Wrapping the Exhaust Pipe? Pros & Cons???

[AZRider]

I have an 04 CRF450 and was thinking of wrapping the Exhaust pipe. A few questions I have are:

1: What's the best stuff to use and where do you get it?

2: How much of the exhaust do you wrap?

3: Can you ever take it back off once it's been on?

4: What are all the pros and cons?

Thanks!!

?

[RMXC51]

From my hot rod days, I thought that header wrap was mainly used to hold heat inside the pipes on multi cylinder engines, especially header systems, to keep the gasses hot and help each cylinder scavenge the others. It wouldn't really help much on a single cylinder engine. I bet if there was any real advantage to using it on a bike, Windham, Preston, etc would be running it and there would be some visible header wrap sponsor in MX.

[ob1quixote]

www.designengineering.com has good wrap. Get the 1 inch, it warps tight to curves. Get the ties they sell too, they are top notch. The wrap has a center line for nice even overlaps.

I wrapped my XR400 back to the joint between the muffler and header pipe. Remove the header, it will make wrapping much easier!!

Yes, it will come back off.

Pro's: Heat does not radiate from the header back into the engine. Supposedly higher exhaust flow speeds, more power. My take, a cooler engine runs stronger and longer, and with out a doubt my bike runs cooler with the wrap!

Con's: Some folks say the extreme heat concentrated on the pipe will weaken it, or make it brittle. My wrap has been on for years with no header faults. Maybe they will "pipe up", they do have points to make.

But I will risk a relatively cheap header replacement than any heat-induced engine failure. Being a fat old slow guy, I dont get the airflow through the motor that others do!!!!

i have installed wrap on the '98 XR400, '02 XR100, and the '87 TRX250 ATV, which sees extreme duty when pulling sledges to groom trail, and when it is equipped with my "1-of-a-kind" backwoods tow truck hitch, which I use to tow broken motorcycle out of the woods at the Swamp Fox Enduro. At first, it was just wrapped, and I found that I could ride in short pants without "radiation burns". I have since added a cooling fan, and it will comfortably perform low speed trail duties all day.

And, after hard running, I can touch the wrapped pipe with a bare hand without losing skin.

Try that with an unwrapped pipe!!!

And should you wrap the pipe, the first run will burn off oil used in manufacturing. Get a picture, looks like you are laying down a smoke screen!!!

Robert ?

[TechGuy]

I purchased a bike that had a spare exhaust with the tape on it. It looked like S#!T, and was basically permanent. I just threw it in the garbage. Don't do it. ?

I really don't have any strong opinions though. Can you guess which bike this came with?

[Dieselchild]

You can wrap a stainless or regular steel header but do not wrap a Titanium exhaust as it will turn to dust and broken pieces in a mattrer of a few rides/races. It will make your bike run cooler and makes more hp supposedly.

[ob1quixote]

Go to "One ATV cycle riders love" in the general forum for a picture of wrapped pipes, and my ATV tow truck.

Sorry, there wasnt a KTM around!!

Robert ?

[Fastest1]

I have run it on street and roadrace bikes with no problems whatsoever. It does keep the heat in the pipe. It will stop that burnning of your pants if that is a problem for you. It comes off fine, just unwrap. It think whoever posted he had to throw the header away wasnt using Thermotech. I polish my pipes anyway so it doesnt matter to me. It will disintegrate during repeated high pressure washings but only after a year or more. It is like 20.00 bucks do it. ?

[qadsan]

There are benefits to wrapping the header pipe, but one of my worries with wraps is mainly with 'plain carbon steels' which can actually suffer from thermal fatigue, temper embrittlement, and accelerated corrosion. Thermal fatigue is just the process of cyclic heating and cooling. This is common to all exhaust systems, but the thermal wrap exaggerates the problem because the temperature that the exhaust material is subjected to is higher than it would be without the wrap and 'some' materials will be more subject to this than others. The heat that is normally dissipated throughout the engine compartment is held in the exhaust, causing it to be heated to temperatures where corrosion is accelerated, and thermal fatigue is greater due to larger gradients in the heating/cooling cycle. Holding carbon steels in temperature ranges which can be sufficient to cause a phase change in the steel causes temper embrittlement (AKA re-crystallization) and causes normally ductile steels to become brittle and fail in a brittle manner. The end result is a combination of these phenomena, which results in brittle cracked parts with high levels of corrosion. Imagine how you'd feel wearing a full length coat in the heat of an Arizona/Nevada summer! In short, the heat wrap will keep the heat off your leg, but possibly at the cost of shortened life on 'some' materials. I'd also like to point out that its not uncommon for dealers or exhaust manufacturers of automobiles (JB Headers, Thorley, Gibson, Crower, Rodworks, Edelbrock, etc) to void your warranty if your headers are wrapped and that's something else you may want to consider in addition to any benefits, but a header pipe for our bikes is cheap and simple to replace compared to other applications. I don't know the official position of any motorcycle pipe manufacturers, but I'm sure some will take a dim view of this when it comes to any warranty issues. Just more food for thought, but also take a look at coatings cause they also offer benefits and generally look nicer, but they are also more expensive as well.

[skip #7]

My 02 CRF has been wrapped since I bought it in nov 01 ,Had no problems keeping the heat in helped the low end the 02 had problems with low end also you don't get the dings from rocks hitting the cherry red hot pipe.scott summers at summers racing is where mine came from was like 25 bucks, you soak it in water then wrap the pipe, start it and cook it the remove the pipe again and paint the wrap with heat paint to seal it then fire it up again and cook it again the your done.