250 has a nasty lean condition I cannot figure out.

[conig]

OK. i have an 85 250es big red and here is what happening.

air box lid on or off I get the same thing. with the trike running warm or cold in any gear if I peg the throttle off idle the trike just dies. I can roll on the throttle and it seems to run fine. the bike will not die with the choke about halfway on.

With the above I figured it was just a lean condition so I cleaned the carb(several times ) and it hasn;t gone away. Over the weekend I also rebuilt the carb and still I have this problem. I even put a main jet in for the pilot jet and a main jet in the main jets position and I am still having this problem go wide open and it dies.

If I pull the choke half way out and the bike seems to run fine. It does this weither the gas is turned to on or Res. I have flushed the tank with fresh gas and refilled it with new fuel.

Could inproperly adjusted valves cause this? how about incorrect oil? I recently changed my oil but I don;t know for sure the stuff I used was for wet clutches seems the problem occuring in neutral would rule out the clutches the oil was the proper weight. I also cannot find any air leaks at all to cuase this lean condition. I am at this point really out of ideas. I have ran the bike so it can't just be a cold engine.

[MTS]

Get the proper piolet jet size, go 2 size's bigger and go from there.

[conig]

I have the proper size two of them but the problem was worse, I then switched an extra main jet to see if it would make a difference and it did but it was a negligible difference.

and do you mean two sizes bigger on the pilot or main? I have to be over two sizes bigger on the pilot with a main jet in there, I would assume anyway.

[conig]

im really wondering if anything outside the carb could cause this I have gone through the carb with a fine tooth comb.

[Jason Hall]

Make sure your not sucking air around the intake boot.

[G-MAN-1]

make sure your getting fuel?
maybe something in the way.

[conig]

checked and checked could valves have anything to do with this? or could a coil/ timing issue coause this?

im at a huge loss as to what this could be.

[conig]

ok so I spent all weekend playing with this thing. could it be a coil?

removed all rust from the tank and treated it, cleaned the petcock, cleaned carb again removed all jets and they all are ok. put in a bored out main jet. and still had my problem but experienced some intake back firing.

any good places to pick a coil up?

[trikezilla]

I had this problem on the 125M: In my case it was only a faulty plug!! You proble checked that though.

[slow200s]

coil would have nothing to do with the carb if you are running lean make sure your carb is the correct one and that there are no cracks in the tubes connecting to it