| Author | Message | ||
     Al_lighton |
I posted this elsewhere on a quick board thread, but really thought that discussions of Exhaust coatings and wraps merited their own thread within the Knowledge Vault Exhaust section: One of our local customers, Scott Karp, was recently in getting a Jet Hot coated header and other goodies. He works at a shop that had some thermal imaging equipment, so I asked him to perform a reasonable test to measure the header temperature differences with the stock amber SS header and the Jet Hot coated header. Here are his words about the test he ran (with some formatting and spelling corrections): "I checked for the spots that had the highest temperatures. This was consistently at the outside radius of the first bend on both pipes. I also took readings from the collector and my Drummer SS. Unfortunately the readings were done a day apart so the ambient temperature was 4 degrees different. The test drive I used was exactly the same 7.4 miles. All readings were taken within 30 seconds of reaching the shop. My findings are as follows. STOCK Header Pipe ambient temp. 67 deg. F First bend rear 492 First bend front 475 Header collector 307 Front of Muffler 92 JET HOT ambient temp. 63 deg F First bend rear 351 -->355 (corrected for ambient) First bend front 317 -->321 Header collector 285 -->289 Front of Muffler 96 --->100 I hope this will help answer questions you have had about this product. Many variables exist, but the difference is so great I'm convinced it will keep my right leg cooler on hot days." So, not a 100% controlled environment test that zero'd out ALL the other variables, but a reasonable test nonetheless. The numbers seem significant to me. FYI, this is on an XB12 with a Drummer SS and race ECM. Note the muffler temp. It is HOTTER on the Jet hot coated header. Makes me wonder if a jet hot coated header might be BAD for a glasspack muffler, as the muffler sees more heat as a result of the header not losing more heat. But on a muffler that is baffled, not packed, where muffler heat isn't a problem, seems to me that the stuff is doing what it is supposed to, by keeping the heat in the exhaust gasses to help scavenging, and keeping heat off your right leg. Al | ||
| 2k4xb12 |
Thanks Al, It would be interesting to see a similar test done on wrapped headers. | ||
| Shea |
Wow, that is a dramatic difference. I was only expecting to see a 50 degree difference, not 150. Also looking forward to seeing the wrap results too. | ||
| Blake |
What type of Jet Hot coating, the silver I assume? | ||
| Al_lighton |
Yup, silver. The temperatures were taken at the same places at about the same time offset. The engine remained running at idle while the measurements were taken. As expected, the temperatures creeped up while the bike was sitting still idling. | ||
| Ccemn1 |
Wrap destroys pipes! Now, if you've got sponsors like NASCAR, you don't have to worry about it, as they switch pipes every other race! Read this: http://www.jet-hot.com/Pages/tech1.html | ||
| Al_lighton |
Back in the other quickboard thread that spawned this thread, http://www.badweatherbikers.com/buell/messages/4062/175883.html , I wrote something that should stick with this thread. Jet hot is what we use in our header exchange program. I have them coated on my bikes, and it holds up well. I have silver. Some want black ($20 more), due to cosmetics. But I often talk people out of black. TO understand why, here's some tech talk. The Stefan-Boltzmann Law: Radiation Power ( * absporptivity ) = emissivity * Stefan's Constant * Radiation Area (Temperature of Radiator^4 - Temperature of surroundings^4) Since the temperature difference between your frame and leg and even the ambient surroundings is substantially lower than the temperature of your header, radiation heat transfer is a very significant part of the heat that is coming from your header. At slow speed, it may be the predominant mechanism, moving more heat than convection. At speed, I imagine convection is the predominant mechanism, but I haven't done the math. Assuming all else is equal, we can look to the emissivity of the surface to see what the difference is between a black header and a silver header. I cant find specific data on the Jet hot coating emmissivities, but I can make an educated guess from the table here: http://www.infrared-thermography.com/material-1.htm The emissivity of black is likely in the .90-.95 range, and the emissivity of the silver is likely in the .25-.4 range. The emissivity is a linear term in the radiation heat transfer equation, and it is 2 to 3 times higher for the black than it is for the silver. So it stands to reason that the amount of heat radiated to your leg and frame from the black header is going to be 2-3 times higher than for silver. The goal is to keep the heat in the exhaust stream for best scavenging. Since black radiates heat better, it is removing more heat from the exhaust gasses than silver. Can you measure the difference on a dyno? I dunno. But the heat transfer to my leg