Engine Runs Choppy and Dies Intermittently

Discussion in 'Engine, Fuel and Exhaust' started by devilbiker, Aug 16, 2011.

  1. devilbiker

    devilbiker New Member

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    I have a 1987 Heritage. 1340cc with 11,000 miles on it. My problem is the bike will start but runs really rough. It will idle like that and all of a sudden the engine will run normally, then I can crack the throttle and everything is as it should be, for a minute, Then it begins to run "choppy" again and dies. I have replaced all fuel lines, used new fuel, cleaned and serviced the carb, changed the plugs and wires, changed the coil. Now I am at a loss. I have checked all the wiring and it seems fine. I haven't been able to ride because I can not figure this problem out. Could the ignition be causing it? I have a HI-4 Single Fire Street module. Can anyone help? Also, wondering it it may have something to do with sticking valves?? No engine noise though.
     
  2. HDDon

    HDDon Experienced Member Contributor Retired Moderators

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    Do you still have the original petcock? When you changed all the fuel lines and replaced the fuel did you take the petcock out and clean the screen?
     
  3. BillMull

    BillMull Banned

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    Well, I dont know if this is the problem. I had a similar situation with the bike running funny and revving it would put the bike back to normal and then let off of it and would go back to poor running. I got the carb/break cleaner and sprayed it around my intake to check for leaks. The bike changed drastically in idle to prove of a leak. I bent down and realized my bolt has loosened up over time and I tightened it back up to specs and problem was solved. You may want to check this, it may be the problem or not. At least you will have checked it for future reference anyway. You may discover a bolt is loose, you never know!! I hope you figure out the problem!!! GOOD LUCK brother!:s
     
  4. devilbiker

    devilbiker New Member

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    I didn't take the petcock out when I changed the lines. I will take it off and check it out. I will re-check for any loose bolts and/or leaks too. Thanks!
     
  5. HDDon

    HDDon Experienced Member Contributor Retired Moderators

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    I don't know if your bike has the diaphram type petcock but over time the rubber developes cracks and this will cause the type problems you have. With the bike running have you loosened the gas cap to see if you have a problem with venting of the gas tank.
     
  6. dgannon45

    dgannon45 New Member

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    Check the circuit breaker on the front of the rear fender for loose connections. Take the negative terminal off the battery and tighten all the nuts