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Swivel
2nd August 2016, 22:55
Just a quick question. What is the purpose of wraping tape around header pipes.
Cheers.

Virago
2nd August 2016, 23:14
It doubles the value of cafe racers.

neels
2nd August 2016, 23:17
It keeps the moisture in after you've ridden the bike in the rain, to make the headers rust faster.

Akzle
3rd August 2016, 06:59
it gives you +10 hp

jellywrestler
3rd August 2016, 11:02
Just a quick question. What is the purpose of wraping tape around header pipes.
Cheers.

same as putting a rubber on your cock, it stops you spreading your manhood....,

old slider
3rd August 2016, 12:20
same as putting a rubber on your cock, it stops you spreading your manhood....,


Bwahaha, Note to myself, be very careful on the questions you ask.

I just learnt so much from this Q. obviously wraps are only meant for our hands, unless bare knuckle fighting, lol

skippa1
3rd August 2016, 12:31
Just a quick question. What is the purpose of wraping tape around header pipes.
Cheers.
I brought a Buell that had it on the headers, unwrapped them to find damage on them that the wrap covered. Re wrapped them cause didnt want to fork out for new pipes, or others to think i had done the damage. It was a pain in the arse, it would soak up the rain then steam like buggery at the traffic lights, looked like it was on fire lol

OddDuck
3rd August 2016, 12:35
Insulates the headers, keeps the exhaust hot so it's less dense than a cooled exhaust gas flow. This means that the engine is pumping less mass so breathes easier. Performance gain.

Problems:

May affect mixture causing lean-outs and serious engine damage

Traps water and humidity, accelerates corrosion

Raises header operating temperature, accelerates corrosion

Basically it's a (initially) cheap, low-tech, low difficulty way to get a moderate performance gain. On a racebike, why not. On a streetbike, look forward to replacing headers at low mileages / time intervals.

It's over-used for the look by would-be custom builders and now has associations with cheap, shoddy work, on bikes that weren't worth rebuilding.

AllanB
3rd August 2016, 18:44
It is actually a very functional product - when you fall off your hero equipped CB400 cafe racer with crappy antique tyres, upside-down handlebars, no fender and slammed suspension, you will then use the exhaust wrap as a bandage to stop your hipster jeaned and no gloved body from bleeding out.

Crasherfromwayback
3rd August 2016, 18:49
It actually works a treat on bikes that need any lil gains you can get. When doing my 883 Twin Sport race bike on WMCC's dyno, we found we could move the max torque higher or lower in the rev range depending on how long we went down the headers with it. I was very surprised. But for the wank value of it on the heaps of shit everyone is putting it on...it's just that.

Big Dog
3rd August 2016, 18:59
According to a documentary I watched a decade or so ago it was originally to keep the heat in the pipe rather than in the engine bay and therefore out of the cabin of hotrod cats before air con was a thing.

Sent from Tapatalk. DYAC

Drew
3rd August 2016, 19:01
It looks cool sometimes. Looks bad ass on a set of V8 headers.

bogan
3rd August 2016, 19:08
Chances are if you're not running to the ragged edge of performance or designing your own pipe, or working with someone who is; it'll be of two uses: Looks, and heat insulation to keep heat away from other bits.


Insulates the headers, keeps the exhaust hot so it's less dense than a cooled exhaust gas flow. This means that the engine is pumping less mass so breathes easier. Performance gain..

Less dense yes, but the engine still pumps the same mass. How they work is by maintaining gas velocity, creating more predictable and less chaotic wave effects, allowing pipe tuners to design exhaust systems for best effect. Best effect being that the engine pulls in more mass, to make more power with.

AllanB
3rd August 2016, 19:27
It looks cool sometimes. Looks bad ass on a set of V8 headers.

Matter of opinion I guess. I don't like the look - I understand the original intent of the product for racing. But visually there is nothing hornier than a beautiful curved set of naked headers snaking their way in stainless, steel or titanium glory down a engine.

husaberg
3rd August 2016, 19:40
Insulates the headers, keeps the exhaust hot so it's less dense than a cooled exhaust gas flow. This means that the engine is pumping less mass so breathes easier. Performance gain.

Problems:

May affect mixture causing lean-outs and serious engine damage

Traps water and humidity, accelerates corrosion

Raises header operating temperature, accelerates corrosion

Basically it's a (initially) cheap, low-tech, low difficulty way to get a moderate performance gain. On a racebike, why not. On a streetbike, look forward to replacing headers at low mileages / time intervals.

It's over-used for the look by would-be custom builders and now has associations with cheap, shoddy work, on bikes that weren't worth rebuilding.


According to a documentary I watched a decade or so ago it was originally to keep the heat in the pipe rather than in the engine bay and therefore out of the cabin of hotrod cats before air con was a thing.

Sent from Tapatalk. DYAC

The original reason it was used in Nascars was to keep the exhaust heat from cooking alternators.
Any performance gains are from not having the correct length pipes in the first place.
That said Aprilias and other GP bikes did have carbon fibre shrouds to keep the 200KM+ breeze from cooling the pipe to much (2 strokes when at high revs you want them hotter for more potential over rev.)
but the main reason they were used (along with water colled crankcases was to stop the pipes heating up the crankcase and therefor the intake charge
Note There was also a heat reflective tape (like tin foil) that was I believe used to protect the fairing.


"Is there still a place for them?" I should think so; look at the Aprilia RSA125. There the cover does two things: shield the pipe from a cold air stream, but more importantly, as you can tell by the shield covering only the top half of the pipe: shield the crankcase from radiated pipe heat.
How much difference? We can only guess (which I avoid as much as possible) because nobody ever took the trouble of measuring the difference on a real track (were measuring the power would not be simple anyhow). The crankcase-shielding will give more power everywhere and the pipe-heat conservation will give more overrun which is extremely import for lap times.

All photos from Frits Overmars
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scumdog
3rd August 2016, 20:36
It looks cool sometimes. Looks bad ass on a set of V8 headers.


And covers bad welds...

Drew
3rd August 2016, 20:49
And covers bad welds...

When it looks good, the welds would too. It's a painful process to do a nice job on a set of headers, from what I have seen.

Swivel
4th August 2016, 03:43
Bwahaha, Note to myself, be very careful on the questions you ask.

I just learnt so much from this Q. obviously wraps are only meant for our hands, unless bare knuckle fighting, lol

Its a question no one wants to ask but everyone wants to know.

skippa1
4th August 2016, 18:31
When it looks good, the welds would too. It's a painful process to do a nice job on a set of headers, from what I have seen.
Fucken A

easy to rip off, fucken hard to get back on.