is the reason why I choose silver. Buell has indicated that heat to the frame may contribute to vapor lock issues as well, so anything that helps minimize the heat transfer to the frame is also good. There is conduction from the frame to my leg, so keeping the frame cooler is also a good idea for personal comfort. It would be interesting to get the same data Scott measured on his silver pipe done for black pipes. Bruce (rreater) stopped by earlier today with an IR tempearature gun from Sears...he said it was a mere $75. At that price, I'll buy one. If anyone wants to get there header coated black, I'll discount one if they promise to duplicate the test Scott did when they install their black header I'll loan the IR gun, you'd need to do the test as Scott did it and write it up similarly. Any takers? | ||
| Ccemn1 |
Al, I'm buying a D & D for my '04 XB12S from a fellow Bad Weather member & plan on Jet-Hotting it in Sterling. My question is: Do you think I should have the headers done while I'm at it? I've got a whole Arrow system done on my Aprilia Factory & love it, but I kinda like the brushed stainless look on the XB. The other side of the coin is; It should run cooler here in FL, where I frequently ride in shorts. Not so funny story for you safety conscious: I crashed in Daytona last week wearing shorts, flip flops, Icon Ti-Max jacket & Vemar helmet. I have SIX severely fractured ribs, but not a scuffed knee, or road rash anywhere from the waist down! Amazing! The bike fared very well also. I’ll need a new front left tube, bottom triple tree, front fender, left side controls (Horn, turn Sigs, Etc.) and a grip. NO alcohol, or drugs were involved either! Just a gap in my situational awareness and it really is getting nuts in Daytona! I think from now on, I’ll start going the week before. CC | ||
| Al_lighton |
The problem with the brushed stainless look is that the headers only look nice for a while before they look, well, not so nice. I polished (and repolished, and repolished) my headers on my bikes for a while, but it gets old, as it pretty much has to be done on a wheel with the headers off the bike to get the discolorations out. The jet hot loses a little bit of gloss at the hottest part near the port, otherwise, it stays nice looking. Bummer about the wreck....heal well. Cracked ribs are no laughing matter, literally. Stay away from funny things for a while. Ouch.... Al | ||
| Ccemn1 |
Thanks Al. I think I'll go that Route, as long as I've got the whole thing apart. It should improve performance & appearance all around. Here's a couple shots from that day. Almost blacked out my tattoo! CC  | ||
| Blake |
"Wrap destroys pipes!" Not in my experience and I've ridden in the rain and washed my bike plenty. Nor is that indicative of my friend LaFayette's (Buellistic's) experience. He has over 80K miles on his S3T much of that with header wrap. Stainless steel pipes with header wrap are fine. Maybe wrapping the old Cyclone plain steel headers would be problematic. I had the black jet hot coat done to my race headers. It failed to help coop the headers at all. Al's post above explains why. The silver would be the way to go. Shiny surfaces don't radiate heat well. Chrome does have its uses after all.  | ||
| Ccemn1 |
ALL after market header manufacturers void their warrantees if you use wrap. With SS you'll have better luck, but will still fatigue the metal prematurely. Ceramic is the way to go! | ||
| Buellistic |
If the header is not coated inside and out it has not been coated correctly !!! The HIGH TECH. coating of inside and out is the "BEST" way to go and is much better than the EXHAUST WRAP !!! The reason "i" do the "WRAP" is it is OLD SCHOOL and not eveyone can do it correctly ... PLUS "i" paint the wrap to seal it !!! In BUELLing LaFayette | ||
| 2k4xb12 |
LaFayette, I prefer the old school look too... Not knowing the "correct" way to do it, I did it as logically best as I could. I kept the wraps even and wrapped it in a direction that would prevent the wind from lifting the layers and allowing moisture in. Oh yeah, I sprayed it too... Check it out:  | ||
| Buellistic |
"VERY", "VERY", GOOD 2k4xb12 !!! Looks like you used SAFETY WIRE on the ends, is that correct ??? Your over laping is top notch !!! "AND" spray painting the rap is a "PLUS" !!! The aditional thing "i" did was to use saftey wire to wrap around the overlaps ... NOW WHY WOULD "i" do that, well "i" had an ARSE grab the wrap an give a twist(the aditional safety wire retards this activity) to my original job ... In BUELLing LaFayette | ||
| 2k4xb12 |
Well, I didn't use safety wire, but I did use stainless steel tye-wraps at each end (4). I've seen the stainless overwrap and I do like the way that looks, but I hadn't seen it prior to my wrapping... | ||
| Dana P. |
Al you can keep the factory stainless pipes looking awesome spending about 10 minutes.... thats right ten minutes a month if that with some Eagle One applying with paper towel and then polishing of with a soft terry cloth. And NO!!! I never had to take the header off to do it.  | ||
