NZSpokes

Is there a performance benefit to wrapping the header pipes?

smokinjoe73

Only in mythology. I had mine wrapped to keep hot air off me but was told by a mechanic/tuner buddy that it raises combustion chamber temps so removed it.

CrickiKaze

I have never heard it raise combustion chamber temps, it supposed to insulate and increase exhaust velocity a little. Even if it did raise combustion temps then it shouldn't be an issue if your cooling system is up to par.

smokinjoe73

Oh, and your pipes and exhaust will fail much earlier due to way higher temps and moisture.

The pipes draw a lot of heat away from the exhaust manifold on the engine, but dont with wrap.

jedrek750

Visual effect?

smokinjoe73

Yes visual/make you feel badass/poser/wannabe is the very best use for it. It works awesome for that. It matches flashing leds, spiked bolts and bar-ends, neon windscreens and race slicks that will never heat up on the street.

E.Marquez

Wrapping the header has a very real effect. Not claiming engine performance.. BUT

My shock stays cooler. (Measured with an IR temp gun)
My motor temps are lower. (measured with thermocouple at spark plug base and header, plus coolant )
The heat radiating from the lower half of the bike at a stop in Texas summer heat is less. (observed "felt" difference)
My lower faring no longer gets heat damaged. (observed)

So while I wont make any claims of better exhaust gas scavenging... or any such thing.. I can say my pipes are not rioting like some claim will happen... and I don't have any feelings of badassness by having ugly wrap on my hearders... It looks like crap, but really does work for what i want it to do, with no observed ill effects.

smokinjoe73

To each his own but how could motor temps be lowered by raising header and exhaust temps?

Maybe optimistic observation possibly? The headers truly dissipate heat from the head into the atmosphere. When insulated they dont.

So for sure you are more comfortable but at the bikes expense. (no motore benefits from more heat). You are losing the heat sink properties of the headers, which is substantial.

But yeah, no melted plastic or legs I agree.

NZSpokes

Not after feelings of badness more feelings of coolness.

As in me legs get hot commuting on the bike. Was just wondering if it made a difference to tune on the bike.

Back in my 250 days I had a bike called a Haonda CBX250rs. I wrapped the headers on it and it ran lean. Went up a jet size and found some power. But it may have just worked for that bike.

E.Marquez

You no longer have super heated tubes next to what is a lower temp heat sink (the motor) is the best educated guess I can make on what allows the lower engine temps post header wrapping.


So while I wont call it scientific proof. My digital meters, data logging give me enough evidence to support what I believe to be true..

Love to have you do some temp data logging of exhaust gasses, head temps, coolant temps and show me where my observations are incorrect or "overly optimistic"

Im always up for learning new stuff...would be great to have someone else check temps and confirm or deny what i found .
bottom line, I've measured with digital temp meters and it supports what Im saying.

E.Marquez

I feel pretty sure you're off base with that assumption .... but to each his own.

Ive measured HP, temps and such and it supports what I have stated.

You say otherwise and Im fine with that,,just curious why you think that?> what have you tested, measured, observed?

Thanks

E.Marquez

Joe... you mentioned Combustion temps being higher as told to you by a mechanic friend..???

Perhaps i missed something..
I used an under sparkplug style thermocouple to read head temps....and K type thermocouple on the header.

I wonder if that is not an accurate way to estimate changes in "combustion chamber" temps?
Never did I read a HIGHER temp of those two points after wrapping the headers... So concluded if the head and exhaust gasses were not hotter post wrapping, the combustion chamber was not hotter....

Thoughts?

NZSpokes

Thats a very fair point. I come from 919s and its common to wrap the exhaust where it goes past the shock on them as they over heat the shocks quickly as it is.

Do you remove the pipes to fit the wrap? Seems it would be very hard to do on the bike.

E.Marquez

Yes I had to remove both headers

VTR1000F

Thanks for the shopping list, joe.

