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Discussion Starter #1
I've been going back and forth about exhaust wrap in my head for a long time now - the pro's, the con's, etc. Is the look worth the potential damage to the pipes? Will I still burn the pinata out of my leg? Should I put $50 into wrap when I can put $25 into sanding and painting?

All my questions did bring up something I could not find a solid answer to though - I know that wrap will increase the heat inside the pipe, and therefore increase the scavenging effect and speed up the exhaust flow. Will this inevitably lead to a lean situation? In theory, since I'd be "increasing" the effectiveness of the exhaust, it should lean out the mixture right?

Honestly at this point I'm a bigger fan of EFI, but if I can ever nail this carb thing I might be more amicable to them.
 

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Discussion Starter #2
I should also add that I'm thinking of cutting the pipes shorter too - I've got the V&H Longshots and they are a bit long for me... that isn't going to affect the AF mix is it? I've never heard of it doing that but figured I'd ask the experts.
 

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I like wrapped pipes, it definitely helps with heat but will still burn you. Only time it has burned me was because I didn’t realize my pant leg was touching it at a read light and when I took of the hot spot on my jeans then touched my leg. Never got hot enough to melt anything tho. If you do wrap start the wrap at the end and work your way towards the flange. I do this so the wind doesn’t grab the overlay of the wrap. I have worn out a few wraps just by the wind damage to wrapping it backwards




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Discussion Starter #4
Thanks for the input - I really like the look too, even when the black fades out a bit, I think it looks even better... Just my style though, I like stuff worn in, like knurled anodized aluminum that has worn down a bit.

I'm just concerned that by adding the wrap, I'll be creating a potentially leaner situation than just leaving the pipes as is or painting due to the added scavenging effect.
 

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I should also add that I'm thinking of cutting the pipes shorter too - I've got the V&H Longshots and they are a bit long for me... that isn't going to affect the AF mix is it? I've never heard of it doing that but figured I'd ask the experts.
I too am interested in hearing if anyone has just cut their pipes shorter. I want some V&H short shots but can't get the wifey to okay the purchase. In the process of wrapping the pipes but still don't like the length of my stock pipes.
 

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I too am interested in hearing if anyone has just cut their pipes shorter. I want some V&H short shots but can't get the wifey to okay the purchase. In the process of wrapping the pipes but still don't like the length of my stock pipes.
Ask for "FORGIVENESS" not "Permission" hehe, I hear ya the cost of the pipes is a bit steep. I am trying to hide some cash here and there and hopefully will have a set soon.
 

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Ask for "FORGIVENESS" not "Permission" hehe, I hear ya the cost of the pipes is a bit steep. I am trying to hide some cash here and there and hopefully will have a set soon.
As an only child the forgiveness not permission is used a lot. Price of pipes isn't so bad but I hear that it is recommended to have a fuel thingy put on when installing the pipes I want. And that part is expensive.
 

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I've been going back and forth about exhaust wrap in my head for a long time now - the pro's, the con's, etc. Is the look worth the potential damage to the pipes? Will I still burn the pinata out of my leg? Should I put $50 into wrap when I can put $25 into sanding and painting?

All my questions did bring up something I could not find a solid answer to though - I know that wrap will increase the heat inside the pipe, and therefore increase the scavenging effect and speed up the exhaust flow. Will this inevitably lead to a lean situation? In theory, since I'd be "increasing" the effectiveness of the exhaust, it should lean out the mixture right?

Honestly at this point I'm a bigger fan of EFI, but if I can ever nail this carb thing I might be more amicable to them.

This is a first for me. How does increasing the temperature inside an exhaust pipe speed up the flow?
 

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This is a first for me. How does increasing the temperature inside an exhaust pipe speed up the flow?
I don't know if this works for exhaust systems or not, but I can see it being possible. I do know from some of my time working with certain engineers many years back that certain steam-powered machines used to add extra heat into the steam to give it extra energy - the extra heat allowing more work to be extracted from a given amount of steam. However that's under a highly pressurised system with much different dynamics to a bike's exhaust!

