Pipe Discoloration

[BIG--T]

will happen on most aftermarket pipes like my Cobras, but I'm looking at a Valkyrie with OEM exhausts headers that the are discolored. What would cause this? Burning too lean?

[JC]

Yep, too lean, or someone forgot to turn off the choke. Either way the EGT (exhaust gas temp)was too hot.

[old2soon]

I've also heard excessive idiling contributes to the exhaust pipes getting discolored. RIDE SAFE.

[BIG--T]

Thanks guys, I thought that was the major reason.

[MarkT]

Yep.  Comes from pipes too hot.  Caused by running bike badly out of tune (rich or lean), leaving choke on, or running the bike too long without moving air over the pipes.  i.e., running it in the garage every month in the winter w/o setting up a fan, rather than winterizing. OEM pipes won't color except the last inch next to the single wall junction, if you don't do these abuses.

[BIG--T]

Thx Mark, the IS I am looking at is very disclored at the headers and then where they go into big chrome pipe. I thought is was heat related. 

[valky1500]

Since Cobras are single walled chrome pipes there's no doubt they turn blue fast.

Using a Blue Polish rinses the blue away and turns them a more acceptable goldish.

[tonyfan70]

I have also heard that "rapping" the throttle excessively when the bike is cold will do this as well.

[BIG--T]

Since Cobras are single walled chrome pipes there's no doubt they turn blue fast.

Using a Blue Polish rinses the blue away and turns them a more acceptable goldish.

Yeah I knew about Cobras singled walled, I have them on my standard and are bluish but look great compared to this bike I'm looking at with OEMS.

[cookiedough]

bought my I/S stock OEM pipes and they were copper/goldish color pipes coming from the front as well with only 14K on bike 4 years ago.  Previous owner guessing ran choke way too long and/or bike out of tune pretty bad?  Really don't care too much since looks good enough and runs good enough for me.  I did use blue-away on the header pipes upfront with a cotton towel and rubbed the heck out of them for a few hours.  Did help say about 75% better, but still discoloration is present and can still be seen.  Blue-away did scratch the chrome up somewhat but not too bad.  I also used 0000 steel wool with the blue-away and that took even more coloration off the pipes.  Put some chrome polish on them to help shine them up a little afterwards, still not perfect, but good enough and can live with it.

[old grouch]

What would you say was the cause of the pipes bluing on one side only?   ???   2000 Std, one owner, low miles, (about 12000) bone stock.  Bluing occurred during first 1000 miles.  Lives in Kansas City.

[BIG--T]

What would you say was the cause of the pipes bluing on one side only?   ???   2000 Std, one owner, low miles, (about 12000) bone stock.  Bluing occurred during first 1000 miles.  Lives in Kansas City.

Do you have OEM or aftermarket?

[old grouch]

OEM. 

[Chattanooga Mark]

I bought my 99 Interstate with only 6500 miles on it and the header pipes were all very discolored. The bike was originally from Minnesota then Wisconsin before I brought it to Chicago. Likely too much choke. Guess I've just gotten used to it as it doesn't bother me anymore.

All the best,

Mark

[BIG--T]

I believe it was SmokinJoe that told me he painted his and I couldn't tell it. That would be the cheapest way out. I've heard you can buy a chrome piece that covers the header. 

[salty1]

Chrome-like ceramic coating looks good on headers and holds up pretty well. Check out the local powder coating facilities.

[larue]

i ve had cobra  6x6 on my tourer brand new for little over a year now, i put 8k on them and not one single bleuing mark.

[MarkT]

What would you say was the cause of the pipes bluing on one side only?   ???   2000 Std, one owner, low miles, (about 12000) bone stock.  Bluing occurred during first 1000 miles.  Lives in Kansas City.

I'm guessing right side, correct?

Choke linkage, sliding plate friction screws too tight.  Under the chrome cover.  Choke is pulled on by cable, pulled off by (weak) springs.  There are screws that hold the sliding plate down, and a nylon grommet that is supposed to attenuate the friction.  Get them too tight and the cable can pull the choke on but the springs can't pull it off.  The choke cable comes down to the left side, then on the other end (back) a cable goes across to the right side and piggybacks on the movement of the left side.  So if only one side has the choke stuck on, it has to be the right side.  I put graphite lube on mine where the friction is, and Loctite on those screws threads so they don't move. And added another spring.

