I have an '07 Ultra Classic. Since it was new it has always popped on the de-acceleration. I have checked for air leaks and could not find any, but changed out my exhaust gasket any way with no luck stopping the popping. I put a power commander on it, had it dyno several times with no luck. I get good mileage. My friends say they see fire out the pipes when it pops. I have recently put triple 7 cams in and that made it worse. Any suggestions. Could the valves be the problem?

 

sounds like it's way too rich. Check your tune map on the PC

 

Popping on decel is usually a sign of running lean. Might want to try a richer map.



cheers

 

The valves aren't likely the problem. If you didn't retune after the cam change you should. You could try one of two things to get rid of the popping:

1. In the 0% column of the Spark Advance tables (both), increase the value by 5° in the RPM range you have the popping. I haven't tried this technique but some say it often works.

2. Increase the values in both Fuel Adj. tables in the affected areas of 0% TP in increments of five. IOW, if your Fuel Adj. value for 3000 rpm is 5, change it to 10, then 15 until the popping stops. I wouldn't go more than +15.

As LRS suggested, it may be too rich rather than too lean. If going richer doesn't help, put the value back to original and begin the process going downward (-5 at a time). If you aren't comfortable doing these tweaks with the software, take it to your dealer and ask them to dial it out. Or, we can walk you through the process. Be sure to save your original map to your computer in case you want revert to it.

 

Thanks,I'll get it back on the Dyno and try that.

 

Also check intake gaskets, o rings, also check to make sure no part of your exhaust is cracked. that can cause it also.

 

Thanks, Will check.

 

popping on decel can mean lean. But not flames coming out of his pipes. That would kind of indicate there is unburned fuel in his exhaust wouldnt it?

 

That's what I would think.