| Dana P. |
Chris I just had my D&D coated and it looks awesome.  | ||
| Rafartist |
What width and how much wrap did it take to finish the header and did you guys remove the header to wrap it or did you just stop it up inside the frame where you cant see it. It looks sweet. | ||
| 2k4xb12 |
Rafartist, I used the 50' x 1" wrap: http://www.eastwoodco.com/shopping/product/detailmain.jsp?itemID=3366&itemType=P RODUCT&RS=1&keyword=DEI001 along with the stainless steel locking ties: http://www.eastwoodco.com/shopping/product/detailmain.jsp?itemID=3368&itemType=P RODUCT&RS=1&keyword=DEI003 and finished it up with the high temp silicon spray: http://www.eastwoodco.com/shopping/product/detailmain.jsp?itemID=3386&itemType=P RODUCT&RS=1&keyword=DEI004 I overlapped about 50% (1/2") and the header took almost the entire 50' of wrap. I removed the header -- it's not that hard to rotate the engine... When you wrap, wrap the rear tube first, starting at the cylinder end and wrapping toward the collector, stopping where the two pipes meet, then install a stainless locking tie at each end. Next, wrap from the front cylinder end toward the collector and finish by installing a stainless tie at each end. finish by spraying the header with silicon. Expect ALOT of smoke the first couple of hours of operation after initial start-up, as well as an awful smell. | ||
| Blake |
The wrap will discolor pipes for sure, and subject the pipes to higher operational temperatures. Painting or ceramic coating the pipes is certainly a good idea and would provide additional protection against added wear and tear. | ||
| Ccemn1 |
Because of its low emissivity and insulating effect, JET-HOT Sterling creates a thermal barrier to protect headers - inside and out - while reducing heat transfer into the engine compartment. But the good news goes beyond protecting headers from thermal fatigue. Plugs, wires, fan motors, water pumps and other heat-sensitive parts get a break, too, in a cooler environment. Plus, power normally increases and safety for racers improves with lower temperatures. The company's engineering team was astounded by temperature reductions exceeding 300°F when JET-HOT Sterling was applied to standard exhaust components. Car Craft also took a cool breath, after measuring temperature reductions of over 60% on header surfaces following the application of JET-HOT. Horsepower gains depend on many variables, including engine size, type and setup; cooling system performance; ambient temperatures; and other factors. Nevertheless, JET-HOT Sterling will normally boost power when applied to headers for two reasons. First, the coating promotes denser, more potent fuel/air charges by insulating the engine bay from exhaust heat. At the same time, it accelerates the pulsed-vacuum effect on “tuned” headers, resulting in more effective scavenging of cylinders. The increased velocity of exhaust gases produced by higher exit inertia not only clears each cylinder more quickly; it also draws in the next fuel/air charge more efficiently. | ||
| Bluelightning |
Anyone ever try the blue? I have the factory blue header on my X-1 and it is scratched. It doesn't really keep the pipe any cooler than the original stock bare stainless header. I did notice that the blue header was not coated on the inside of the pipe, but want to get it recoated blue, but if it won't help out with the heat issues, I might as well leave it alone. Thoughts?? | ||
| Brineusaf |
How much does it usually cost to coat the headers...( time and money )...? | ||
| Bluelightning |
I called Jet Hot yesterday. To strip and recoat my blue header, then send back to me is $140. Turnaround time is 7-10 days. Pretty quick I think!! Best deal is you can set up and send to them directly and not have to go through a middle man, which will usually mark the prices up. | ||
| Buellistic |
Coating the INSIDE and OUTSIDE of the HEADER is the way to go !!! Once you have it done, you are done ... The WRAP will have to be redone after a time(in fact many times), "BUT" looks more "RACIE" ... | ||
| Brineusaf |
Thanks Blue - just what I was looking for, appreciate it. | ||
| Bluelightning |
Yeah, I was pretty disappointed when I got my cool Buell blue header and found it to only be coated on the exterior. I am sending mine out this week to get re-done by Jet Hot which will do the interior and exterior! | ||
| Twowheeldream |
has anyone ever wrapped a coated header? | ||
| Blake |
I have, on account of the flat black jet-Hot coating not doing much if anything to reduce the heat issue. In retrospect, it is now obvious that the super-radiating flat black finish was responsible for that more than anything. The header wrap works wonderfully. No more heat issues. | ||
| Americancycle |
i used DEI exhaust wraps on my previous bike and never had any underlying problems with the headers, the buyer also loved the look. you just gotta be sure to follow instructions from the site. http://www.deicycle.com/catalog/1/exhaust_wrap_kit s |
