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Flapjack
| Posted on Sunday, September 29, 2002 - 01:49 pm: |
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Now for my 2 cents worth on the wrapped versus coated header debate. We first started wrapping headers with insulating tape in an early attemp to retain combustion heat within the pipe thus maintaining higher exhaust temperatures, increasing exhaust velocity, increasing scavenging effect in the pipe, and decreasing underhood temperature but with only partial success. Wrapped pipes do lower underhood temperatures which does lead to an increase in performance in full bodied vehicals. Wrapped headers do not retain exhaust heat in the pipe but allow it to escape and then capture it around the pipe with little or no effect on velocity or scavenging. By keeping the header surrounder by super heated air metal fatigue is accelerated leading to broken and cracked pipes and welds which I know of first hand. Corrosion and rusting are also a problem. Lastly after a couple of races the wrapping begins to look pretty tattered and with no way to clean it you are forced to rewrap the pipes if appearance counts. Coating headers with various thermal barrier products was our next step in isolating exhaust temperatures inside the pipe, increasing exhaust velocity and scavenging effect, reducing underhood temperatures while eleminating the drawbacks of wrapped headers namely metal fatigue, rust and corrosion and required maintanance. Headers coated on the ID,OD or both do contain exhaust heat in the pipe resulting in higher exhaust velocity and increased scavenging effect. Thermal barrier coated headers do reduce underhood temperatures. In March of 1991 Comp Cams ran a series of dyno test to evaluate the effectiveness of coated headers in reducing the amount of radiated(underhood) heat. A BB Chevy was used with one header uncoated and the other thermal barrier coated. Temperature probes were placed on both sides to measure exhaust gas temperature(EGT),header surface temperature(ST), and probes one inch away from the header at the bend coming out of the head, the hotest part of the header, to measure radiated temperature(RT). Dyno cell temperature was maintained at 60F thru out the test. Fourteen tests were run over a period of several hours. In preperation for the first test the engine was started and temperatures allowed to stabelize prior to the first pull. Immediately on startup RH on the uncoated header went up to 170F while the coated side remained at 60F, which was room temperature, until the first pull began. In the fourteenth test EGT was 1530F, ST 930F, RT uncoated header 200F, RT coated header only 80F one inch from the exhaust port. Because thermal barrier coated headers disepate heat much better than wrapped headers metal fatigue is not a problem. Rusting and corrosion, if the coatings are properly applied, is a thing of the past because the coatings will almost last a lifetime. when it comes time for a cleanup soap and water does the job and if the finish does dull in some spots the proper metal polish brings back the shine easily. |
Ken_Nelson
| Posted on Sunday, September 29, 2002 - 02:44 pm: |
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Is it feasible to coat only the inside of a header? Would there be any disadvantages to only coating the inside? I like the stock brushed look on the outside. How much does the coating build up, and does the decreased i.d. negatively affect performance? Thanks for the information. Ken Nelson '98 S3 |
Flapjack
| Posted on Sunday, September 29, 2002 - 03:42 pm: |
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Ken Nelson; Yes it is possible to just coat the inside of a header. I do a lot of it for the chopper guys who prefer chrome pipes but don't like the blueing that goes along with the chrome. Special ID coatings are available with a lower cure temperature so as to not affect the chrome in the curing process. On a stainless header I would use a regular ID coating with a higher cure temperature that is capable of withstanding up to 2000F. The only disadvantage to just coating the ID of the header is that OD would still require the same maintainance it does now. Come to think of it if the OD was coated it could be brushed after the polishing process was completed. Thats an option. Coating buildup on the ID of the pipe is not an issue and there would be no reduction in performance. Thanks for the interest. |
Hootowl
| Posted on Sunday, September 29, 2002 - 04:34 pm: |
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Flapjack, What's your turn-around time for a set of headers (car and bike)? |
Flapjack
| Posted on Sunday, September 29, 2002 - 05:06 pm: |
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Hootowl, I like to tell people 7 to 10 days but generally the job can be done in less time. You don't piss people off if you get it done sooner so I like to give myself a saftey factor. Thanks Jack |
