds to me like its too lean, and maybe just having the air filter off will make it too lean. - I agree, it is acting like it is too lean but it did it before I had the air filter off. When I give it a liitle bit of throttle it will die, but it starts right back up. The plug is not wet like the electrical failed. It idles great!


Air/mixture screw could be out of adjustment, or main jet could be partially plugged. - I am going to look at the air/mixture screw. I have looked at all the jet orifices with a magnifying glass and have used brake cleaner and air blasted it. I really don't see any problem with jets.


Air leak in the intake area? - That could be it! I will verify all connections are tight/correct.

Thanks for the suggestions. I'm not going to let this 90cc machine beat me.

Gerry K.
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So you removed the pilot jet and sprayed through it? Replaced fuel filter.
Okay I will get to the point, as far fetched as this seems I'll say your crank seals are bad, since every thing else you have done is perfect. Put the air filter assy. back on and check it out.

You also have not told us how this came to be. After it sat for a while, ran into the lake, ran out of injector oil, just all of a sudden,..........
It could also be a completely plugged up exhaust port. Dirt Dobbers again!
The switch in the throttle assy may be bad or unplugged.

 

Okay I will get to the point, as far fetched as this seems I'll say your crank seals are bad, since every thing else you have done is perfect. Put the air filter assy. back on and check it out. - Could be. I'll check that out but I'm going to check out your other suggestion below first.

You also have not told us how this came to be. - On October 20, 2002 I broke my left leg in five places racing in an Oldtimers race. On February 15, 2003 I went out to the desert with my family to ride for the first time since my accident. I got both my kids going that morning then hopped on my bike and proceeded to break my right leg in four places within the first ten miniutes. That was the last time my daughter rode it. It has always been cold blooded though. I figured that is was just the cold desert. BTW - the quad has an electronic choke ($150 to replace) but I don't see how the choke would keep it from revving.

After it sat for a while - Yes
ran into the lake - No
ran out of injector oil - No
ust all of a sudden - Like I said it's always been cold blooded that first start in the morning.
It could also be a completely plugged up exhaust port - That is a great thought. I will check it out today. It acts exactly like a plugged exhaust (Not to say I've done it, but when you keep the wash plug in and try to start the bike and all it does it idle.)

The switch in the throttle assy may be bad or unplugged - I've taken it apart.

Thanks. I've got my day cut out for me, again!

Gerry K.

 

mine did that it had dirt in the carb and in the reeds. (crappy air filter)

 

Sounds like you need another hobby after breaking both your legs in two outings...

Seriously though, you might just give the shop a call... you can remain anonymous and still look the the mechanics in the eye the next time you walk in for some "REAL" work. They might just have a solution.... seems to me I heard some horror stories about a bad ground on a bike once that acted that way too.... it had enough juice to fire it and let it idle, but couldn't support anything more than that......

good luck

 

Our son's Scrambler 90 throttle assy was corroded which made it die at any time especially right after starting it up or just getting into riding it. My DH replaced and checked ALL that he could, then gave up and took it to ATV shop. They did the same thing as my DH did and sent it home. It still died on our son so back to the shop and they found it was the corroded throttle. Since we were heading to the dunes, they blasted all the corrision out and order the new part. It works great.....except now my son wants to ride the 250EX! (That's another story!)

 

My sons was doing that today it will idle but when you give it gas the engine starts to die out. His would shut off if you held it down too long but it wouldnt start back up. It is also a 2001 model.

 

pull the carb the reeds are next you have dirt in them. mine did the same thing.