View Full Version : 78 ironhead

10-15-2010, 11:24 AM
I have a stupid question. I have almost finished my 78 ironhead and everything was going good, untill I started getting a lot of popping when I rev the engine to higher rpm them idle. It idle just fine. I have checked everything and can not figure out what it is. Any suggestions? New plugs, timing is good, plenty of fuel. Any help would be nice, sometimes when you have been working on something to long you miss the obvious.


10-15-2010, 12:02 PM
I would check if you have an intake leak, and double checking you pushrod adjustment wouldnt hurt

10-18-2010, 6:42 PM
What ^^^ he said. And switch out the condenser.

10-21-2010, 12:37 PM
what kind of carb you got on it.?

10-21-2010, 12:43 PM
I am running an s&s. I have adjusted the pushrods which helped alot. It runs and drives with no popping, until I run it in high rpm. I am going to check the intake and see if there are any leaks and replace the condenser.

10-21-2010, 3:25 PM
when you take it apart to check for leaks get some permatex non-hardening gasket maker and coat the inside of the seals before it goes back together and let it set up before you start it

10-21-2010, 6:17 PM
try changing your main jet too a larger size & double check your accelerator pump

10-21-2010, 10:07 PM
ya check your main and your slow jet, there are many size combos you can use. I live in CO so I had to change mine up on my S&S carb on my 72 shovel. It made a world of difference,

10-22-2010, 5:41 AM
like stated but i'd also double check your point gap between both lobes wide and small. one could be right and one could be off so you'd need to split the difference.

10-23-2010, 9:05 AM
what did you find out?

10-23-2010, 9:57 AM
Are you running electronic ignition or points?
If you're running electronic, make sure you have resistor plugs and wires.

10-23-2010, 5:17 PM
Got it I went back through the ignition, and readjusted the points, and timing agian to make sure. Everything seems to be working good know! Thanks guys for all your help!!