We went for a ride on our bike and it will start to lug. Sometimes your sitting at a idle and it dies. Everyone that we have talked to wants to buy new parts for it and a mechanic put it on a machine and found nothing wrong with. What do you think it may be.? It reminds me of when my mustang vapor locked on me.

Sounds like the battery is dying. A low battery and/or bad stator or bad regulator will cause the battery to get low on voltage. Although enough to start the bike and idle, it will loose power to the coils under heavy throttle.

check your ignition on the engien could be a bad solaniod or your initin coils are burning up (if they get hot then they can crap out on you)

More likely to be your ignition coils. They heat up and expand this can cause an open circuit which will close up again when it has cooled down. Although, a bad charging system may cause this problem. Check the battery voltage with engine switched off ( approx 12 volts) and with the engine running (approx 14 volts) If you are getting 14 volts then your battery is dead, if you aren't, then your charging system has a fault.

If you are talking about really slow trail riding in low gears,the bike may get hot.If you are still moving along the tracks and getting airflow over the rad, it shouldn't get hot.If you go really slow it might get hot but not if you are still moving at at least 10mph.The fuel/air mix maybe set a little rich.That warms things up.Do not let the bike sit and idle.That will make it overheat.If you stop,turn it off.No exceptions.Hope this helps.:)Mahalo(Does this mean thank you?)Me from Oz

Battery probably! did it push start? because if it did,,,, you should continue to ride it for awhile to recharge the battery.... that is if the voltage regulator is working o.k. check battery voltage, if its only 12v the regulator is probably going out.

sounds if regulator is not working or poor connections within charging circuit

sounds as if you have an issue with the charging system, try using a volt meter to determine if the bike is charging. To do so you will need to access the battery under the seat, with the bike running hook up the volt meter to the battery terminals, at idle you should have around 11volts when reving you should have around 13volts. If not you may have a bad stator or other electrical issues. good luck

I HAD THIS PROBLEM. BIKE WOULD START AND IDLE NO PROBLEM. WOULD GET UP TO SPEED AND DIE. WOULD START AFTER SITTING. BIKE HAD BEEN SITTING FOR A PERIOD.

FIX:: REPLACED FUEL FILTER FIXED THE PROBLEM.

LOCATION::: TUCKED UP ABOVE VOLTAGE REGULATER RECTIFIER IN FRONT OF REAR TIRE LOOKING UP.

no doubt this bike is running very lean at idle. Thats the way the EPA wants it. Im a harley mechanic and i used to work in a US dealer. all carb bikes at set up time had the carbs "readjusted". We drilled out the EPA plug and turned the idle air screw out and drilled out the pilot jet too. The bikes worked much better. we were at sea level too so the bikes were very lean from the factory. I can imagine that after the new legislation that came into force they are even leaner and require a full warm up to run properly. Warmed up means you put your hand on the motors head and its hot enought to have to jerk it away. this could take more than a couple minutes. and yes our "readjustment" was illegal. i advice you to do the same.

If you're talking about dieing at an idle, you can increase the idle slightly to keep this from happening. Do not increase it too much, Harley's are not designed for high idle.