glowing exhaust pipe,FSE 450

houndog

New member
Well, She's been fine as far as I know since the plug died. It's been very cold and I'd not started her for a week at least. So I go out there and it is a no go.

Spits, sluggish.....battery goes limp. So I let her sit a little while and jump her off with the Jeep. She fires right up. I let her idle a few minutes and notice the exhaust pipe is cherry red!!!!!! I shut her right off. Wait a few minutes and start her up and ride down the road....it's like 36 degrees. Within a 1/2 mile it's starting to glow. I head back in the drive and shut her off.

She seemed to be running fine.

Any suggestions would be very nice!
Ed
 
Okay so red hot means running very lean. Check for air leaks around the boots of the fuel injection. It's an 05 FSE so that means it should have the yellow and blue wire for emissions control, try running with the wires in the opposite configuration (you're probably running on the lean map). I'm pretty sure you need to remove the cap on the end of the plug otherwise it'll work, yet it'll have a spark gap and can cause it to run weird.
 
Does your local fuel have a lot of ethanol in it? I had a similar problem with ethanol fuel going bad very quickly.
 
Thanks guys! Please keep in mind, the thing has ~5k miles on it and I got it new. It had just been on the showroom floor! I've had few issues....mostly it goes 1K miles on a plug!

The wires are disconnected as they always have been. I am not opposed to trying the other way but the bike has always been perfect as it is.

MF, Hmmmm on the plug tip....I did replace the "emergency "B" plug" but am pretty sure I did not remove the tip on the new OEM type. The coil appeared to fit well but I just went outside and found the plug that went south, right where I left it, in disgust, on the ground in front of the shop :).....no tip on the end! Arrrgghhhhh.
I'll investigate this tomorrow fully! Thanks for the info!

Schlitzy, I am very lucky, I can get 93 octane ethanol free. I paid 3.19 today.
I test each batch to make sure it really is ethanol free. It is Gulf gasoline no less!

Thanks again fellas and please, any and all info, hints, suggestions or thoughts are most welcome!
Ed
edit.....Is it not possible it is running very rich and the extra fuel is causing the heat? Either way, it seems to run fine.....?
 
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Thanks guys! Please keep in mind, the thing has ~5k miles on it and I got it new. It had just been on the showroom floor! I've had few issues....mostly it goes 1K miles on a plug!

The wires are disconnected as they always have been. I am not opposed to trying the other way but the bike has always been perfect as it is.

MF, Hmmmm on the plug tip....I did replace the "emergency "B" plug" but am pretty sure I did not remove the tip on the new OEM type. The coil appeared to fit well but I just went outside and found the plug that went south, right where I left it, in disgust, on the ground in front of the shop :).....no tip on the end! Arrrgghhhhh.
I'll investigate this tomorrow fully! Thanks for the info!

Schlitzy, I am very lucky, I can get 93 octane ethanol free. I paid 3.19 today.
I test each batch to make sure it really is ethanol free. It is Gulf gasoline no less!

Thanks again fellas and please, any and all info, hints, suggestions or thoughts are most welcome!
Ed
edit.....Is it not possible it is running very rich and the extra fuel is causing the heat? Either way, it seems to run fine.....?

Yeah I know what you mean about the fuel and your exhaust temperatures, logic would dictate that more fuel = hotter but in reality the leaner it's running the hotter it'll run. Timing also comes into play, and also how close you aret o running at peak egt. Basically lean = hot :)

If the plug end does not fix it make sure the black wire is still ground and the yellow is not (when yellow is ground the bike is in 'lean' mapping). Next I'd say try spraying a little bit of CRC or something around the intake boot see if the idle fluctuates, if so you have a leak. Also clean your Inlet Air Temp sensor in the air box above the filter that can cause issues if dirty.
 
MF, thanks again. I have, in the past, had considerable experience with carbs. Not so much with fuel injection. I could rebuild a Weber in my sleep.

