popping thru the carbs

[CoreyCorey73]

I am still having trouble with my eleven special. It pops back through the air filters and backfires out of the exhaust at low throttle. If I rev it up it runs just fine and smooth. I took it to a mechanic and he said that he thinks that the valves need adjusting but another mechanic said that it sounded like the low end jets in the carbs. Can anybody offer any help?

Thanks

[skids]

Popping backwards can be caused by lean conditions in that rpm range. This can be caused by leaks through the manifold boots, plugged idle circuit, rotten-out exhausts, cracks in the exhaust (special models crack at the weld ender the heat shield by the foot peg), or other stuff that I can not comprehend.

[skids]

Popping backwards can be caused by lean conditions in that rpm range. This can be caused by leaks through the manifold boots, plugged idle circuit, rotten-out exhausts, cracks in the exhaust (special models crack at the weld ender the heat shield by the foot peg), or other stuff that I can not comprehend.

[mitch]

Filters

Reading your post i would say that the filters have been changed, was it like that when you got it, who did it,? did it run right after they put the filters on, did they change any jetting to compensate for the filters, Some filters will not run on the xs because of a ridge or lip that blocks the ports on the end of the carbs ! I think if you have it put the air box back on and it will run like a champ HTH.....................MITCH

[CoreyCorey73]

Yes, the person I got it from put K & N Filters on the carbs, but he gave me the air box so I can put it back on. As far as I know they did not change any jetting. I will put the box on and see how that does.

Thanks