exhaust noise

[mickeyvex]

So I got a new set of custom pipes that I fabed up on my stock 1200. The dealership did a stage one upgrade on it when I bought it. The pipes are an inch and three quarter 2-2 system that are 38 inches long with big city thunder monster baffles installed. The bike runs great except for a fumbling bumbling sound that is most apparent in second gear at 3800 rpm and disappear at 4k. I can’t tell if this is a characteristic of the pipes or a jetting problem. Thanks for the help.

[Rico 05R]

How about some pics? We are picture whores around here.

[biknut]

More than likely reversion. I'm a big fan of Thunder Monsters, but they're not that good stopping reversion on 2:2 pipes that don't have a balance tube.

You can tune a lot of it out with a bunch of work, but it will still have a serious power dip between 3 and 4 k. When the reversion happens you go really rich.

[mickeyvex]

gonna have to post that tomorrow. no access to a camera right now

[Rico 05R]

I agree with Biknut, if you are only getting this symptom in a 200 rpm range, it is most likely reversion.

[mickeyvex]

thanks for the input guys. can reversion cause any damage?

[biknut]

thanks for the input guys. can reversion cause any damage?

I'm not going to say it can't cause damage, but I wouldn't be too concerned about it.

[mickeyvex]

I'm not going to say it can't cause damage, but I wouldn't be too concerned about it.

perfect. thats all i need to know. :D thanks

[wedge]

I agree, rich is usually very safe, it just costs HP.

[jharback]

Yeah, it's almost certainly a reversion problem. Highly unlikely to be a jetting problem.

[Big Al-1200c]

sounds like the jetting might need to be looked over. might be a little rich like some one else said.


More than likely reversion. I'm a big fan of Thunder Monsters, but they're not that good stopping reversion on 2:2 pipes that don't have a balance tube.

question: by balance tube, you are talking about the cross-over pipe?
I ask because I thought that the cross over pipe is what made 2-2 pipes, well 2-2, with out it you would have dual pipes?

[wedge]

sounds like the jetting might need to be looked over. might be a little rich like some one else said.




question: by balance tube, you are talking about the cross-over pipe?
I ask because I thought that the cross over pipe is what made a 2-2 pipes, well,,, 2-2, with out it you would have dual pipes?
Interesting, and logical fine tuning of termonology. Makes sense, but I have not heard that distinction before, I'm interested in hearing if this is correct.