Just done some online research (bored at work) - this from Century Performance in the States (having just mentioned NASCAR above). Why you should not use exhaust wrap: Header wraps are designed to keep the heat in the header to improve scavenging of the cylinders. Keeping the heat in the header allows the exhaust speed to remain high. (the right idea) Header wraps, by keeping the heat in the header, also reduces the radiant heat in the engine bay. There are no header manufacturers that I know of who will warranty their headers if header wrap has been installed on their products. This includes partial installations of the header tape on certain tubes or sections. In most cases, the header wrap damages the headers beyond repair. (I will explain below) If you run a lean mixture, you "may" see a slim performance gain using header wraps. A rich mixture may show slim to absolutely NO gain in performance. If replacing your headers and header gaskets regularly does not bother your wallet or your time, and you like that ugly look of a wrapped header, go ahead and use the heat wrap. "In the past, almost all NASCAR and other racing engine builders and crew chiefs used header wraps for the added power gains and thermal control benefits offered by their use. Problems occurred when these same teams had to replace the headers after each race (NASCAR) due to the wrap being about the only thing holding each header together. " This is more bike related: "Some years ago John Wittner (builder of Battle of the Twins Moto Guzzis) warned against the use of such wrapping on titanium pipes, which overheat, react with oxygen, and transform into a mass of loose yellow flakes. During the two-stroke era in 500cc Grand Prix, bikes appeared for the Japanese GP with pipes insulated by various means. This was done to meet new noise regulations. Later, it turned out to have undesired tuning effects so its use was discontinued." The Risks Exhaust wrapping is not without its risks. First, the higher exhaust exit temperatures can lean out the fuel mixture of an engine – sometimes severely. An overly lean situation can lead to rapid engine failure. Thus, wrapped pipes may necessitate either re-jetting or a change in mapping depending on your bike’s fuel management system. There is also a real risk of header and pipe damage due to excessive heat build-up. There are numerous reports of split and cracked exhausts that can be attributed to the use of exhaust wrap.
Yes if the headers are double skinned then it helps prevent blueing. Don't think many late Triumphs are though. The headers on my 1984 Honda SC700 are double skinned and they don't blue, but that could also be because there black chromed
It's good to talk and share, nice write up Steve, I always wanted to know the reason for it and now I know. A big thank you fella.
Big tip!! Don't let a plastic bag wrap your header pipe , looks shit and has no benefits apart from pissing off the owner!
Oh I thought it was to increase header temperatures to create a suction effect the faster the gas comes out the faster you can put fuel in
Gave you a disagree not because I think you're wrong but you can find as much stuff on tinterweb singing the praises of exhaust wraps and why you should use it This is one of those things that comes down to personal choice and is usually applied for a certain look I never wrapped any of my previous bikes but think it goes well with the twin engine in my speedmaster but would of looked shite on my Fazer
Remember seeing your speedmaster for sale when I was looking for one and before I joined this forum Only wanted one so I could wrap the exhausts but yours were already done
I used the Triumph Twin Power SAI removal kit however, these guys do a similar kit and it's cheaper... Smartmoto-electrics ....> http://stores.ebay.co.uk/SmartMoto
No worries mate . Personally I like the look of wrapping on the right bike - Bobber, Brat style, Scrambler etc. I think black would look OK on the Bonneville but imagine what a total tw*t I would look if I wrapped the Tiger!
Great thread lads. My Thruxton R is going through the Yellow to Blue phase right now. I have been looking at different brands to remove it but if (as many have mentioned) it returns quite soon after, then i might just have to live with it. Happy Days
Ahh.. All that hard work and in my case for naff all. Spent a while de blueing the Thruxton, 10 mile down the road and a while in stationary traffic and hey presto... It all came back. My Thruccy has the SAI removed and the lamba sensors too. Plus it's had a bit of work done on her by TTP (Triumph Twin Power)... Runs well, no popping on close of throttle right down to tick over, but the blueing is a thing I'll live with. Good lick though if you're still trying
A little blue looks good but the bonne (before I removed the SAI) was a horrible blue mess, yours look ok with the stainless pipes bluing in a completely different way to chrome
If I'm honest, near to the head they are a very dark blue, heading towards dark grey but I've tried to lessen the colour with a lot of effort with only a small temporary improvement. I too used Blue job, what a name for a product eh??! Bit of a mouthful if you ask me
