Should i repack my pipe or leave it empty? sound vs loud

[Anonymous]

Hi there guys, I have a Kerker K45 4-1 and pipe, the muffler was beat to hell, the rivets came loose and hogged out the holes so we have to cut the main can down to drill new holes.

The can is about 3" shorter then stock, and fits the bike much better now too, it was longer then the back tire before!

The pipe had no packing in it at all, But sounded pretty good but loud before i took it apart.


I like a pretty loud bike!, but would the bike sound even better with some packing in it? Are some packing materials louder or sound better then then others? or should it leave this baby empty?


thanks for your help!
Jason

[Jethro]

Sound aside, the engine benifits from a little backpressure. One of the most common causes of burnt exhaust valves is usually a rotton exhaust.

[Katamaniac]

I've heard guys using Stainless Steel Wool for packing. If you can get ahols of first timer or Hoomgar, they are the guys that were talking about it, if I remember correctly.

[Anonymous]

Sound aside, the engine benifits from a little backpressure. One of the most common causes of burnt exhaust valves is usually a rotton exhaust.

While it is true that most engines will make more power with a bit of back pressure, an open pipe will NOT burn an exhaust valve. A lean condition will do that, not the pipe. If somebody burned a valve with a rotten pipe it was because they didn't recognize the problem and deal with it in time. If this bike is jetted for the empty can, it will be fine for a long time.

I like a pretty loud bike!, but would the bike sound even better with some packing in it?

That is a subjective thing. I do not like a really loud pipe (loud OK, not REALLY loud) and prefer the nice, mellow tone that comes from a packed can. That is me, your likes may be different. As long as your neighbors don't lynch you, the extra volume is not really an issue for the bike. It comes down to your preference and tolerance for noise.


Mark

[Anonymous]

I Just found some packing from a Brand new R1 can,in the shop here i guess i will use that, since its new and see how it sounds,

Now, 1 more question.. How much packing and how tight?

[Jethro]

While it is true that most engines will make more power with a bit of back pressure, an open pipe will NOT burn an exhaust valve. A lean condition will do that, not the pipe. If somebody burned a valve with a rotten pipe it was because they didn't recognize the problem and deal with it in time. If this bike is jetted for the empty can, it will be fine for a long time.

I always thought that a pipe with no backpressure heats up and burns the exhaust valves more than a correct exhaust due to excessive hot, spent gasses escaping through the valves than should be. Heard that from a mechanic, but those guys don't always know it all...