I have posted here about a consistent popping problem I have had with a stage one upgrade and a Vance and Hines Propipe. This all stemmed from a replacement of an older cone shaped Propipe, to a Newer stepped Propipe. The older Propipe was operating fine and sounded great. I have a 2011 Streetglide with a 103 and had upgraded to a Stage 1 with a SE/AC, SEPST, and V&H Propipe. Unfortunately, I was rear ended by a Heritage Softail and had to have the Propipe replaced with the newer version. It's a stepped reduction in pipe size and from the beginning, popped on shifting and decel. I spent 1000.00 dollars on Dyno tuning from every St Louis area/ Metro east HD Dealer, only to have no one be able to tune this out. When the head pipes heated up it pops ... I even sent Copies of the Dyno's to a V&H Tech only to have no help, other than "rich up the fuel". I had another Private shop in Illinois try to tune it, and they did great in improving it but, it's still there. Currently, I'm having the private shop install a T-Man 555 cam and I'm hoping this will stop the popping. I'm in the belief that, that type of pipe is too free breathing for a stock engine with a stage one... I have talked to other people with the same set up as mine and they contend they have no problems. "My configuration pops". So, I will update my post as I get my bike back with the cam install. I'll post the dyno sheet as well. If your Propipe is popping consistently or inconsistently, good luck, I didn't get a lot of help. I spent $, I talked to people, nothing worked. Ultimately, once HD or V&H get your money, your on your own. If it's not an easy fix they won't spend time on you. For those of you who seem to think it's a pipe leak, I've had 3 different Dealers check for it...

 

ral, do you have the pro pipe HO or the Chrome?

 

When the guy hit you from behind, hard enough to screw-up your pipe, do you suppose that the force exerted on the pipe could have cracked something around the exhaust port or maybe the collision transferred enough force to the cylinder heads to displace one or both enough to get air? I'm just reachin' here for possibles.
By the way, why a stage one when you have the sepst? Maybe you got the stage one first then migrated to the tuner.

 

spray some carb cleaner around the (not into) the throttle body manifold,if it gets sucked in you'll here a change in rpm.

 

Have to ask: Are you running a baffle? If not, that could be the problem. Ran into it myself.

 

I have a Chrome Propipe. I spoke with ***** at Drago's Bike Works and he stated that the fact my inner baffle was capped with holes in it, forced the exhaust around the outside of the baffle. We talked about removing that, but I wanted to add the T-Mann 555 cam before I changed the design of the baffle. I'm hoping the cam will change the way the bikes exhaust flows. We'll see how it turns out. I don't know that the previous accident damaged anything. It should have been checked by the HD dealer that repaired it. My Mechanic installing the cam asked if anyone had been in the cam box. Evidently, there were some shims out of place and he was going to have to put everything back together correctly ... We'll see soon. From what I hear, this cam is supposed to wake this 103 up.

 

Lowcountry, I got the SE/AC, SEPST, and the pipes all at the same time with a Dyno to map it. The switch to the newer Propipe was the change causing the popping, as far as I know... I had it Re mapped x3 an no one could help...

 

My bike popped too after exhaust swap. I am running se heavy breather and straight pipes as well in the form of a cobra power port head pipe and some 2011 Cvo touring mufflers with the guts removed, just a straight thru exit. I, unlike you (no offense), installed a power commander v and downloaded some maps and installed a few until I found one that eliminated the popping. The closest one wouldn't pop on decel unless I was in the throttle for a long time in the same gear and it would only pop right toward the end of the decel. Instead of taking it to the dealer or whomever for fine tuning, I took that "dyno" money and spent it on an auto tune for my power commander and all popping stopped after that was installed. I just did 500 miles on the bike on Saturday going thru the north Georgia mountains and the dragon tail and went through all type elevations and some serious temp drops and had no popping at all. Maybe it's time for you to ditch the dyno time and paying someone else to do your work for you and invest in a $60 service manual and a tool kit and learn yourself instead of taking everyone else's word on things. Just my 2 cent.

 

Your bike absolutely needs remapped for the new cams so hopefully you can find a shop that will adjust the decel enleanment value as well as adding more fuel it's going to take with the newer pipe and bigger cams.

BTW, V&H is correct with telling you to richen it up. There are several ways to accomplish that with the SEPST though. Find a good tuner!

 

Check to see how tight your exhauxt nuts are, could be sucking in air