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Discussion Starter · #1 ·
I know there are other postsbut they all seemed pretty old. Picked up this 2007 RKC with only 4700 miles on it and it had Van e and Hines High Output slip on mounted on a otherwise stock motor. Not very impressive to say the least. The decel popping was stupid bad. I had always wondered about the anti reversion therory and fix from DK Customs torque inserts to stop the reversion that DK says is causing the issue especially on big diameter pipes.
Ordered a set and I can say 99% of the po Automotive lighting Automotive exhaust Muffler Exhaust system Rim
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pping is gone and the sound went from ridiculous to a nice rumble. The idlesettled down too. Ilike the look of these big dia pipes. I think I will keep them now
PS it did require some "engineering" to get the to fit but only took a couple of hours.
 

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I know there are other postsbut they all seemed pretty old. Picked up this 2007 RKC with only 4700 miles on it and it had Van e and Hines High Output slip on mounted on a otherwise stock motor. Not very impressive to say the least. The decel popping was stupid bad. I had always wondered about the anti reversion therory and fix from DK Customs torque inserts to stop the reversion that DK says is causing the issue especially on big diameter pipes.
Ordered a set and I can say 99% of the po View attachment 818985 View attachment 818986 View attachment 818987 pping is gone and the sound went from ridiculous to a nice rumble. The idlesettled down too. Ilike the look of these big dia pipes. I think I will keep them now
PS it did require some "engineering" to get the to fit but only took a couple of hours.
sweet....
 

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There are some that love that decel popping and wouldn't have it any other way. Just like the truckers going thru town at 3 in the morning laying on the Jake brake, echoes between the buildings real sweet !
 

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There are some that love that decel popping and wouldn't have it any other way. Just like the truckers going thru town at 3 in the morning laying on the Jake brake, echoes between the buildings real sweet !
The EVO I had sounded just like a jake brake when engine braking. Sold it to my brother and it raised the hair on the back of my neck when he followed me the first time on a ride and he engine braked behind me.
 

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Discussion Starter · #5 ·
There are some that love that decel popping and wouldn't have it any other way. Just like the truckers going thru town at 3 in the morning laying on the Jake brake, echoes between the buildings real sweet !
This was too much pipe for the bike sound. It is still loud but lower in tone and the popping is very subtle. Much better ide and just sounds better going down the road.
 

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1997 Softail Custom (FXSTC)
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Back on my wrecked bike when it had drag pipes, I used those inserts in the end to bring back the low end (bike had straight pipes when I got it and I couldn't afford a new set of pipes at the time). The ones that go in the end of the pipe. When you say torque cones, for a second I thought you were talking about the snake oil inserts that go up by the heads (those don't do anything).

The lollipop baffles in the end of the pipe work, depending on the pipe. There's two things at play, one is the harmonic reversion you mentioned (which could be remedied by as little as a screw or bolt in the end). The big thing these particular inserts do, is increase exit velocity. As soon as exhaust hits the air outside of the end of the pipe, slows way down, which causes a build up in the pipe that has to be overcome (the engine has to push it out, which is why it's more a problem at lower RPM). It's a problem with larger diameter pipes because although more free flowing (good at high rpm), they have a lower velocity (which is why the exit slow down is a bigger problem). The lollipop increases velocity just before where it would slow down as well as increases scavenging in the end of the pipe, helping to prevent that pressure build up.

The result is a smoother bottom end and eliminating some of the low-end sag (assuming it's caused by an exhaust that's too big for the engine and rpm range).
 

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2013 CVO FLHTCUSE8 #414/1100
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What is the part number for the ones you bought? I took those pipes off my CVO because I couldn't hear myself think but I liked the tone. I tuned out the deceleration popping that I first had but went back to the stock CVO pipes that I modified instead. I may try those again if these are cheaper than the actual baffles from V&H.
 

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Discussion Starter · #10 ·
What is the part number for the ones you bought? I took those pipes off my CVO because I couldn't hear myself think but I liked the tone. I tuned out the deceleration popping that I first had but went back to the stock CVO pipes that I modified instead. I may try those again if these are cheaper than the actual baffles from V&H.
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They didnt fit without Some work but i was able to fit them right in the middle. The studcsize is 5/16 x 18 thread. I used to couplers and I found that a 1-1/4" stainless bolts with washer, and lock wash then cut back the insert studs until the bolt and the studs are adjustable to stage ghe insert right in the middle then lock the bolt and lock wS down on the outside. Looks good. There are 2 screw locations on the end of the muffler. I used the two pointing towards the middle at an angle. Drilled a 3/8s hole right through the epty screw hole. Might want to use red goo but I didn't because I wanted to be able to pull it apart. I got the measurements close enough to really tighten it down.
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Yes sir! Blocking the exhaust increases exhaust gas velocity. Someone needs to tell all the racers they been doing it wrong for years.
 
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2007 Ultra Classic (Sophie) vivid black
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Got into this subject on an exhaust thread a few months ago. It got ugly for awhile (FNG's) and led to some heavy reading that almost drove me back to drinking. The main thing I learned was that without a PhD and a machine shop, these are probably going to be the solution.
 

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Discussion Starter · #14 ·
Got into this subject on an exhaust thread a few months ago. It got ugly for awhile (FNG's) and led to some heavy reading that almost drove me back to drinking. The main thing I learned was that without a PhD and a machine shop, these are probably going to be the solution.
Like I was saying when I started the thread. I didn't like the massive popping everytime I let off the gas. Put these in and no more popping. If I get anything else out of it its like getting free beer's.
 

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Got into this subject on an exhaust thread a few months ago. It got ugly for awhile (FNG's) and led to some heavy reading that almost drove me back to drinking. The main thing I learned was that without a PhD and a machine shop, these are probably going to be the solution.
If the OP wanted less noise and is pleased with these results, then this was the right move for him.

My comment was about the absurd advertising that said by plugging the exhaust you increased the velocity of the exhaust gas. Velocity measured where? Around the outside of the plug or the over all exhaust gas velocity?
 

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2007 Ultra Classic (Sophie) vivid black
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I only get a little bit of decel pop every now and then so I'm okay in that area. Do they actually help with low end torque? I'm running true duals and probably losing a lot there. If it gives a boost I will give them a try.
 

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I have Rinehart true duals on my '07 110. I good dyno tune with a TT Mastertune has the engine running great. Good smooth acceleration with no flat spots or hesitation. I get to ride at 2000 - 2200 rpm in 6th gear a lot on our flatter roads down here.
 

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Back in the day a washer was welded to a bolt and attached the same as the cone inserts (lollipops). Did the exact same thing for bottom end torque improvement. This works on jap bikes with gutted baffles just the same. Some people cant comprehend the difference in a race engine vs a street engine. Race engines go straight to WOT to the end of the track, stock, modified engines need to use as much of the available rpm band and gear ratios for street driving. A race engine would not be worth a shit on the street with stop lights, traffic and just dependability. Race engines are not built to go 100,000 miles, they are built to make it to the end of the track then get rebuilt after a few number of runs.
 
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