That was what I first thought, but then saw he said muffler clamps. With 68 ft/lbs on the studs he would've needed to start another thread on snapped studs.

 

Well a couple of times I did get a pop upshifting from 2nd to 3rd. Any thoughts?

 

That pop is when unburnt gas hits fresh air and ignites. When you let off the gas with "free flowing exhaust" it creates a slight vacuum and sucks fresh air in the pipe then ignites the unused gas in the pipe. This can lead to exhaust valve damage but most HD use stainless for this reason. This is the difference between tuned and open exhaust. Most don't like the sound of a tuned exhaust they like that rumble including me, but you lose bottom and mid range the only people that run open exhaust is drag racers then it's get it in get it out wide open is all that matters. The best way to get rid of the pop is to lengthen the pipes and put mufflers on

 

After making sure there were no leaks, I had the dealer download their stage 1 software. My setup is similar to yours. After the download the decelerate pop went away and the bike runs great.

 

What exhaust are you running?

 

Yes, exotic cars do it when down shifting, they'll spit flames too.
My Lowrider did it, it was minor and I liked it.
How can you follow (trust) a thread where it is blamed on too lean, too fat or exhaust leaks. Good luck to the OP.

 

Wife and I have been running the Rush 1.75s on our stock 08s for several years now and neither of us has ever had ANY decel pop but I've read where others running the same setup have had the problem. So I'm not sure what luck you would have with them.

If you like the sound of the V&Hs and want to keep them, seems the first thing you need to determine is whether or not you might have an exhaust leak. With enough miles you can see streaks of soot where the slipons clamp to the header pipe. But such is not your case. You could hold the flame of a butane lighter (I use a grill lighter) at the clamp area and look for deflection of the flame. Any sort of smoke source will also work. I've read but never tried a vacumn hose or fuel line hose held up to the ear while moving the other end around the exhaust connection.

I also wouldn't discount the possibility of a leak at your header/exhaust port. Both of my header clamps were loose from the factory. Don't recall if I used a torque wrench on them or just snugged them with a small 1/4 rachet. I vaguely recall that the angle of the nut on the rear one prevented me from using a torque wrench but not sure.

If you find a leak at the slipon clamp pull them and reinstall. I don't know if the V&Hs have the two wings on the header end that the clamp goes over but if so you have to make sure the clamp is far enough forward on these wings to apply the proper clamping force. You could also try lining the end of the slipon with some hi temp RTV. I used permatex ultra copper.

If there are no exhaust leaks and you don't want to live with the decel pop which by most accounts is harmless to the engine, then you may have to try "tuning" it out. I say try because from the posts I've read on the subject, not even tuning is able to eliminate all of their decel pop for some.

Good luck and let us know what if any solution you find.

 

on the 2013 the cat is in the muffler. If you pull on off and look into the part that connects to the head pipe you will see it.

 

It's in the head pipe.

 

V&H Monster Rounds on stock head pipe (complete with CAT), and stock AC.