Red glowing muffler... is this right?

silverbear · #1 09-26-2009, 07:58 PM

I went for a bike ride this evening and noticed when I shut the motor down that the muffler was actually glowing red. I've not noticed this on any of my other bikes (although I don't do all theat much riding after dark) and am wondering if something is amiss with the motor or if there is an obstruction in the muffler maybe? The engine has about a hundred miles on it, an 80cc slant head automatic. It starts easily and runs well, has power. The engine did not seem excessively hot, no more than is normal at the end of a ride. I have noticed that this motor seems quieter than my others, with a little bit deeper tone. It is a chrome muffler and is turning blue about midway front to back. I think the vendor claimed it was catalytic, whatever that means with a HT kit. Any ideas? Should I be concerned? Thanks for any help. It is much appreciated. Mix is not rich... running Opti-2 at 100-1
Silverbear

EnFlaMEd · #2 09-26-2009, 10:13 PM

In car exhaust systems the catalytic converter will get extreamely hot. Ide say having a catalytic muffler is what is causing the glowing.

Kevlarr · #3 09-27-2009, 12:56 AM

Mine does the same thing and when I see pictures of other people's bikes I wonder how in the world are their mufflers all shiny when mine turned purple after the first ride.

bairdco · #4 09-27-2009, 01:26 AM

i haven't ridden at night yet, so i haven't noticed. but when i do, i guess i don't need to bring a cigarette lighter...

Venice Motor Bikes · #5 09-27-2009, 02:32 AM

If the pipe is turning that blue? it might be running a little lean.

silverbear · #6 09-27-2009, 05:53 AM

Thanks for the responses. I'll check the plug today to see what it looks like and try changing the notch on the carburetor needle. If glowing is normal, that's OK and the blue in the muffler I can live with, but don't want to wreck the motor.
Silverbear

Bikeguy Joe · #7 09-27-2009, 07:44 AM

I would say it's running on the lean side and the "cat" is obstructed. I haven't run one with the cat, but none of the ones that I've build have run that hot.

**2door** · #8 09-27-2009, 09:59 AM

Silver Bear,
The 'blueing' of chrome due to heat is normal under most circumstances. The quality of the chrome plating will effect how long it will take for the chrome to begin to show the heat effected area. With that said, I agree that you might be a bit on the lean side. Getting hot enough to actually glow is pretty darn hot and potentially dangerous. Check your plug and richen your mix just a little. I'm running Opti-2 also and have never experienced your problem.
Tom

Kevlarr · #9 09-27-2009, 10:18 AM

I opened up my cat muffler this morning and was kind of surprised at what I saw in the muffler end. The muffler is two baffles with two tubes going through both baffles and the outlet tube goes through the bottom baffle only. What surprised me was the two tubes that go up into the chamber between the muffler and the cat are completely crimped flat so the only exhaust that goes through has to go around the gaps in the welds and around the edge of the baffle. I ran a long flat blade up into the tubes and opened them up about halfway. Just went out for a test ride and there wasn't any difference in the noise level that I could tell but the idle jumped WAY up and I had to turn the idle screw out about halfway to get the motor to idle again.

One other thing, the worst area of "bluing" on my muffler is right in the middle, exactly where the tubes were crimped closed.

silverbear · #10 09-27-2009, 10:30 AM

Quote:

Originally Posted by 2door

Silver Bear,
The 'blueing' of chrome due to heat is normal under most circumstances. The quality of the chrome plating will effect how long it will take for the chrome to begin to show the heat effected area. With that said, I agree that you might be a bit on the lean side. Getting hot enough to actually glow is pretty darn hot and potentially dangerous. Check your plug and richen your mix just a little. I'm running Opti-2 also and have never experienced your problem.
Tom

I just took a look at the plug (cold engine and I did not shut it down from wide open throttle, etc. and then pedal home as is recommended) and if anything the plug is on the dark side. The clip was on the second notch from the top and I have just raised it to the top, which as I understand it should make it a bit richer, correct? I can't remember for sure. Danged brain injury does not help (lightning survivor).
Silverbear