The EFI Harleys have what they call 'start-up fuel' when the engine is cold. The idea is to help bikes start when cold, kind of like an old mechanical choke. Until the engine reaches a certain temp the bike runs fairly rich. This situation in combination with the lack of flow through the cats creates the extra heat making the pipe glow; at least that is my theory and I am sticking to it!

With certain tuners (Direct link, TTS and the FP3) you can turn off the 'start-up fuel' at a much lower engine temp to help with this. Getting rid of the catted mufflers will help as well...

 

That makes sense. I need to look at them after I get home and see if they are glowing after a run.

 

Totally normal ,the pipe is thin idling no air going across the pipes plus dark area. My 4 stroke MX bikes would do this,does not take very long to start glowing. Easy fix ride it.


Keith

 

Cold start.....one minute idling......not normal

 

I work with steam at temperatures like that daily. If it is in normal daylight and like your second photo, that looks to be around 950 or so F. Yes, the first picture is alarming but I did notice the background was a bit dark. So also a yes for temperature. Looks to be around 950 F or so. But both these are on the OUTSIDE temperature. As thin as these new pipes are, probably not more than another 100 degrees or so to add to estimate the inside temperature.

It would worry me also, but with a bike under warranty, there is always the question if you would void warranty if you ditched the cat inside, or really did anything that takes it away from factory tune. Do you know how understanding HD is if you got a tuner and gave that bike a good tune? Same question with removal of the cat on the inside of the pipes, or if you got aftermarket pipes?

I guess for me these questions always pop up and it keeps me in the used market for things like this. I bought my first really showroom new car in 40 years two years ago. I am quite suspicious of these new bikes and cars with the needs for precise tuning to make sure they run right....

 

It's not to make them "run right." Thousands retune and they still "run right."

The problem is the stupid mpg and emissions requirements like California's that force them to do it.

 

That looks like a way lean running bike to me. Only time I have ever had a street bike with pipes that hot would be running lean, an intake leak(making it lean) or an exhaust leak.

 

No, it's not 900 degrees. About 517 was the hottest I recorded. Anyone else want to heat gun their stock pipes and compare? I'm willing to bet this is not an abnormal for stock.

 

Ddieselsmoke, I know it has been several years, and hope you are still on this forum to help me out (or perhaps someone else). Did you ever fix the issue with the glowing header? I have a 2006 Heritage Classic that is having the same issue with the rear header pipe. It gets glowing red hot at idle. When I first saw it about a year ago, my mechanic suggested a tuner, and he installed a Power Vision unit and he played around with and set it to run richer. I am not mentally capable to make any changes to the tuner. I last rode it last summer in So. California, and by the time I returned home after about a 40 mile ride, the bike was running extremely rough at idle, but after it cooled down, it ran okay.

It is an efi bike, all stock. I noticed a few days ago that the problem is still there. At idle, in my garage, at about 62 degrees inside, it began glowing after about two minutes. Numerous spark plug changes have no effect, but the rear plug indicates it is not running lean. I run regular grade gas. The header, as far as I know, is original equipment, but may be thin walled as mentioned here. This is not normal because I have a 2000 Heritage Softail and it does not do that.

P.S. I also found another of my posts, in 2016, in which I wrote about having this issue. Apparently it was never fixed and remains to this day, even with the tuner.

 

@carlmartine Send him a PM see if he's around.