backfiring/popping

[Racer]

I bought a used 08 K9 EFI. The previous owner had installed 2-1 RB racing pipe. It runs good but if I am on it and let off the throttle it is popping. I don't think the pipe has any baffles and I don't even know if that pipe comes with baffles? I don't see any sign baffles where removed. Anyone familiar with these pipes? And is some popping normal?

 

[stlmikie]

A certain amount is somewhat normal. Rest assured the RB is the best or one of the best pipes performance wise you can have. As far as things you can do to fix the issue yourself. Not much. If there is a dyno tuning facility in your area you can take it to them to make sure your tune is proper. Unless you have the software to tune it yourself.

 

[KANSAS-K9]

my 08 k9 popped quite a bit i had the carb tweeked and reversion cones put on it, they mount between the heads and the pipes, i'm sure one of the gearheads on here can explaine the concept

 

[Racer]

A certain amount is somewhat normal. Rest assured the RB is the best or one of the best pipes performance wise you can have. As far as things you can do to fix the issue yourself. Not much. If there is a dyno tuning facility in your area you can take it to them to make sure your tune is proper. Unless you have the software to tune it yourself.

OK . Thanks. I am going to change the cam and install a tuneable VFI in the future. I will look into it more when I have software. Thanks.

 

[stlmikie]

Does it have the stock cam?

 

[Racer]

Does it have the stock cam?

As far as I know.

 

[Ratman]

Also check flange bolts that hold exhaust to heads. If not nice and snug you will get decel pop. Many have doubled up on the old style wire mesh type flat gaskets to prevent. Good luck and enjoy your bike!

 

[08mastiff]

Generally speaking the EFI's don't have the decel popping issue. My scoot has the V&H 2-2 and the only time it would decel pop is when I experimented with taking the baffles out. Sounded like shit so I cut them to 5" and put them back in. That stopped any decel pop. Not sure whether the 2-1 exhaust has baffles. I would guess that it should and if you don't see any in there that may be your reason for the decel popping. I would call V&H and find out before you spend money on a tuneable VFI.:zz2cents:

 

[Racer]

Also check flange bolts that hold exhaust to heads. If not nice and snug you will get decel pop. Many have doubled up on the old style wire mesh type flat gaskets to prevent. Good luck and enjoy your bike!

I will check that. I do know that when I got the bike the pipe on the rear cylinder was not very tight. Whoever installed it apparently tightened the pipe bracket before tightening the flange bolts. I found that and snugged them up but did not pull the pipes all the way off to check gaskets. I will buy some gaskets, pull the pipes and replace, and go from there. Thanks.

 

[Th3InfamousI]

I am pretty sure RB does not use baffles in any of their exhaust as they are 2-1. I wouldn't add any baffles/mess with the exhaust as this is hands down performance wise probably the best exhaust you can purchase.

From the website thought it was funny:

You don't make power by adding restrictions to your exhaust system whether it's a bunch of stainless discs or some damn piece of aluminum billet machined into a Harley butt plug!

 

[erldawg]

OK . Thanks. I am going to change the cam and install a tuneable VFI in the future. I will look into it more when I have software. Thanks.

Look behind the little cover on the VFI/ECU to see what the connection looks like. If it's a nine point connector the ECU is the stock one. If it's a mini USB the module has already been changed and you have the ability to tune.

 

[X-ray Doc]

BR does make a baffled pipe, but it looks different than their pro-pipe, longer and the baffles are not removeable. The pro-pipe does not have baffles, so it is going to have some poping, go to their web site to see which one you have. Also, if the former owner spent money to get the BR, I would guess the cam has been changed also, I would check before buying another cam.

 

[Racer]

Look behind the little cover on the VFI/ECU to see what the connection looks like. If it's a nine point connector the ECU is the stock one. If it's a mini USB the module has already been changed and you have the ability to tune.

Just my luck, it has the nine pin connector.

 

[Racer]

BR does make a baffled pipe, but it looks different than their pro-pipe, longer and the baffles are not removeable. The pro-pipe does not have baffles, so it is going to have some poping, go to their web site to see which one you have. Also, if the former owner spent money to get the BR, I would guess the cam has been changed also, I would check before buying another cam.

Not sure about the cam. I do know now the S&S module is stock. Therefore, I am thinking it is probably the stock cam as well?

 

[1mndg]

More times than not, decel pop is caused by air getting into the exhaust from an air leak somewhere. Check for leaks in the intake and exhaust flanges and make sure all not used vacume ports on the intake are plugged. If the exhaust is not tight and sucking air, try a set of Screamin Eagle exhaust gaskets. Found them to be one of the best. Hope this helps.

 

[erldawg]

Do you have the oxygen sensors installed on that RB 2-1 pipe?

 

[Husker-Wolf]

If installed correctly, the RB pipe will have their CNC machined gaskets installed that need to be used with their pipes. You may get by with other gaskets, but it will probably cause problems with leakage.

 

[Racer]

Do you have the oxygen sensors installed on that RB 2-1 pipe?

Yes it does. I have not pulled the exhaust yet to look at gaskets. As Husker Wolf mentioned I don't think the RB pipe uses a mesh gasket. I am planning to install cam upgrade so I figured prior to that I contact RB and get new exhaust gaskets since I will be removing exhaust anyway.

 

[Racer]

BR does make a baffled pipe, but it looks different than their pro-pipe, longer and the baffles are not removeable. The pro-pipe does not have baffles, so it is going to have some poping, go to their web site to see which one you have. Also, if the former owner spent money to get the BR, I would guess the cam has been changed also, I would check before buying another cam.

My pipe is the longer style however it does not have baffles. It does have the stock cam by the way.

 

[ksmike]

Do you haven any pics of your bike, on the exhaust side? I have been thinking about getting a RB pipe and curious how yours looks and how you like the sound?