Bad popping sound from pipes?

[thumper29]

Hello All,

I have one question?

(1) I just got a 07 K-9 and when I road it home the bike was making a popping sound from the pipes. The sound is so loud that people behind me think it’s a gun going off. Can anyone tell me what that is and why because I’m being told that they all do that but one of my friends has a Chopper and his doesn’t do that.

I need some HELP badly because I just spent over $800.00 on new pipes and that didn’t change anything. The popping sound is still there but not as bad.

:bang:

 

[Thumper169]

You have an exhaust leak, pull the pipes and install new gaskets or go with the Harley gaskets and double them up, problem solved more than likely, if this easy repair isnt it I would lean toward jetting, what altitude are you at and what is your jetting?

 

[IrishGuy]

I had the same thing happen to me when I changed out my pipes. Stepping up the jets solved the problem for me :2thumbs:

 

[K9Anniv]

I had the same thing happen when the dealer switched out my stock pipes for the BDM Slip-Ons (made by SuperTrapp, by the way). He had to re-jet my carb and went back through to check and tighten all exhaust clamp bolts. Problem solved, for the most part...still get a few pops, but not nearly as bad.

 

[woodbutcher]

the nuts that hold the pipes to the heads tend to get loose. to help prevent this, torque them to spec. and then put a second jam nut on them. and yes, they will probably pop some anyway no matter what you do. you can get rid of most of it but not all.

 

[Ratman]

Cannot find torque specs in service manual. Anyone know what the torque setting should be (V&H Big Radius)? Discovered mine were loose yesterday after suggestion to check from Raywood. On the way now to get jam nuts. THANKS!

 

[LDO]

Sorry,
I can't remember them either but I would check out the HOW TO's section. I believe Gasman did one on changing out your exhaust.

 

[V]

http://www.bigdogbiker.com/forums/technical/11198-torque-specs.html

There ya be! Arr is Friday

 

[Ratman]

Faster than a speeding bullet! Thanks!

 

[oldfool]

Check the spark plugs. My chopper was doing the same thing and it was the old worn out plugs.

 

[TheDeadOne]

Previously mentioned issues all correct to cause popping.

Minor causes for popping - fouled plugs, exhaust leak, too lean - jet up.

Good Hunting & Good Luck! :2thumbs:

 

[Thumper169]

Sounds like you have had plenty of good info, all posts are right on track!!

 

[bruce]

If the loud popping is on deceleration, my sure your new pipes have the baffles in,

 

[thumper29]

I just wanted to say THANKS for all the info!

 

[BLITZKRIEG]

All Good answers but it Could also Be an Intake Leak.....
The Pop is caused by Cool air Mixing in the pipe with Hot Air, Kind of like a Mini Storm going on in there.

Far as the Popping goes, You will always have some.

 

[micky nettle]

popping

Or in my case, finger loose de-compression valve. But in this case you will hear a ticking sound at top of cylinder head, thus sucking in air....Causing exhaust pop.