Red glowing muffler... is this right?

[silverbear]

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]

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

 

[Kevlarr]

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]

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]

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

 

[silverbear]

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]

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]

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]

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]

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

 

[silverbear]

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.

Well now that's interesting. Are they supposed to be crimped like that? I'll see what effect my needle clip change makes and try that next if it doesn't improve. Did your muffler seem cooler? I know you can't tell about the golw until dark, but I realized later that my left ankle did feel pretty warm riding that bike.
Silverbear

 

[Kevlarr]

Well I just went on a 56 mile ride and I think it did make a difference. Best part was about 10 miles in my engine finally broke in and it was almost a religious experience. Everything smoothed out and I had waaaaaay more power. Easily cruised along at 28-29 and even set a new personal record, 34.5 mph!

 

[silverbear]

Well I just went on a 56 mile ride and I think it did make a difference. Best part was about 10 miles in my engine finally broke in and it was almost a religious experience. Everything smoothed out and I had waaaaaay more power. Easily cruised along at 28-29 and even set a new personal record, 34.5 mph!

Well, that's good to hear. About how many miles do you have on that engine?
I haven't had a chance to ride today due to persistent rain. Maybe tomorrow I can see if the needle change makes a difference.
I did however score a great find at the dump (transfer station) this afternoon. I always take at least something metal so that I have an excuse to visit the metal pile. At this particular transfer station I can take what I want and depositing metal is free. I always look for frames and wheels... the wheels are usually junk, but bicycle wheel means bicycle and it might turn out to be something. I've been on the lookout for a 20 bike so I can salvage the short pedal crank. Anyway I found a pre war Schwinn 26" man's bike. No head badge, but there is a Schwinn decal below the seat post and I recognized the pedal crank skip tooth sprocket. Nice old springer seat, not bad handlebars for a million years old and the frame and front fork are very good. Mangled rear fender and missing the front fender, wheels are missing. I can see a nice cruiser there with a new wheel set, new chrome fenders, stitch up the seat in harness leather. If it weren't raining I'd take a picture. I love shopping at the metal pile since the price is always right... free.
Silverbear

 

[Kevlarr]

Well with today's trip I have 384 miles on this thing.

Lucky you on the find! When I found my moped wheels at the scrapyard there was a 60's bike laying there too but unfortunately it'd been run over by a loader.

 

[silverbear]

Well with today's trip I have 384 miles on this thing.

Lucky you on the find! When I found my moped wheels at the scrapyard there was a 60's bike laying there too but unfortunately it'd been run over by a loader.

What oil are your running? Did you do a different oil mix for the break in?

In between rain drops I just took a picture... propped the front forks on a throw away rim. Paint isn't bad either for pre WWII. I have no idea what model that is, but probably a less expensive one. Still, it is a nice frame and fork. It will live again and in its next incarnation will go faster and give at least as much fun to someone as it did in it's first life. I feel no shame at all in transforming an old bike like this to a motorbicycle. It would cost way too much to fuss around finding original this and perfect that. I like bicycles to ride. Besides, I saved it from the crusher. I may paint it or leave it alone, maybe just touch up where it is scraped badly . I wish there was a way to know what year and model it is. I suppose there's a database for researching the serial numbers. Maybe "pre war cruiser" is good enough. I like the seat... wire wheel underneath and paint it black, add some foam cushioning and stitch it up in black harness leather. It will look good. I have too many projects, but something like stitching up the seat can be done sitting inside by the wood stove in January.
Silverbear
Silverbear

 

[Kevlarr]

Started out with the Wally-world cheap oil for the first two gallons then switched to Opti-2.

That is in really good shape, dare I say the paint looks nicer then your worksman! lol

Funny thing is your worksman can't more then 15 years old since the headbadge has their website on it.

 

[silverbear]

Started out with the Wally-world cheap oil for the first two gallons then switched to Opti-2.

That is in really good shape, dare I say the paint looks nicer then your worksman! lol

Funny thing is your worksman can't more then 15 years old since the headbadge has their website on it.

Yes, the paint, goose neck and handlebars are much better. It hadn't dawned on me that the head badge even had the website on it. You're right!
I've used the opti-2 since I first started it up. I should have paid attention to the odometer... not even a hundred miles yet.
Silverbear

 

[Bikeguy Joe]

Silverbear- moving the "C" clip up will result in a LEANER mixture.

 

[silverbear]

Silverbear- moving the "C" clip up will result in a LEANER mixture.

You know, that didn't seem right to me either, but I didn't trust my own judgment and searched out old posrts ro be sure. The one I read on the subject said up for richer, so I went with that. I'm glad it rained today and didn't have a chance to ride. Thank you for catching that!
Silverbear

 

[EnFlaMEd]

raising the clip lowers the needle thus leaning out your mixture.