exhaust pipes

This is my first forum post, so I apologize in advance if I violate any guidelines that I am unaware of. That being said, I ride a single cylinder Buell Blast motorcycle, so the only one exhaust has broken off during a ride. While I was riding on the interstate going 70, I noticed that the sound...

So i'm getting my first bike from my girlfriends brother. it's a 1978 suzuki gs550. he told me that the guy he got it from cut off the exhaust pipes and gave it straight pipes. so i need to replace the muffler on it. i found a used set on craigslist, but it is for the 1980-1981 model. does...