Maybe this pipe is just strange to me, I dunno. I bought it off some guy on Ebay. Looked like he only had the one and it was priced pretty right.
When it showed up I noticed it had two screws that held the end cap on the muffler body. Naturally I had to take them out, pull the cap off and look inside. I found there was some sort of crude cat converter in there.
Just goes without saying, that had to come out. Probably violated a few Federal laws doing that. So I put the pipe back together without the cat conv. and put it on my HS 49cc 4G. The pipe that I did have on it looked about the same but the muffler was all welded together and no screws. I figure it has the same sort of cat in it but I can't get it out easily.
Anyway, I put the new pipe on not knowing what to expect. It really isn't any louder, it just has a different tone to it. Clearly, it's allowing more air to move out. On my test ride, I took the bike up a bunch of hills and it pulled them somewhat better than before. Seems to have lots better mid range torque.
I'll need to do a plug chop with it to see if I need to drill out the main jet a little more. Chances are it's running a bit lean right now.
I know there's lots of ways to reduce back pressure, but most of them also make a bunch of noise. Personally, I'd like to maintain my 'stealth' status.
Now maybe these pipes with screws are common as belly buttons, and maybe they're not. I don't know. But I do know now if you can get rid of that cat thing and still keep the muffler body intact, you're going to feel more power with your butt-dyno and still not wake the neighbors.
When it showed up I noticed it had two screws that held the end cap on the muffler body. Naturally I had to take them out, pull the cap off and look inside. I found there was some sort of crude cat converter in there.
Just goes without saying, that had to come out. Probably violated a few Federal laws doing that. So I put the pipe back together without the cat conv. and put it on my HS 49cc 4G. The pipe that I did have on it looked about the same but the muffler was all welded together and no screws. I figure it has the same sort of cat in it but I can't get it out easily.
Anyway, I put the new pipe on not knowing what to expect. It really isn't any louder, it just has a different tone to it. Clearly, it's allowing more air to move out. On my test ride, I took the bike up a bunch of hills and it pulled them somewhat better than before. Seems to have lots better mid range torque.
I'll need to do a plug chop with it to see if I need to drill out the main jet a little more. Chances are it's running a bit lean right now.
I know there's lots of ways to reduce back pressure, but most of them also make a bunch of noise. Personally, I'd like to maintain my 'stealth' status.
Now maybe these pipes with screws are common as belly buttons, and maybe they're not. I don't know. But I do know now if you can get rid of that cat thing and still keep the muffler body intact, you're going to feel more power with your butt-dyno and still not wake the neighbors.
