Running on 2 cylinders

[Indy]

have you checked if you still have the O rings under the bowl cover? that would do it for sure.

 

[RxThunder]

yepp, o rings are still there.

 

[Indy]

I cannot think of anything else. We know you took the rack off, and the problem started, that is where I would start. I'm sorry I can't be of more help to you.

 

[RxThunder]

I synced the carbs today and it idles smoother but still popping and backfiring at 6000 rpm. Im going to order new o rings and gaskets and see if thats it. i'm thinking maybe the o rings didnt reseat well. Thanks for your help though, its always good to get other peoples opinions and ideas based on their experiences.

 

[low flying missile]

carbs

Take a close look at the linkage that moves the throttle plates and make sure that the little springs under the sync adjustment screws are all present and accounted for. There was a post from someone a few years back about one of the springs popping out and causing 2 carbs to go way out of sync when the throttle was opened. This would easily cause the backfire and flames you are seeing and the carbs could go back in sync at idle. You didn't remove the black plastic top caps did you? If you did, did you make sure the real tiny O ring got put back correctly.

 

[RxThunder]

Nope, I left the black caps on, also all of thos springs are in place. It is really frustrating because it has to be something I'm doing wrong or the o-rings are bad. So im going to try the o-rings and gaskets, if that doesn't fix it im not sure what to do next except leave it sit the rest of the winter and ride my 05 until I take them back to ohio and have a friend look it over for me. Just would like to have it running since right before winter I did the apex seat swap on it.

 

[Indy]

I forgot to ask, have you put some dielectric on the spark plugs boots? Also unplug the lights and start it in the dark to see if sparks jumping. I had to do the grease even within new coils, that cured a rough funning motor for me.

 

[DV8]

I know you said you have cleaned the carbs, I had cleaned mine a couple times and still had issues like you describe, It wasnt until I took a little wire from a wire brush and a welder cleaning toll and reamed out each hole in the pilot and main jets, that the problem went away, I could see thru the hole in the jet, but there was a film of some sort on them.. Worth a try.

 

[RxThunder]

I just dont see how it could be the jets when it ran fine before and I did not see any dirt in the carbs at all. I'll probably pull it again and go through them, also might throw the carb rack on it from my 05 just to be 100% its the carbs.

 

[Indy]

Thunder, this is what I've tried to say, its happened so many times to me and many other posters, when carbs are cleaned, a lot of times it will breake something else loose and plug a jet or two up again, this is very common. You must pull off both ends of the carbs and clean, great write up in the ty tech area. You didn't mention you have another rack, if cleaning them again does not work, then throw on the other set to eliminate the carbs.

 

[RxThunder]

Well this one through me for a wild loop as if I wasn't lost already. I took the carbs off of my 05 which is running strong, put them on the 03 and now I have the same problem. I know people have said its the exhaust doughnuts or the wire rubbed through in the front, I will check the wire tomorrow but I dont think its that or the doughnuts due to the fact that I ran it right before I took the carbs off and it ran fine. Tomorrow I'm going to try the 03 carbs on the 05 and then put the 05 carbs back on the 05 and make sure both carb racks run good on it. From there..i'm lost...

Almost 50 degrees today, not like I can ride anyways, so much for spending the money and time this fall on the apex seat and risers. And going through both suspensions and changing oil in them both. Also went through my dads sled and a friends sled.

 

[RxThunder]

Okay, I now found the problem, after
i put the 05 carbs on the 03 and it did the same thing I installed them back on the 05 and now the 05 is running the exact same...the problem is clearly me, what am I missing on installing the carbs? I thought I had the throttle cable adjusted right.

 

[jsjk-4-stroke]

sounds like you are not getting the carbs all lthe way on the engine boots or air box not on right , you did plug the wires back in for the carb switch and the plug for the tps switch ?

 

[RxThunder]

Plugged everything back in, carbs are all the way in the boots and I have been trying it with the airbox off, i've ran it before with it off for warming up for an oil change and it always ran fine.

 

[low flying missile]

carbs

Could you somehow be kinking the carb vent hoses when you install them? If you have the airbox off then drain the float bowls one at a time using the drain screw and compare the amount of fuel that each bowl released and let us know.