CrickiKaze

There is a lot more proof stating the usefulness of wraps (when done properly) then this so called poser/badass effect and again I have never heard such a claim of it raising combustion chamber temps. If you are not allowing the heat to radiate through the pipes its going out the exhaust and as I stated you may see a higher exhaust velocity(may not see it in this motor now that I think about it).
I have seen both claims of the piping rusting to hell and piping remaining just fine and the difference was wrapping it properly and using the recommended coating on the wrap and whatever else is needed.
If that is not up to your liking than having the pipes properly ceramic coated is the better option, no added weight if any and all the benefits of the wrap with out the bulge/tacky look as well as no concern of corrosion.

mikstr

well, Roger Ditchfield said that they gained up to 4 hp when they wrapped the pipes (full wrapping from ports all the way back to link pipes) on their racing VTRs some years ago. Do a search on the vtr1000.org site, he posted it a few months back..... I, too, was sceptic, but as Roger actually did some development work on this very subject (with dyno runs to prove) I am now a believer. Granted, not sure how much gain would be on a less modified mill, but I certainly can't see it causing a hp loss....

8541Hawk

Damn Micky you ruined all the fun..... It has been interesting hearing the guessing that has been going on but yeah there have been proven gains....

Though with my carbon cans, I will pass as it isn't worth the effort for me.

mikstr

sorry Mike, I have little use for the urban legend face-off....

7moore7

Ok but where's the data on bacon wrapped headers?

8541Hawk

In my belly.......

smokinjoe73

For me the extra heat and shortened pipe life isnt worth it. And as was stated, if you wrap them for horsepower it would only be in conjunction with carb jetting.

Maybe fine for a racebike but I wouldn't want that trade off on the street. (I ride every day)

And the wrap does hold moisture so deterioration seems to be an issue. As well as metal rarely lasts longer or better when heat cycles are more extreme.

Here is another opinion on the subject Exhaust Header Heat Wraps - Do Not Use.

I had mine wrapped for a while, my theory being that the radiators and oil cooler would have better air to breathe in 100* heat.

I really want to use it, just been told by every bike mechanic (race guys not squids) that you trade longevity.

I guess if I had an extra set of pipes as spares but my carbon 2 bros cans would not live long either and thats too rich for my blood.

Not to mention (or maybe I did) that I cant (wont) afford downtime to change an entire exhaust system.

The wrap for sure holds moisture after a rain rides.

And for sure, gains on racebikes is just not always gains on street bikes.

E.Marquez

Mike

Who was guessing?

skokievtr

I think the heat insulating effect at the shock and front of the motor is worth it, and have not seen pipe corrosion in 4 years. I do need to recoat the warp though. My unscientific measurements did also show a benefit.

smokinjoe73

Skokie, what was the benefit?

skokievtr

As I said, keeping some heat off the shock and front of the motor and oil filter. I also fabricated an oil filter heat shield (see photos).

Everything positive stated in this thread and what I've read related to the + & - of header wrapping still leads me to believe the positives out way potential negative results.

MOONSTER

Well, i guess i'll throw my 2 cents in. i have had my pipes wrapped for over 10 yrs. now, & recently unwrapped them, to put new wrap on. my pipes, looked exactly the way they did 10 yrs. ago. I would imagine, keeping the wrap painted with a good high temp paint, that would keep them sealed, would help prevent moisture getting to the metal.

The main reason i performed this, was to help take some of the radiant heat from the pipes away from the engine, & rear shock. I have worked in the industrial generator field for over 30 yrs., & we insulate diesel engine exhaust with thermo blankets/covers to help keep the internal exhaust temps higher. This does help with the scavinging of the exhuast gases.

Do not think this would cause the engine internal temps to rise, if the hot gases are removed faster.

Included a couple of pics of my pipes.

smokinjoe73

AHAA! Moonster, THAT is the kind of evidence I was hoping for. Thankfully I still have half a big roll of wrap left.

I mostly want to keep heat off the oil cooler and filter (I have an aluminum heat sink can cooler on the filter).

Now where can I get some spiked bolts and mohawk hair for my helmet?