I've built a couple engines in my kitchen! My Formula Ford motor turned 9200 RPM! It was push rod motor!!! It had dual Weber side drafts (DCOE 40's) with velocity stacks. I never expected that engine to go 50K It did not. it went 180K, was still strong when I sold it!..........and NEVER had an air cleaner on it! 0-60 in my Siesta was about 6 seconds.....this was in the late 80's.....pretty quick back then.

I mention it because the only time I have ever seen a pipe turn red was on that car and it was in fact due to float sticking and it was dumping fuel into the intake.

I'm with you, it does "seem" lean ........I'll look for a leak but I'm pretty sure that is not the case. I also will check out the temp sensor and that plug tip.

I know the map wires are not hooked but I'll hook them and see what happens.

Thanks again, and please, all suggestions are welcome!
Ed
 
In my experience, a rich condition will cause the exhaust to glow red. This is from the excessive fuel burning in the exhaust.
A misfiring will definitely cause a rich condition.
 
Well, the plug requires the tip. Nothing has changed in the map wiring. Air filter looks good.....at this point I conclude I am screwed. After 3 min. putting and "gittin' it" around the yard the pipe is cherry red. She seems to run normally.......

Any and everything is appreciated in the way of suggestions and help!
Ed
 
It really sounds lean. If it was rich enough to make the pipe glow it wouldn't run very good. A lean condition and they will run good! Since it is FI I would check for air leaked in any of the boots from the throttle body forward. Also check the mass air sensor. Unplug it while the bike is running and see what it does. I had a Yamaha raptor that had a bad o-ring on the fuel injector and it ran lean and made the head pipes glow bright red. Also pull the plug and have a look. Is it white (lean) or is it black (rich)? Is it possible the muffler is plugged up with something (mouse nest, rag, etc)? Also I had an old cr125 that would just die and then fire right back up like you experienced, ended up being the CDI. I don't know much about gasgas 4T's but are the EFI and ignition controlled by the same unit? Could it be that is going bad?
I know my post is kind of random but just trying to throw out some ideas and food for thought.


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Yeah. If the plug tip is melting, the engine is detonating really bad.

I don't think there's a MAD sensor on the bike. It would compensate for the vacuum leaks.
 
Thanks again guys! Will pull and look at plug tomorrow. At least then we should know if it's rich or lean. BTW....the plug that died a little while ago looked "text book perfect"....just was "dead"....like an internal short.

One other thing....I noticed this at deep dusk. Today in the sunlight I could not tell it was glowing....but I did not run it that long. It was overcast and as the sun set it was obvious. I do not think it possible that I never noticed this in several years and I've ridden at night many, many times.

More after I pull the plug!
Ed
 
ok, have not had time to pull the plug. What I did do was go get some Techron fuel injector cleaner and dump a couple ounces in her. I started her up and she idled fine as always. I rode around the yard and she cut off. Would not start back up. I put the battery charger on and waited about 1/2 hour. Hit the button and she fired right up. After about 45 seconds to a minute the exhaust note changed noticeably. I took her out and up and down the road and everything seems back to normal! WTF?

So, I'll report back as things develop. The exhaust pipe was not glowing and she ran fine during the test ride.

Thanks for the suggestions guys and please, all thoughts are most welcome!
Ed
 
Update....still not pulled the plug. I've ridden her around a couple 6-10 mile trips with no issues. I think I've fixed it by not riding her in the dusk. Can't see it in the daytime.

Seriously, my buddy who is a Triumph mechanic at a dealership (where I got her) said it's probably ok and I never noticed it before. He also said that if I bring her down he'll look at the exhaust temp. He said "it could be as high as 1250 degrees (I think) and he'd expect that thin pipe to glow in the dark.

I'll pull the plug when I get a chance.
Ed
 
Hey Nick, thanks! I am sorry it took so long to see your reply. Been busy and have not checked back in. I appreciate you taking the time to ease my mind. She has been running fine. I got paranoid when she killed the plug and then when I replaced it I noticed the pipe glowing *^&*%^*&^(%^$......it was at deep dusk....

Ed
 
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