I have an 86 500 with some major problems. It will not run without the choke on. When riding it with the choke in the on position it obviously runs rough spitting and sputtering. As soon as the choke is placed in the off position the motor calms down and then increases rpms till no end. If the choke is not placed back on to choke the motor out or the kill switch applied the motor seems is though the only thing stopping it is self mutilation.

It doesn’t make sense how it can go wide open with the throttle at idle position. Where is it getting the air to run? Is it the reed valves, carb, or power valve? Any suggestions?

Thanks

 

Check your pilot jet. That is the only jet that effects it at idle. Not sure how the weather is there, bu in the winter I start mine at about 1 turn out and fine tune it from there. Also, make sure the fuel line is free of restrictions. If you have an inline filter, you might change it out. When it is running on the choke at idle, take some starting fluid and spray around the intake boot, base gasket, head gasket, spark plug and filter boot. It is obviously leaning out at idle, you just need to find out where

 

There is no '86 LT500r. They came out in '87. It sounds as if you need to rebuild your carb. You've got something foreign in there messing up the flow.

 

clean your carb. Also sounds to me like you have an air leak in a carb boot or base gasket. air is getting into the motor. Also your crank bearing seals can be bad. this is a common problem on the zilla. If you keeo running it lean it will seize.

 

I assume you have checked the intake boot and the main bearing seals. These are the first places to look when you are experiencing an air leak. Make sure your main bearings are OK by grabbing the flywheel and trying to move it up and down to check for play. If there are no air leaks then I have another suggestion. I also own a Quadzilla and experienced a similar problem when my carburator slide was too low. The place on the slide where the idle screw contacts it was wore to the point that it no longer held the slide up high enough to allow the proper air flow.

 

Thanks for the info. I'll check it out.