Silencers change color where there is an internal restriction.

Clive W  

Doesn't a gold discoloration on the header pipe usuaully mean it is lean?  Blue means rich, I believe.  Maybe your pilot is too small...

Actually both indicate enough heat to discolor the chrome.  Gold/honey will happen first and then continue into blue with enough additional heat.  Some chrome is thinner than other chrome which will allow it to turn more easilt too.  In many instances, the excess heat is due to a lean condition.  I toyed with using a header wrap on mine at one point which helps to keep the heat inside the exhaust system.  In doing so, it blued my header greatly and began to blue my MAC where it had no discoloration before at all.  I've since removed the wrap and painted my header and muffler black.

I went back out and looked it over closer.  The gold color reaches just past the first bend, so it doesn't extend as far down the header pipe as I originally thought.

The gold color on the muffler is right at the heat shield, and I'm wondering if it developed because I didn't wipe the pipe down after installing/handling it before I started it the first time after installation?  The reason I wonder about that, is because it is just in one small spot on the muffler itself.  I think I can take some Blue Job I have and take care of that pretty easily.

So, all in all, I guess my discoloration isn't as bad as I originally thought, so all may be well after all.

Thanks for all the input though.

On a sidenote...  I went out for about an hours ride this morning in between thunderstorms, and I found a nice, straight, dry stretch of highway and opened it wide open.  First time I had done it since doing all the mods.  The Savage hit 98 mph in no time flat!!!  I could have probably coaxed a bit more out of it, but I was running out of straightaway and I found out what I really needed to know -- that I had plenty of reserve for passing if need be.  Plus, I had a bit of throttle left over, so I'd say 100 will be easily attainable (not that I need it)!

Probably the only other thing I intend to do soon is switch over to 20W-50 instead of the recommended 10W-40 oil.  I use Castrol GTX and it seems to do very well.

The stock header pipe is a double wall pipe, though not a very good one.  The inner pipe has only a 1.3" ID, which is very restrictive.  Anything that can be done which keeps the heat in the exhaust longer will aid in the exhaust scavenging effect...as in the use of header wrap, or ceramic coating, etc.

On the fuel octane issue, unless I misunderstand, the difference between the various octane levels is just the amount of anti-detonation additives which are placed in the fuel.   Why would that cause more carbon deposits with a higher octane fuel?

vroom1776 wrote on 12/31/69 at 16:00:03:



Both gold and blue mean to lean. The difference is by how much.  When the pipe runs a little hotter (slightly lean) it turns gold. If it runs excessively hot (extra lean) it starts to turn blue.

Interesting observation.  Where does one have to go to do a dyno test?  I'd love to find one around here and put the Savage on it just to see how close I actually am adjustment-wise.