The wrap would cause the exhaust to run hotter, meaning the gasses do have extra energy available to them. But I personally expect that the increase in temp would be relatively small (20 degrees?) and with the rather open nature of an exhaust, I doubt it'd make much of a difference (without doing any real maths on the matter!).

I can also see outside air temperature differences having more of an effect - colder air means a greater volume of air is drawn into the cylinder. Vehicles have more power on a frosty winter morning than they do on a mid summer's afternoon, and I expect that'd have more of an effect than the wrap would.

But it is just after midnight here, and I've been rather busy today :)

I've love to know more on the matter myself.
 

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You don't want to add heat you want to keep heat in the exhaust.
Hot exhaust is less dense and less staple and moves right along if we keep it all the same temperature it is not running into a bunch of cooling, heavier exhaust gas further down the pipe.

Are you ever going to feel the performance difference in the seat of your pants.........no.
You may see it on the dynometer or in those few crucial inches at the finish line of a race.
Ceramic coating can do the same thing for more money.

Drawbacks to wrap:
It can make a slick, shiny looking bike look ratty.
If you live in a climate with dampness or salt atmosphere the pipes will rust out faster.
It doesn't work well with most heat shields.

Positives to wrap:
It can make your bike look ratty.
It covers up, ugly welds and rust.
The pipes don't have to look perfect to start with.

And the number 1 reason, it increases the time for a response when resting human meat against exhaust.
Exhaust pipe burns last well, in some cases last forever, roasting a pillion riders leg is really bad and if the word gets out there you are cooked.
 

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Discussion Starter #12
I’ve burned my ankle on a hot exhaust pipe before, so I’m not keen on ever having to do that again.

As far as heat making a difference in exhaust flow, it will most certainly. It’s like the difference between sucking a milkshake (cooler exhaust) through a straw (exhaust pipe) and sucking water (hotter exhaust). The less dense the medium (air, fluid, etc.) the easier it moves. The faster a medium moves, the more it tends to pick up more of that medium and push it along.

My main concern is damage to my existing system. I bought the bike with Vance & Hines longshots, so if I damage them in the long run I really won’t be out anything, but I would have damaged a $500+ set of pipes. And then I’ve got to replace them...
 

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So I wrapped both pipes. Besides looking better, imho, I have noticed a dramatic uptick in mileage. Before wrap I could go 108 miles before my low fuel light came on. Now I go an average of 149 miles with a high of 151 miles between fill ups.
 

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What would cause such an increase in MPG ???
 

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Discussion Starter #16
I am going to go out in a limb and say that some of the increase I’m MPG could be because of the added scavenging effect a hotter pipe has. I know the “performance” effects have been touted, and I generally agree - wrap is NOT going to give you a seat-of-the-pants hp increase - but, any change in the effectiveness of an engine is going to make the entire system more effective.

I can not believe that all the increase would be from that, but maybe some?
 

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I'm going out on the limb too, better be a thick one.
I'm not a fuel injection guy, but I kinda sorta think I know how some of it works, but don't know how much information the Phantom unit works with.
So I'm thinking, does the Phantom have an oxygen sensor that may be picking up a different sample now and therefore different output to the ICM/FI box?

The other thing I'd check is the spark plugs, if this thing has suddenly become more fuel efficient perhaps the spark plugs are looking excessively lean looking?

How far do other Phantoms go before the light comes on?
 

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I am wondering here how you can get a 30% increase of MPG from heat wrap only.
If so I want to get of that magical stuff for my old bike .


We were talking about FI bikes before and I thought they all had an 02 sensor. But found out only Calif bikes do. So there is that variable.
 

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I am wondering here how you can get a 30% increase of MPG from heat wrap only.
If so I want to get of that magical stuff for my old bike .


We were talking about FI bikes before and I thought they all had an 02 sensor. But found out only Calif bikes do. So there is that variable.

Actually, he said he got a 50% increase in MPG. From around 100 to around 150.
 

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That's even better yet! Where do I order those wraps???
 
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