Some time ago, I installed Fuel Moto's Power Pkg. on my Ultra Limited. This includes the Jackpot Dyno Tuned Mufflers, Stage 1 AC, Headpipe and PC-V. I immediately started getting decel popping and also backfire when shifting from 1st to 2nd and 2nd to 3rd. Jamie and crew have been very helpful but I still get the backfire when shifting. Here are all of the things that I have tried/done:
1. Used the Permatex Ultra Copper Silcone Gasket sealant on the muffler joints and cross pipe joint.
2. Tightened the headpipe bolts so that they can't be tightened anymore (performed this both when engine and pipes were hot and cold).
3. Increased the 0% throttle map position to 15 from 1500-5250RPM. This pretty much solved the decel pop but did lower my overall gas mileage by about 2-3 mpg. Still get the backfire when shifting.
4. Tried setting the throttle map to -10 at the 0% throttle position at the same RPMs. This pretty much solved the backfire but the decel popping was terrible. Mileage went back up by 2-3 mpg.

Fuel Moto has suggested increasing the 0% throttle map to 25 or 30. I have not tried this yet because I didn't want to impact my mpg any more than it has already been impacted. I am very happy with the performance of the Fuel Moto pkg.

I am at a loss as to how to stop the backfiring. Any suggestions?

 

I have the same package on my Limited but have not had any problems with it using the map that Fuel Moto supplied. There has got to be an air leak somewhere in the exhaust to cause the popping. Did you check the gasket at the cross over? How about the O2 sensor bungs?

 

We had a slight popping on decel but they sent a new map by email, hooked the computer to power commander and presto problem fixed. The stage 1 package was a nice improvement over stock.

 

I'd replace the header gaskets if not already done 'as the last step' in the exhaust mods, especially if you had to manhandle the exhaust system to get it into place 'after' replacing the gaskets and torquing the flange nuts.

The relatively low torque values for those nuts, and the easily squished nature of these gaskets, might be where your exhaust is leaking, and consequently be the root cause of the decel pops at this point.
Whenever I do exhaust work I leave the old gaskets in until I have everything else in place (just like I'm finished with the job).
Then I undo the flange nuts, loosen up/remove all the the hangers as needed to get enough clearance to pop out the old gaskets and put in the new ones, tighten up the hangers, and then 'lastly' ......... install the flange nuts (torque per the shop manual) to avoid damaging the gaskets.

 

I have an '09 so I don't need a FM headpipe (no cat in mine.) Other than that, the same mods as you. When I first installed the package I had some decel popping. FM's suggestion was to keep adding 5's to 0% colums at 1500 and up until ithe decel popping goes away I ended up with 20 in the 0% colums from 1500 rpm and up. (below 1500 I have 5.) No decel pop or backfire. The MPG's are 39-40 mixed riding around town and 43-44 mpg hwy. I can't complain about that :-)

Larry

 

Sounds like you still need more fuel, a loss of a few mpgs is cheaper then the damage down the road from running lean.

 

I've never understood the decel-popping issue, as I've never had it except in one minor case that was quickly fixed. Right now I'm using no less than -10 at 0% TP, and only got some decel-popping at 2000 rpm when I had it set to -25 at that point. My bike runs rich at 0% around 2000 rpm and I can smell raw gas when decelerating if set to "0", which is a function of the ECM and the 255 cams, not the PCV. I enrichened it to -15 at 2000 rpms and am now pop-free.

I've run Rush, Jackpot Gen. 1, and Jackpot Gen. 2 mufflers and am now on the Quiet Baffle (right side). I started with a PCIII, then to a PCV, and as of 18 months ago Auto-Tune.
Jamie told me most decel-pop issues are caused by exhaust leakage, but my Rush mufflers never fit the stock exhaust well and I always had leakage out of the right side, but still no decel-popping.

I'm not offering any solutions here that the OP isn't already aware of, but just offering my amazement that some have this problem yet most do not. I would say that it is a function of the mufflers, not the PCV, as if you set the PCV to "0" at 0% TP throughout it would be the equivalent of running with no PCV. That said, I also am sure it is not the fault of the Jackpot muffler design, as I've seen this problem described here using all brands and types, and thus must conclude that decreasing back-pressure is the culprit. This causes reversion, as air that gets sucked back up into the muffler reacts with hot unburned fuel and ignites in the exhaust system. I invite comments on this theory.

 

IMO running lean, even very lean, at 0% TP isn't going to damage anything since you are at 0% only when decelerating and at idle, the former only a small percentage of total running time. Decel-pop isn't going to hurt anything either since it is likely only unburned gas igniting in the exhaust system, probably due to reversion, again IMO.

I doubt if the OP has altered his settings at idle and I would recommend doing so only if you have Auto-Tune or are on a dyno and can monitor the AFR's while running.

 

I would recommend changing the decel area as we suggested and see if it takes care of it. Changing this area will not affect your fuel mileage, you are likely seeing normal variations in mileage which can change signifigantly based on many variables. The injector pw is very small during decel, the duty cycle is generally in the 1-4% range during decel so even if you put 100's in the map in the decel area the actual overall fuel change is extremely small as the PC map represents a % of duty cycle.
Here is how it breaks down, if you take a 2% duty cycle and add 25 in the PC map this would represent +25% and the net result would be a 2.25% duty cycle. This would in no way be enough to affect fuel mileage and any differences from this slight change would only be in effect when decellerating. Essentially a quarter of a % and only when decellerating.

If anyone needs any additional help tuning just let us know, we are here to help.

 

I appreciate all of the responses and iclick is right in that I have not altered my idle settings. As I said in my original post, my current map setting of 15 from 1500-5250 RPM has pretty much resolved the decel popping. I was trying to resolve the backfire occurrence when shifting. I found it interesting that a map setting of -10 resolved the backfire but brought back the decel popping and a positive map setting of 15 eliminates the decel popping but brings back the backfire when shifting. Interesting phenomenon.

I think I will try Jamie's suggestion and go to a positive 20 and see what happens. If I get enough ambition, I may take the whole exhaust system apart again and replace all of the gaskets. I had originally just replaced the crossover gasket and left the head pipe gaskets as original because they looked ok.

But I would rather just be riding.