Toddm2l
| Posted on Sunday, September 29, 2002 - 11:54 pm: |
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Is the 2001 and 2002 m2 the same? Want to put a new slip-on Exhaust but can't find anything. everything says 99-2001. Help, Todd |
Skulley
| Posted on Monday, September 30, 2002 - 12:42 am: |
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Flapjack, Which of your header coatings last longest. It has ben said that some of the finnishes fade with time,IE; black, chrome. Or is it just a matter of maintainance/cleaning? I am interested in Ti. |
Blake
| Posted on Monday, September 30, 2002 - 01:25 am: |
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Neil, Whoa! Check out that contact patch! Dyna, I knew that once you were able to vent, you'd return to your normal considerate self. I'm betting that if you can bubble up the issue, you will get some equitable form of resolution. Flapjack, "Wrapped headers do not retain exhaust heat in the pipe but allow it to escape and then capture it around the pipe with little or no effect on velocity or scavenging." I think what you are meaning to say is that a coating on the inside of the pipe insulates the header from direct exposure to the high temperature exhaust. I agree. It is a great system. I have a brand new race header sitting in a box that I sent to Jet Hot for a matte black coating job. As soon as I settle on a muffler for it, it will be going on the M2. As to the test results you mention... What was the thickness and type of coating used? I'm having a very hard time believing such incredible performance was achieved via the typically thin coating that we see on Jet Hot or other brands of coated Buell headers. Also, you didn't list the EGT or ST for the coated header in your last set of data. As to the effectiveness of header wraps... Insulative header wrap is VERY effective at retaining the exhaust heat within the headers. To say otherwise is simply untrue. Yes the header itself becomes very hot. As to serious corrosion... Sure if header wrap applied to plain steel (non-stainless steel) headers gets wet it will certainly exacerbate the corrosive environment. Is that really a surprise to anyone? I wrapped my '97 M2's S1W SS header for the raw "industrial" look in lieu of the stock heat shield and to keep from further melting my nylon riding pants when shifting my feet to the rear pegs. Once I get them installed, I will probably wrap the Jet Hot coated race headers too. |
Blake
| Posted on Monday, September 30, 2002 - 01:29 am: |
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Todd, Yes, 2002 M2 exhaust is the same as those on '99-'01 models. |
Jvv
| Posted on Monday, September 30, 2002 - 02:24 am: |
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Not on a Buell...but...TEXAS is close to the US of A!!!!!! ride safe....Jack |
José_Quiñones
| Posted on Monday, September 30, 2002 - 07:06 am: |
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Hey Vik What did one Erik B. tell you about Colin Edwards and the RC51 at Laguna Seca? Court, Yes the Dragon slayed the Firebolts (5 out of 8 crashed) during our BRAG weekend. Randy has not been there, yet, but will be VERY soon........ |
Bomber
| Posted on Monday, September 30, 2002 - 09:42 am: |
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Dyna . . .over the weekend, I cleared out a space in the garage . . . . bring your X1 on down, and we can save you all the labor costs . . . I've got some serious wrenching to do on the family support vehical ('31 Ford) this winter, so all the right tools will be out of the rollcab . . . . serious offer, brother . . .the jopint is heated, and stays nice and toasty with the outside temps well into the -10 range (of course, with you and me talkin in there, we'll be down to cutoffs and dago tees in no time!) besides, with yer new gig, ya need a reason to come to Illinois, yes? |
Ncbueller
| Posted on Monday, September 30, 2002 - 10:38 am: |
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Dyna: Out of curosity, what year is your X1? 99? Ride safe |
Snail
| Posted on Monday, September 30, 2002 - 10:48 am: |
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Throttle problem on my '99 S-3, yesterday's ride got a little complicated when the thrott. return ceased to function. Engine would start reving if I took my hand off the thrott. grip. Sometimes even rotating the thrott. grip back to 'off' wouldn't bring the engine back to idle, had to use the brakes to slow the engine. My feebled mind sort of kind of remembers some previous discussion about this, before I start in reading the service manual and tearning into things I thought I'd ask if anyone is famililar with this prob.? Thanks, Paul |
Ccryder
| Posted on Monday, September 30, 2002 - 10:57 am: |
