How much 1" exhaust wrap is needed for head pipe of chamber

[johnny248]

I was going to wrap my C16 head pipe up the point where the expansion chamber starts using 1" wrap. Is a 15' roll long enough for this? Or do I need to get a longer roll?

[motormike]

Opinion : 1 roll of 1 inch wrap will cover 18 inches of head pipe.
Buy two rolls, and if you don't use the second one, refund...

[Trafficjamz]

15' should be plenty

[Xxbeejay45xx]

Yes I have 5 ft on my arrow and 15' is plenty to finish.

[johnny248]

I ended up buying a 25' kit with clamps. I figure I'd rather have a little extra than not enough.

Thought I'd try out the newer Titanium LT wrap from DEI. It is supposed to last a little longer and is easier to install since the added flexibility lets you install it without soaking it in water first. I'm sure I'll post some pictures and whatnot once I get it on.

[johnny248]

Actually, I may have ordered the wrong stuff. I wanted 1" wrap. I figured it would work better with the smaller pipe, but I accidentally ordered 2". Do you think that will be OK? Or should I cancel it and get the 1" ?

All this being said, is it actually a good idea to wrap this? When reading about 2 stroke expansion chamber design, I read somewhere that it is very important to keep temperatures up in that header pipe that is before the expansion chamber. With the header pipe hot, it allows the exhaust waves to travel faster, and is ideal for the waves to reach the chamber. For instance, if the header pipe is too long, it doesn't allow for enough heat to build up and will actually hurt performance.

At the same time, I also read that you don't really want to use any wrap or any sort of thermal coating on the chamber because it can cause the design of the chamber to not function optimally for power.

So as I said before , my plan was to wrap from the flange up to the chamber extrance. Is this a good idea?

Lastly, I've read elsewhere that the exhaust wrap can actually cause pipes to crack or "shatter" for some reason also. It mentioned headers on race engines (car engines) and not specifically 2 stroke pipes.

[Xxbeejay45xx]

2" is fine. It's a bit wider for the curve of the pipe but should work if you over lap 1/2 of the width. I have read all about the cons of wrapping too. I have a Yamaha R1 and I wrapped my header all the way back to the cans and still have no problems with cracking. Maybe when you take off the wrap it will cause the metal to change color. I've heard don't wrap titanium it will brake the metal?? But I know for a fact that the wrap will change color if you don't seal it with silicon high heat paint. VHT flame proof paint that's what its called. I did a heavy coat on all my wrapped pipes. I Think its really for looks, helps with heat but maybe not by much. I haven't had any damaged pipes from wrapping.

[johnny248]

I guess I will see how the 2" looks when I try to wrap it.

I read about the titanium pipes also. Right on DEI's site it says not to wrap those. It is a good thing that I don't have a titanium pipe lol

As far as paitning or coating, DEI makes aa high temp silicone coating to apply to the wrap that is supposed to penetrate and protect the wrap so it lasts longer and doesn't deteriorate , but they say it is not recommended to use on their Titanium wrap. They say the titanium wrap already has a coating built into it which protects it and will allow it to last much longer than standard wraps. They also say it won't bond properly to the titanium wrap and therefore won't last. They do however say that you can apply it to steel pipes prior to using the titanium wrap to prevent rusting of the steel.

[Xxbeejay45xx]

Ahh there you have a titanium wrap as I use the cheaper white ones on eBay therefore I have to seal it with silicone heat spray. White turns brown really fast without any coating. And it will smell and burn a lot of smoke the first couple days.

[johnny248]

Yep, I decided to spend a couple more $ for the newer stuff. Just trying to decide now if I should paint the pipe with some HT paint, or that HT Silicone Coating before I wrap it.

We're you able to notice any difference in performance after using the wrap? Some people say that on a 2 stroke pipe you will be able to gain some performance, but also that the power range can sometimes be increased to a slightly higher rpm band because of the exhaust scavenging.