Hey guys. Im new to the Quad world. You can research my past threads to see how that happened. When i got my quad running, it ran great till yesterday. I obviously didnt tighten the flywheel tight enough, and it came loose on me and died when i was a mile or so from the house. It ended up shearing the key. I replaced the key this morning, and the bike started right up and ran great. But, as soon as it got warm after 2-3 minutes of riding, it started sputtering, not idleing, and dying if i didnt keep it revved up (it was similar to a car when the carb loads up and you have to rev it to get it cleaned out). When the bike dies, it backfires right afterwards. I cannot get it started back up unless i hold it at WOT when i kick it, and when it starts, it sputters its way up in the RPM range till it finally clears up. As soon as i let the revs get lower again, it tries to die. Throttle response is poor at the low RPM range, but power is there when the revs are up. I snapped a pic of the plug so you all can diagnose it for me. Plug Pic

Let me know what you think.

 

I tore everything apart behind the flywheel, put it all back together and went for another ride. I rode around the yard for several minutes, and it did fine. Went back into a trail a little ways, it did fine. Went a little farther.....it started its bullcrap again. Almost like its out of gas. Got it started a few times and made it almost all the way back to the house, but had to push it the last 50 yds.

I got back to the house and read in the manual that the tank CAN be overfilled? Is this true? I just filled it up yesterday (i run 40:1 yamalube and premium gas). I will try draining some out of the tank to see what happens.

 

Well, gee, thanks for all the help there guys [img]i/expressions/face-icon-small-wink.gif[/img]

Draining gas didnt help. I didnt figure i would be that lucky.

I pulled the carb, went completely through it, pulled the reeds, but they dont look too good. I think i read somewhere that you arent supposed to see light through the ends of them. Well, i can see alot of it. I may pick up another set monday if the dealer has them in stock.

Could the reeds cause this kind of problem? Why would it start now?

 

Was there alot of crud in the float bowl? Sounds like the pilot jet is plugging up,( wont idle , backfires when dies, needs throttle to start). Try pulling the choke on, when it wont idle and see if that helps. If it does...then the pilot jet is plugged. Its possible the reeds are bad... but i dont know how to explain why that would cause intermittent problems. If they were bad, the symptoms wouldnt come and go.

 

The problem happens when the bike warms up. It starts, runs, and idles perfectly when i first start it, and for the first few minutes of riding. But as soon as i start to romp on the throttle, its like it loads up with fuel and it dies. Now its getting to the point that it wont restart even with throttle. I have to wait till it cools down then it all starts over.

The exaust smells really rich too. what would suddenly cause a rich condition? Its kinda odd that this starts as soon as i fill it up with premium gas. I was running regular when it was running right.

What kind of symtoms do you get when reed valves go?

 

Well girls. I found the problem. After rebuilding the carb, flipping the reed valves, disassembling the stator twice, and numerous things, i found out that it was a portion or the wire harness that i had run too close to the pipe. I found this when i fiddled with the harnes some and all of the sudden it runs. So i start fiddling with it while it is running, and the friggin thing nails me when i grab the part by the pipe. It felt like i wa hit by the plug wire. I repaired the heat damaged part of the harness, and zip tied everything up out of the way. IT runs great now.

While i had the carb and reeds off, i put on a reed spacer. I can tell a difference. Alot more bottom end. It did seem to loose some top end, but i really dont care about that.

Let this be a lesson for everyone. Check the stupid little obvious stuff first!!!!

 

well power i Have a TRX250ex That is doing the same thing it will crank when its cold and run good for a few minutes and then it will start backfiring, and it will die if i dont give it gas ... so thanks for the info im going to go home and try it today, ( fingers crossed)