Two Brothers "popping" during deceleration

[bababang]

All

I put on the two brothers M2 cans. They sound great but I have alot of popping when decelerating. I've read on formum, leaking air maybe the problem and the stock cans did a great job hiding the pop sound. Just wanted to weigh this in and hear other opinions and suggestions. I know a certain amount of popping is OK, but this seems to be more then I would expect.

thanks

 

[GeorgiaRoller]

I get virtually no popping on mine. But I did add the P1 tips and it smoothed out the sound even more but they still sound great when you get on the throttle. You may want to try them.

P1 Tip 4-5db reduction

P1X Tip 7-8db reduction

 

[ahchiu]

All

I put on the two brothers M2 cans. They sound great but I have alot of popping when decelerating. I've read on formum, leaking air maybe the problem and the stock cans did a great job hiding the pop sound. Just wanted to weigh this in and hear other opinions and suggestions. I know a certain amount of popping is OK, but this seems to be more then I would expect.

thanks

You need to remove your PAIR system, on deceleration it opens a valve to let air into your exhaust, for a quick fix you can unplug your PAIR so it won't open (unplug the electrical to the PAIR)

 

[TomInPA]

Deceleration popping is typical for a lean A/F condition and can be cured with a revised fuel map (Power Commander or similar). You can also reduce popping by eliminating the exhaust air injection system (PAIR) and ensuring the exhaust header gaskets are well sealed. Since the new pipes flow a bit more air than stockers, you may actually experience some miss-fires that allow fuel to be sucked into the exhaust where it ignites. This is the popping you hear. This is especially true when decelerating and vacuum is very high.

 

[Queensland Ken]

Just remove all the air induction system including the solenoid and fit some rubber blanking off caps.

You will need 4 X 1/2 inch caps, and one 5/8 inch cap, from an automotive acc shop.

The 5/8 cap for the air box, the 1/2 caps for the cam cover.

 

[garyahouse]

All

I put on the two brothers M2 cans. They sound great but I have alot of popping when decelerating.

thanks

I was just thinking that even though I chose Staintunes, I WAS looking at the Two Brothers cans. The Two Brothers looked really nice on the website. I was pleasantly surprised to note that there's no popping during decelerating with the baffles in-ever, but there is some popping with the baffles out for the first couple minutes while the bike is cold. After that, nothing, not a single "pop," once the bike is warmed up.

So,Bababang, let me ask you, does this popping occur all the time or just when bike is cold and needs to get warmed up?

Gary

darksider #44

 

[someguy]

ok... riding a 10...

slipped a set of two brothers on and i had some minor popping and found i had an air leak between the factory pipe and the slip on. i added a bit more permatex and don't have any popping.

i didn't change anything else...

so what gives? haven't touched the "PAIR" system or changed anything...

another question: if it's popping, is that bad?? sorry if thats a dumb question...

 

[RadioHowie]

another question: if it's popping, is that bad?? sorry if thats a dumb question...

It's not "bad"...just the exhaust system equivalent of beemerdons, i.e., terminally annoying.

 

[Pegsparks]

I removed the PAIR system on mine when I put on new cans and was under the tank doing a TB synch and plugs. I used these caps to block off the valva cover. They are heavy duty vacuum caps, not the cheap ones at the parts stores. I did use the parts store 5/8 cap for the air box because it wasn't subjected to as much heat.

https://www.fastenal.com/web/products/detail.ex?sku=0162611

 

[kamal]

Excellent 'how to' here: https://www.fjrforum.com/forum/index.php?showtopic=106119

I also used caps, rather than hose + plugs.

Go for it!

Al

 

[Collin]

...or you could just go low tech with two boxes of "Bulldog" steel wool and a broom handle. Just keep ramming it in there till you achieve the desired result. Works great.

 

[Richouse]

I have a set of 2 Bro's pipes and experience some popping on decel also although it is not to bad. I have also removed the PAIR system (which helps) and bumped up the fuel ratio with the barbarian jumper mod which helped. I can guarentee that your engine popped on decel with stock settings and stock pipes. The pipes just did a great job muffling it. So some popping will be normal. Those 2 Bro's are VERY open compared to stock. Take off your PAIR system and bump up your fuel some using a power commander or Barbarian mod and ride. Or don't do anything and just listen to it pop...

 

[GeorgiaRoller]

Well even though I really didn't notice too much popping on my TB can's I decided to go ahead and remove the pair system on my bike tonight. I went to my local Napa Parts Store and picked up:

- Part# 660-1697 1/2" Rubber Radiator Hose Caps (4ea)

- Part# 660-1696 5/8" Rubber Radiator Hose Cap (I got 2ea but you only need 1ea for the job)

It was a piece of cake to remove the pair hose system and the caps worked perfectly. Should be good to go now. Total cost on the caps was about $13.00

I did test fire the bike up afterwards and it did sound cleaner with no minor popping going on at fast idle anymore.