[valky1500]

OEM pipes on the IS or any other Valkyrie DO NOT turn blue- EVER.

Because they are double walled. 

[salty1]

OEM pipes on the IS or any other Valkyrie DO NOT turn blue- EVER.

Because they are double walled.  

My bikes would not hold up under your comment (..."or any other valkyrie") and they both run extremely well!

[MarkT]

OEM pipes on the IS or any other Valkyrie DO NOT turn blue- EVER.

Because they are double walled.  

Yes of course you're right - I'm fulla crap. And so is everyone else who has observed their OEM headers with color.  BTW - there's a set on ebay right now, showing yellowing on the headers. Probably just the light, right?  I'm just guessing, I don't have the wealth of knowledge Valky1500 does, as I've only built 1200+ custom Valkyrie exhaust systems over 13 years from the double-wall OEM pipes.  The color I've seen on OEM double wall chrome headers, that was actually my rose-colored sunglasses, not the chrome with any color.

Got a good idea for ya V1500 - since your pipes don't color, feel free to idle your bike in the garage every month Dec-Apr for a half hour instead of winterizing, just so you can keep it ready to ride for nice days.

For those w/o V1500's expertise - don't forget and leave the choke on, don't run the bike badly out of tune rich or lean, and don't run the bike for extended periods without air moving over the headers, and your pipes shouldn't color.  Like these - a couple headers still in the shop, have like a dozen of these down in the metal pile which are worthless to me except for maybe art sculpture raw material.  Maybe v1500 would like to buy them since he can't see color...

[MarkT]

What would you say was the cause of the pipes bluing on one side only?   ???   2000 Std, one owner, low miles, (about 12000) bone stock.  Bluing occurred during first 1000 miles.  Lives in Kansas City.

I'm guessing right side, correct?

Choke linkage, sliding plate friction screws too tight.  Under the chrome cover.  Choke is pulled on by cable, pulled off by (weak) springs.  There are screws that hold the sliding plate down, and a nylon grommet that is supposed to attenuate the friction.  Get them too tight and the cable can pull the choke on but the springs can't pull it off.  The choke cable comes down to the left side, then on the other end (back) a cable goes across to the right side and piggybacks on the movement of the left side.  So if only one side has the choke stuck on, it has to be the right side.  I put graphite lube on mine where the friction is, and Loctite on those screws threads so they don't move. And added another spring.

I may have to go out and pull one to check but IIRC those screws that hold the grommets are a post screw with a set depth on them so they will not crush the grommet.

On my '98, they were impeding the movement of my choke slides.  As I said - added Loctite on the threads, reset them to low friction, and graphite on the nylon.  Stronger springs added just in case, and the problem has gone.

[valky1500]

All that I can see happening from leaving the choke on full is a set of ruined sparklers from an over rich fuel mixture and carboned up cylinders. When they get wet they are gone. That condition will not allow the plugs to fire very well and if at all. That's not to mention ending up with the gunked up carbs as another result.

Try as try may, even when the water temp is above 240* caused by over advancing the timing, and who knows where the oil temp would be then, it would only allow the plugs to clean themselves and the cylinders from carbon buildup. It will not allow a ruined set of plugs the repair themselves nor would it allow them to fire. If there is no fire then no heat to speak of now is there.

As a matter of fact, it's the spark plugs that go bad very easily and long before any damage can happen due to high of heat in an engine caused by the improper timing or carb settings. They are just like the fuses in an electric circuit that will pop when overloaded (overheated or wet) and will go bad long before anything serious like over heating will happen to your engine.

Don't get me wrong, I don't know everything. But there is only one way to discolor a set of double walled pipes and that's from a heat source coming from the outside.

Personally, I have never seen anyone take a blowtorch to a set of double walled pipes but that may have happened and many times before. 

[BIG--T]

MarkT, Thanks for posting the reasons for discoloring. I have a 98 STD that I bought that way at 8k and it ran great then and at 18k still does. It runs smooth and in warm weather it cranks without the choke after sittng for days. 

[old grouch]

MarkT--Thanks, I will have my KC friend check that out.  Would never have thought of that my own self.   ???   Stan