Ok people it's been a Long time since I've kept up wth cycles. I noticed some bikes have a Kevlar or some kind of material wrap on there pipes. What are they and what purpose do they have.

 

Fiberglass. Keeps the headers warm to increase exhaust flow. I do it because I hated the look of my heat shields and didn't like the chrome. It was cheap and I liked them once they were on. Plus this keeps my legs more comfortable when stopped. It's mostly just a looks thing. The power increase is either null or unnoticeable. So don't do it for performance reasons.

 

Like Sawka said, for street bikes it's for looks and comfort. On racing machines, where a tenth of a horsepower and a hundredth of a second counts, it helps keep the exhaust gasses moving fast from when it leaves the exhaust port to the end of the pipe.

 

It helps promote rust and conceals the resulting cracks in your pipe.

 

^^^ Yep ^^^

 

I was wondering how long it was going to take before people decided to fear monger.

 

and now I know, thanks

 

Just because you don't believe it doesn't mean it doesn't ( and it does ) happen. Some oaf the wraps are VERY CORROSIVE when left wet

 

Ive also have had an exhaust crack that had never seen wrap. That topic has been discussed many time yet I digress. The question was "What are they and what purpose do they have?" Therefore you could give him a straight answer of the material and purpose or you could go on about hating on them. It's like when somebody asks how to deal with back pressure in their drag pipes and everyone tells them to throw them in the garbage and get a 2 into 1 because its oh so superior. Im sorry if I didn't find the comments all that constructive. We all have heard the stories from tony's brothers aunt that somebodies exhaust cracked with the wrap on it. Or we can give him the information he requested, suggest he does research, and make an informed decision. Oh wait this is a Harley forum. Informed decisions are not welcome. Just do what we all say.

 

That's it, no further discussion about wrapping pipes?