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Paul: The issue was the slack in the cable would allow the cable get hung up on the bracket at the throttle body. Best way around this is keep the slack out and maybe retrofit the 2000 cable clamp bracket. On my 99' I just safety wired my cables at the TB. Take a look here: S-Wire Neil S. |
Josh
| Posted on Monday, September 30, 2002 - 10:57 am: |
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The casing for the throttle cables likes to "jump off" and get hung up at the throttle body housing as there's nothing holding it down. There a $.95 clamp on the Blast that does a good job of fixing it or Court can post his safety wire spiderweb shot again. If you keep the throttle cables properly adjusted you don't normally have the problem. I've got the Blast clamp on mine. Josh |
Snail
| Posted on Monday, September 30, 2002 - 11:38 am: |
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Thanks Josh, and Neil. Sounds like an easty fix. Paul |
Court
| Posted on Monday, September 30, 2002 - 11:55 am: |
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Quick fix..... NOTE: This is no excuse for NOT properly adjusting them as well |
Eeeeek
| Posted on Monday, September 30, 2002 - 02:08 pm: |
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Jose: Erik said Colin is a GOD to be able to win on the RC-51. Vik |
José_Quiñones
| Posted on Monday, September 30, 2002 - 03:15 pm: |
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Vik, I guess Erik B. was implying that the RC51 is a horrible race bike with that statement. Hmm.... Nicky wins the AMA Superbike Championship on, lets see, an RC51. Colin wins the World Superbike Championship on, let's see, what a coincidence, an RC51! Two American Riders on the same Japanese bike win the two top production based Championship series. If Colin is GOD, what is Nicky? If the RC51 is bad, those Ducatis, Aprilias, GSXR's, Kawasaki's and Yamahas that Colin, Nicky and HONDA beat must really suck! |
José_Quiñones
| Posted on Monday, September 30, 2002 - 03:23 pm: |
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Quote:TEXAS is close to the US of A!!!!!!
You mean like that other nearby country, New Mexico? What is Nicky? Nicky's going to GP, on what should be Colin's Ride! |
Ncbueller
| Posted on Monday, September 30, 2002 - 03:35 pm: |
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Court: If you need an additional can of safety wire, let me know. We buy it by the case. Ride Safe |
Davegess
| Posted on Monday, September 30, 2002 - 04:06 pm: |
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The RC51 was a bit of a pig at Laguna BUT Honda being Honda did new motors for the things for the second half of the season with great results. |
Dave
| Posted on Monday, September 30, 2002 - 04:46 pm: |
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Re Throttle Cables .... Adjust per factory manual specs. Safety wire 'em or use the throttle housing clamps that JOsh speaks of. Appeared on all Buells post 2000 or was it 2001? DAve |
Dynarider
| Posted on Monday, September 30, 2002 - 04:51 pm: |
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NC, its an 01. Bomber, thanks for the offer & I might just take you up on it. Gotta see what happens with the whole deal first tho. Working on it from a couple different angles at once. |
Bomber
| Posted on Monday, September 30, 2002 - 04:51 pm: |
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Dave. . . . .my 2000 M2 has the clamps |
Smokin84
| Posted on Monday, September 30, 2002 - 07:15 pm: |
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Blake, I put header wrap on my HPC coated header and it ruined the finish. You may want to ask Jet Hot if wrapping the header will harm it. Nicky is not God , but he is THE MAN. |
Fatpony
| Posted on Monday, September 30, 2002 - 07:32 pm: |
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Howdy All! I just got a D&D slip on, K&N filter setup, and race ecm. Question is can I install all and then ride it the 100 miles to the dealer for the scantilizer adj, or will it run so bad I'll ruin my wonderful ride. Thanks |
Libnosis
| Posted on Monday, September 30, 2002 - 08:07 pm: |
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Colin is damn good. But Troy won more races. I guess he's the only one that has those ducs figured out. I think he would have won had he not tried to slow Colin down for Xaus. That was one helluva race they put on last night. Congrats to the TT. lib |
Ocbueller
| Posted on Monday, September 30, 2002 - 08:11 pm: |
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Fatpony, Results may vary. Some guys have had their bikes run good before the reset and others have had theirs run extremely bad. Have an alternate form of transport to the dealer on hand just in case. SteveH |
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