hi, im new here and to the harley world. i just got my first one about two months ago. ihave put about1500 miles on itand she ran great until abouttwo weeks ago. i went for a ride about 75 miles is all, ran great the whole way until i was almost home,stopped at a stop sign and from then on it is like it is not advancing the timing. idles good, just above idle is good, but if i try to throttle into it at all it just sputters and runs terrible. it is a 1979 shovelhead lowrider 1340 with factory electronic ignition. i started simple and changed plugs, then wires, then coil, then battery, dissassembled and lubed the cintrifical weights, tryed to adjust the timming, checked for loose connections, checked to see if the float was sticking, about the only thing that i can think that would be next would be the ignition itself. any help or suggestions would be greatly appreacitated, thanks!

 

Could be a fuel supply problem. Have you checked the fuel filter?
Got enough gas in the tank?

Scooter

 

You also might want to check the gap on your ignition module. About .004 I believe. You will need a non-magnetic feeler gauge to do this. Most modules either work or they don't.
Also check the air filter element, needs to be clean. You also could have a piece of trash in the mid range jet.
Good luck.

Scooter

 

yes i checked the gap and the fuel filter both are good. as far as the mid range jet thats a good point, i will research the manual and check it out tonight. i did just check the gap with a regular set of feeler gauges though, why non magnetic? thanks for the input!

 

The reason for non-magnetic feeler gauge (brass type) is the ignition module or the pickup has a small magnet in it. If you use a regular steel feeler gauge it will feel tight when it isn't.

Scooter

 

Have you thought about checking leaks around your intake manifold?

 

well i pulled the carb and cleaned the jets and all the ports. everything seemed to be fine. but i was reading the manual and it was talking about a mid range port, as far as i could tell carb cleaner never really did shoot out of it, but i wasnt sure if i was even able to spray through the passageway that leads to it. it is a little hole about the size of a pin head in the top left just after the butterfly starts to open. i also pulled the filter and petcock and cleaned them as well. anyway still runs the same, no change. and in reply to panz4ever no i havent checked for intake leaks, cant you do that by spraying either while idleing and if it revs up that means it is leaking? is it either(starting fluid)or carb cleaner i cant remember? or you should be able to put your hand over carb and it still runs too right?

 

You need to use compressed air and make sure that every port in the carb is open. If you missed one and couldn't get carb cleaner through it, that could very well be your problem.
As far as check the manifold for leaks, you can gently squirt carb cleaner at the intake seams. Try not to let the mist get around the intake side of carb as this will influence the running and fool you. Also be very carefull with the carb cleaner, as it is flammable.

If it changes tone or idle speeds as you squirt around the intake seals you could have a leaky intake seal.
You need to make sure that all passages in the carb are clear of debris though.

Scooter

 

i did use compressed air but i will take it off and do it again. thanks for the input !

 

the carb is clean. 100% for sure. carb cleaner gushed from every port. blew it all out with air, put it back together, minus the air filter, drove it up the street ran great! came home installed the air filter,ran terrible! air filter looks fine, cleaned it anyway, it was a little dirty but not too bad, started it without the air filter again runs great. put the clean air filter on, runs terrible. that is a new one on me. because a few weeks ago it ran fine with the dirty air filter, and now it dont want to run with the clean one. is this something wrong with the carb?